Water and anomalous liquids · 2019-07-31 · Water and anomalous liquids Valentino Bianco1, Romina...
Transcript of Water and anomalous liquids · 2019-07-31 · Water and anomalous liquids Valentino Bianco1, Romina...
Water and anomalous liquids
Valentino Bianco1 Romina Ruberto2 Sergiy Ancherbak3
Giancarlo Franzese1
1Departament de Fısica Fonamental Universitat de BarcelonaDiagonal 647 08028 Barcelona Spain2 Dipartimento di Fisica Universita di Messina Italy3 Dipartimento di Fisica Universita di Pisa Italy
AbstractWater is an anomalous liquid because its properties are different from those of the
majority of liquids However the category of anomalous liquids could be greater thanwhat so far supposed Here we review what is anomalous about water which are theother liquids that are as well anomalous and which are those that could be anomalousWe ask questions such as Why water is anomalous Are the other liquids anomalousfor the same reason as water How can we define models that capture the complexityof water and other anomalous liquids but are tractable for theory and simulationsCan we make predictions with these models that can be tested in experiments Wediscuss here possible answers to these questions
Water and anomalous liquids 2
1 An overview on anomalous liquids and water
What is an anomalous liquid We define as anomalous liquid as a mono-component
substance that in the liquid phase behaves generally different in respect to the argon-
like liquids We will describe here thermodynamic anomalies dynamic anomalies
and structural anomalies that are related respectively to non-monotonic trends of
thermodynamics functions dynamics functions and structural functions upon changing
the temperature T or the pressure P of the system Among the substances showing
anomalous properties in the liquid phase we find silica (SIO2) [1ndash3] silicon (Si) [4 5]
selenium (Se) [6] phosphorus (P) [7ndash9] and water [10]
11 Thermodynamic anomalies
Water and other anomalous liquids display a maximum density in the liquid phase
related to negative thermal expansion coefficient and implying that the liquid expands
upon cooling or shrinks upon heating The presence of a temperature of maximum
density (TMD) for water is known since centuries the maximum density of water
is at sim 4 C at atmospheric pressure For this reason the thermal expansivity
αP equiv minus(1V )(partVpartT )P where V is the volume vanishes at T sim 4 C and its absolute
value increases as a power law below 4 C [11]
Other anomalous thermodynamic functions of water are the isothermal
compressibility KT equiv minus(1V )(partVpartP )T [12] and the specific heat CP equiv (partHpartT )P [13]
where H is the enthalpy of the system respectively related to fluctuations in volume
and entropy For normal liquid KT and CP tend to 0 upon cooling while in the case of
water they reach a minimum value at certain temperature (T sim 46 C for KT and T sim35 C for CP ) and than increase for decreasing T
Experiments for Ga [14] Bi [15] Te [16] S [17 18] Be Mg Ca Sr Ba [19]
SiO2 P Se Ce Cs Rb Co Ge [10] and simulations on SiO2 [20ndash22] S [5] BeF2 [20]
reveal the presence of TMD at constant pressure also for these substances in the liquid
phase As for the case of water also for these substances the TMD implies anomalies
in thermodynamic response functions
12 Dynamic anomalies
An example of dynamic anomaly is the non-monotonic behavior of diffusion constant
D as function of P In a normal liquid D decreases when density or pressure are
increased Anomalous liquids instead are characterized by a region of phase diagram
where D increases upon increasing the pressure at constant temperature In the case of
water for example experiments show that the normal behavior of D is restored only at
pressures higher than P sim11 kbar at 283 K [23]
Water and anomalous liquids 3
13 Structural anomalies and polymorphism
A typical structural anomaly is the non-monotonic behavior of structural order
parameters of the system as a function of T and P Normal liquids tend to become
more structured when compressed The molecules adopt preferential separation and a
certain orientational order This ordering can be described by two order parameters
a translational order parameter and an orientational order parameter The higher is
the value of these parameters the higher is the order of the system Therefore for
normal liquids these parameters increase with increasing pressure or density at constant
temperature Anomalous liquids instead show a region where the system becomes
more disordered as the pressure increases leading to lower values of the structural order
parameters This is emphasized in molecular dynamics simulations for water [24] and
for silica [22]
The presence of different solid structures is often related to anomalous properties of
the substance By definition a substance is polymorphic if has several crystalline phases
and is polyamorphic if has several glassy or liquid phases An example of polymorph
is water with at least 17 crystalline phases [25ndash30] some of them stable only at high
pressure Another example is carbon with graphite graphene and diamond Evidences
of polyamorphism in liquid state have been observed in phosphorous [7ndash9] triphenyl
phosphite [31ndash33] and in yttrium oxidealuminum oxide melts [34] At low temperature
and low pressure water forms low-density amorphous (LDA) ice [35] Upon increasing
the pressure it transforms from LDA to high-density amorphous (HDA) ice [25] and
upon further increasing of the pressure from HDA to very-high-density amorphous
(VHDA) [36] As we discuss later the presence of several amorphous states could
indicate the presence of a liquid-liquid phase transition
14 A few questions
Water the most common and possibly the most important liquid for life is one of the
liquids with more anomalies Despite its apparently simple structure it displays more
than sixty anomalies Water can exist as a supercooled liquid at temperatures far below
the melting temperature The lowest measured temperature for supercooled liquid water
is about -92 C at 2 kbars [37]
A characteristic feature of water molecule is the formation of hydrogen bonds (HBs)
with nearby water molecules The HBs form a dynamic network of water molecules with
a preferential tetrahedral structure At ambient pressure and temperature a few degrees
below the melting water forms a tetrahedral structure up to the second shell of each
molecule [38] Upon increasing pressure the second shell collapses on top of the first
giving rise to an increase of density of the system This experimental observation is
consistent with at least three possible scenarios suggested for supercooled water the
liquid-liquid phase transition scenario [39] the singularity-free scenario [40] and the
critical point free scenario [41] The difference among these hypothesis is related to
how the density changes from LDA to HDA These interpretations suppose that LDA
Water and anomalous liquids 4
and HDA transform with continuity in a low-density liquid (LDL) and high-density
liquid (HDL) respectively for temperatures above the temperature of spontaneous
crystallization In the case of discontinuous change in density between LDL and HDL a
first order phase transition occurs as hypothesized in the liquid-liquid phase transition
scenario In this case the phase transition could end in a liquid-liquid critical point at
positive pressure [39 42 43] at negative pressures [] or continues until the liquid-gas
limit of stability is reached at negative pressure [41] In the singularity free scenario
LDL and HDL do not represent distinct phases and the sharp but continuous change
in density is due to local density fluctuations We will discuss in the next sections these
scenarios with more details
The physics of the HBs is the key to understand the properties of water
Nevertheless there are a few natural questions that are interesting to ask
(i) Is bonding the only possible mechanism for the anomalies The interest of this
question comes from the fact that other possible mechanisms could be relevant
for explaining anomalous behavior in liquids different from water and not forming
network A simple observation is that two characteristic lengths can be associated
to water a distance at which two water molecules form hydrogen bonds and a
shorter distance of maximum approach Several potentials with two characteristic
interacting distances have been proposed to study the physics of anomalies A
recent review on this subject is Ref [44]
(ii) Can we understand if anomalies imply a liquid-liquid phase transition
(iii) A liquid-liquid phase transition would imply an anomalous behavior
(iv) How to write a microscopic theory for this phenomena
(v) Can a model be predictive and help us in designing experiments and understand
the implications for fields such as biology medicine food technology or
nanotechnology
In the following we will discuss possible answers to these questions
2 An Hamiltonian model for water
A variety of statistical models have been proposed in order to reproduce the main
features of liquid water including the anomalies From a general stand point different
models can be classified as isotropic models or as models with directional interactions
Commonly used models treat the water molecule as rigid and use isotropic interactions
due to a specific distribution of charges on the molecule The electrostatic interaction is
modeled by using Coulombrsquos law while other attractive and repulsive forces are modeled
by using the Lennard-Jones potential (eg TIP3P TIP4P and TIP5P water models)
These pair potentials reproduce water anomalies with fare agreement but do not succeed
in reproducing all the properties For example many of them fails in reproducing the
crystal phases of water However the real problem with these models is that they are
computationally expensive due to the long range Coulomb interaction
Water and anomalous liquids 5
This problem is particular relevant in simulations of biological processes where
macromolecules are surrounded by milions of water molecules To overcome this problem
a possible way is to consider coarse-grained models for water [45ndash50] In particular these
models can be used to study nano-confined water in extreme conditions and to compare
with experiments
Here we will describe in detail the model proposed by Franzese and Stanley in
2002 [46ndash51] The simplest approximation of nano-confined water is a monolayer of water
confined between two plates [52] We divide the system into cells each one occupied
by one water molecule For each cell i we associate an occupation number ni = 1 if
in the cell there is a molecule otherwise ni = 0 Each molecule has a minimum hard
core volume corresponding to the minimum volume v0 of a cell Isotropic interactions
(van der Wall attraction and hard core repulsion) in the system are represented by the
Lennard-Jones potential
U equiv minussumij
ε
[(r0
rij
)12
minus(
r0
rij
)6]
(1)
where rij is the distance between molecules i and j and the sum is performed over all
the molecules up to a cutoff distance at about three shells This term depends only
on the relative distance between two molecule and represent the isotropic part of the
interaction
In order to describe the HB interaction that is a directional interaction we
introduce variables σij = 1q [53] for each occupied site i facing the cell j The value
of q is discussed in the following Assuming that a water molecule can form up to
four HBs we fix to four the number of variables σij for each cell Variables σij are
introduced to account for the number of bonding configurations accessible to a water
molecule The state of a water molecule is completely determined by the values assumed
by the four variables σij The condition for two first neighbor molecules to form a HB is
σij = σji We adopt a geometrical definition of HB assuming that the HB is broken if
the angle H-O-O deviates more than 30 from the linear bond Therefore we consider
q = 18030 = 6 states where only 16 corresponds to the formation of a HB The
covalent HB interaction is represented by the Hamiltonian term
HHB equiv minusJsumltijgt
ninjδσijδσji
(2)
where J gt 0 represent the covalent energy gained per HB the sum is over nearest
neighbors cells and δab = 1 if a = b 0 otherwise Experimental evidences show
that the distribution of angles O-O-O is changing with T and becomes sharper and
sharper with decrease of T approaching the distribution corresponding to tetrahedral
arrangement [54] Therefore there is a correlation among HBs formed by the same
molecule Hence we introduce a term representing the many-body interaction between
the HBs of a single molecule
HCoop equiv minusJσ
sumi
sum(kl)i
δσikσil (3)
Water and anomalous liquids 6
Figure 1 Schematic representation of the model Each cell can be empty or occupatedby a water molecule with oxigen (in red) hydrogens (in blue) and lone electrons pairrepresented by gray sticks To each hydrogen and lone pair we associate a bondingvariable σij
where Jσ gt 0 is the characteristic energy of this cooperative component
The formation of a HB leads to an open structure that induces a local increase
of volume per molecule This effect is incorporated in the model by considering that
the total volume of the system depends linearly on the number of HBs So the volume
change is
V equiv V0 + NHBvHB (4)
where vHB is the increment due to the HB and V0 equiv Nv0 for N water molecules
The total enthalpy for the water is
H equiv U + HHB + HCoop + PV = U minus (J minus PvHB)NHB minus JNσ + PV0 (5)
where the total number of HB and is
NHB equivsumltijgt
ninjδσijδσji
(6)
and
Nσ equivsum
i
sum(kl)i
δσikσil (7)
is the total number of HBs optimizing the cooperative interaction [46ndash525556]
3 Phase diagram and supercooled water
By both mean field and simulations we calculate the properties of the model in Eq
(5) It reproduces qualitatively the phase diagram of water At high T it displays the
liquid-gas phase transition [46ndash525556] (Figure 2) At fixed temperature for increasing
Water and anomalous liquids 7
Figure 2 Density ρ as function of temperature T along isobars for the model in Eq(5) Labels near each isobar show the corrisponding pressure P in units of εv0 (a) Athigh temperature the discontinuity in ρ marks the liquid-gas phase transition endingin a critical point The black line represents the locus of maximum density (b) Atlow T another discontinuity in ρ marks the phase transition between HDL and LDLDashed lines approximate the coexistence regions [52]
pressure the diffusion constant increases up to a maximum reproducing the anomalous
behavior of diffusion a characteristic of water By decreasing P at constant T KT
αP and CP increase in a way that is not expected for normal liquids These anomalies
become more evident approaching the supercooled region of the phase diagram As a
rationale to this phenomena various scenarios have been proposed
The stability limit scenario [57] hypothesizes that the locus of the limit of stability
of superheated liquid water in PndashT plane have a positive slope at high T Decreasing
T this locus reaches a minimum pressure and for further decrease of T it acquires a
negative slope at low T The reentrant behavior of this locus would be consistent with
the observed anomalies of water
The liquid-liquid critical point (LLCP) scenario [39] supposes that the anomalies of
water are due to the large fluctuations of thermodynamics quantities as a consequence of
a first order phase transition in the supercooled region between two metastable liquids
at different densities the low-density liquid (LDL) at low P and low T and the high-
density liquid (HDL) at high P and high T The phase transition line ends in a critical
point and has a negative slope in the P minus T plane because the entropy is higher in the
HDL phase
Water and anomalous liquids 8
Figure 3 By mapping the system in the space of parameters J and Jσ Stokelyet al [56] recover all the scenarios proposed to explain the anomalous behavior ofsupercooled water (i) If Jσ = 0 (red line along x-axis) independently of J we recoverthe singularity-free scenario (ii) For large enough Jσ (yellow region in top left) waterexhibits a first-order liquid-liquid phase transition line terminating at the LiquidGasspinodal as predicted in the critical-point-free scenario (iii) For other combinations ofJ and Jσ water would be described by the LLCP scenario For larger Jσ the LLCP isat negative pressure (brown region between dashed lines) For smaller Jσ the LLCPis at positive pressure (orange region in bottom right)
The singularity-free scenario [53] predicts lines of maximum in the P minus T for the
response functions similar to those observed in the LLCP scenario but shows that no
singularities are present for non-zero temperatures
The critical-point-free scenario [41] hypothesizes an order-disorder transition
extending to negative pressure and reaching the supercooled limit of stability of liquid
water This scenario predicts no critical point and a behavior for the limit of stability
of liquid water as in the stability limit scenario
It is possible to map all these scenarios in the Hamiltonian model proposed by
Franzese and Stanley [Eq (5)] tuning the coupling constants J (for the covalent
component of the HBs) and Jσ (for the many-body component of the HB interaction) [56]
(Figure 3) The absence of the many-body component leads to the singularity free
scenario while a large value of the many-body component with respect to the covalent
component gives rise to the critical-point freestability limit scenario Intermediate
values of J and Jσ lead to the LLCP scenario All scenarios are obtained from the same
mechanism Estimating the parameters J and Jσ from the experiments we get Jσ sim 1
kJmol ε sim 55 kJmol and J sim 6minus 12 kJmol With this set of parameters the model
predicts the LLCP scenario with a liquid-liquid critical point C prime at positive pressure
Therefore the cooperative behavior of HBs is the principal responsible for the
anomalous behavior of water The model shows that the HB many-body component as
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
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[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
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perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 2
1 An overview on anomalous liquids and water
What is an anomalous liquid We define as anomalous liquid as a mono-component
substance that in the liquid phase behaves generally different in respect to the argon-
like liquids We will describe here thermodynamic anomalies dynamic anomalies
and structural anomalies that are related respectively to non-monotonic trends of
thermodynamics functions dynamics functions and structural functions upon changing
the temperature T or the pressure P of the system Among the substances showing
anomalous properties in the liquid phase we find silica (SIO2) [1ndash3] silicon (Si) [4 5]
selenium (Se) [6] phosphorus (P) [7ndash9] and water [10]
11 Thermodynamic anomalies
Water and other anomalous liquids display a maximum density in the liquid phase
related to negative thermal expansion coefficient and implying that the liquid expands
upon cooling or shrinks upon heating The presence of a temperature of maximum
density (TMD) for water is known since centuries the maximum density of water
is at sim 4 C at atmospheric pressure For this reason the thermal expansivity
αP equiv minus(1V )(partVpartT )P where V is the volume vanishes at T sim 4 C and its absolute
value increases as a power law below 4 C [11]
Other anomalous thermodynamic functions of water are the isothermal
compressibility KT equiv minus(1V )(partVpartP )T [12] and the specific heat CP equiv (partHpartT )P [13]
where H is the enthalpy of the system respectively related to fluctuations in volume
and entropy For normal liquid KT and CP tend to 0 upon cooling while in the case of
water they reach a minimum value at certain temperature (T sim 46 C for KT and T sim35 C for CP ) and than increase for decreasing T
Experiments for Ga [14] Bi [15] Te [16] S [17 18] Be Mg Ca Sr Ba [19]
SiO2 P Se Ce Cs Rb Co Ge [10] and simulations on SiO2 [20ndash22] S [5] BeF2 [20]
reveal the presence of TMD at constant pressure also for these substances in the liquid
phase As for the case of water also for these substances the TMD implies anomalies
in thermodynamic response functions
12 Dynamic anomalies
An example of dynamic anomaly is the non-monotonic behavior of diffusion constant
D as function of P In a normal liquid D decreases when density or pressure are
increased Anomalous liquids instead are characterized by a region of phase diagram
where D increases upon increasing the pressure at constant temperature In the case of
water for example experiments show that the normal behavior of D is restored only at
pressures higher than P sim11 kbar at 283 K [23]
Water and anomalous liquids 3
13 Structural anomalies and polymorphism
A typical structural anomaly is the non-monotonic behavior of structural order
parameters of the system as a function of T and P Normal liquids tend to become
more structured when compressed The molecules adopt preferential separation and a
certain orientational order This ordering can be described by two order parameters
a translational order parameter and an orientational order parameter The higher is
the value of these parameters the higher is the order of the system Therefore for
normal liquids these parameters increase with increasing pressure or density at constant
temperature Anomalous liquids instead show a region where the system becomes
more disordered as the pressure increases leading to lower values of the structural order
parameters This is emphasized in molecular dynamics simulations for water [24] and
for silica [22]
The presence of different solid structures is often related to anomalous properties of
the substance By definition a substance is polymorphic if has several crystalline phases
and is polyamorphic if has several glassy or liquid phases An example of polymorph
is water with at least 17 crystalline phases [25ndash30] some of them stable only at high
pressure Another example is carbon with graphite graphene and diamond Evidences
of polyamorphism in liquid state have been observed in phosphorous [7ndash9] triphenyl
phosphite [31ndash33] and in yttrium oxidealuminum oxide melts [34] At low temperature
and low pressure water forms low-density amorphous (LDA) ice [35] Upon increasing
the pressure it transforms from LDA to high-density amorphous (HDA) ice [25] and
upon further increasing of the pressure from HDA to very-high-density amorphous
(VHDA) [36] As we discuss later the presence of several amorphous states could
indicate the presence of a liquid-liquid phase transition
14 A few questions
Water the most common and possibly the most important liquid for life is one of the
liquids with more anomalies Despite its apparently simple structure it displays more
than sixty anomalies Water can exist as a supercooled liquid at temperatures far below
the melting temperature The lowest measured temperature for supercooled liquid water
is about -92 C at 2 kbars [37]
A characteristic feature of water molecule is the formation of hydrogen bonds (HBs)
with nearby water molecules The HBs form a dynamic network of water molecules with
a preferential tetrahedral structure At ambient pressure and temperature a few degrees
below the melting water forms a tetrahedral structure up to the second shell of each
molecule [38] Upon increasing pressure the second shell collapses on top of the first
giving rise to an increase of density of the system This experimental observation is
consistent with at least three possible scenarios suggested for supercooled water the
liquid-liquid phase transition scenario [39] the singularity-free scenario [40] and the
critical point free scenario [41] The difference among these hypothesis is related to
how the density changes from LDA to HDA These interpretations suppose that LDA
Water and anomalous liquids 4
and HDA transform with continuity in a low-density liquid (LDL) and high-density
liquid (HDL) respectively for temperatures above the temperature of spontaneous
crystallization In the case of discontinuous change in density between LDL and HDL a
first order phase transition occurs as hypothesized in the liquid-liquid phase transition
scenario In this case the phase transition could end in a liquid-liquid critical point at
positive pressure [39 42 43] at negative pressures [] or continues until the liquid-gas
limit of stability is reached at negative pressure [41] In the singularity free scenario
LDL and HDL do not represent distinct phases and the sharp but continuous change
in density is due to local density fluctuations We will discuss in the next sections these
scenarios with more details
The physics of the HBs is the key to understand the properties of water
Nevertheless there are a few natural questions that are interesting to ask
(i) Is bonding the only possible mechanism for the anomalies The interest of this
question comes from the fact that other possible mechanisms could be relevant
for explaining anomalous behavior in liquids different from water and not forming
network A simple observation is that two characteristic lengths can be associated
to water a distance at which two water molecules form hydrogen bonds and a
shorter distance of maximum approach Several potentials with two characteristic
interacting distances have been proposed to study the physics of anomalies A
recent review on this subject is Ref [44]
(ii) Can we understand if anomalies imply a liquid-liquid phase transition
(iii) A liquid-liquid phase transition would imply an anomalous behavior
(iv) How to write a microscopic theory for this phenomena
(v) Can a model be predictive and help us in designing experiments and understand
the implications for fields such as biology medicine food technology or
nanotechnology
In the following we will discuss possible answers to these questions
2 An Hamiltonian model for water
A variety of statistical models have been proposed in order to reproduce the main
features of liquid water including the anomalies From a general stand point different
models can be classified as isotropic models or as models with directional interactions
Commonly used models treat the water molecule as rigid and use isotropic interactions
due to a specific distribution of charges on the molecule The electrostatic interaction is
modeled by using Coulombrsquos law while other attractive and repulsive forces are modeled
by using the Lennard-Jones potential (eg TIP3P TIP4P and TIP5P water models)
These pair potentials reproduce water anomalies with fare agreement but do not succeed
in reproducing all the properties For example many of them fails in reproducing the
crystal phases of water However the real problem with these models is that they are
computationally expensive due to the long range Coulomb interaction
Water and anomalous liquids 5
This problem is particular relevant in simulations of biological processes where
macromolecules are surrounded by milions of water molecules To overcome this problem
a possible way is to consider coarse-grained models for water [45ndash50] In particular these
models can be used to study nano-confined water in extreme conditions and to compare
with experiments
Here we will describe in detail the model proposed by Franzese and Stanley in
2002 [46ndash51] The simplest approximation of nano-confined water is a monolayer of water
confined between two plates [52] We divide the system into cells each one occupied
by one water molecule For each cell i we associate an occupation number ni = 1 if
in the cell there is a molecule otherwise ni = 0 Each molecule has a minimum hard
core volume corresponding to the minimum volume v0 of a cell Isotropic interactions
(van der Wall attraction and hard core repulsion) in the system are represented by the
Lennard-Jones potential
U equiv minussumij
ε
[(r0
rij
)12
minus(
r0
rij
)6]
(1)
where rij is the distance between molecules i and j and the sum is performed over all
the molecules up to a cutoff distance at about three shells This term depends only
on the relative distance between two molecule and represent the isotropic part of the
interaction
In order to describe the HB interaction that is a directional interaction we
introduce variables σij = 1q [53] for each occupied site i facing the cell j The value
of q is discussed in the following Assuming that a water molecule can form up to
four HBs we fix to four the number of variables σij for each cell Variables σij are
introduced to account for the number of bonding configurations accessible to a water
molecule The state of a water molecule is completely determined by the values assumed
by the four variables σij The condition for two first neighbor molecules to form a HB is
σij = σji We adopt a geometrical definition of HB assuming that the HB is broken if
the angle H-O-O deviates more than 30 from the linear bond Therefore we consider
q = 18030 = 6 states where only 16 corresponds to the formation of a HB The
covalent HB interaction is represented by the Hamiltonian term
HHB equiv minusJsumltijgt
ninjδσijδσji
(2)
where J gt 0 represent the covalent energy gained per HB the sum is over nearest
neighbors cells and δab = 1 if a = b 0 otherwise Experimental evidences show
that the distribution of angles O-O-O is changing with T and becomes sharper and
sharper with decrease of T approaching the distribution corresponding to tetrahedral
arrangement [54] Therefore there is a correlation among HBs formed by the same
molecule Hence we introduce a term representing the many-body interaction between
the HBs of a single molecule
HCoop equiv minusJσ
sumi
sum(kl)i
δσikσil (3)
Water and anomalous liquids 6
Figure 1 Schematic representation of the model Each cell can be empty or occupatedby a water molecule with oxigen (in red) hydrogens (in blue) and lone electrons pairrepresented by gray sticks To each hydrogen and lone pair we associate a bondingvariable σij
where Jσ gt 0 is the characteristic energy of this cooperative component
The formation of a HB leads to an open structure that induces a local increase
of volume per molecule This effect is incorporated in the model by considering that
the total volume of the system depends linearly on the number of HBs So the volume
change is
V equiv V0 + NHBvHB (4)
where vHB is the increment due to the HB and V0 equiv Nv0 for N water molecules
The total enthalpy for the water is
H equiv U + HHB + HCoop + PV = U minus (J minus PvHB)NHB minus JNσ + PV0 (5)
where the total number of HB and is
NHB equivsumltijgt
ninjδσijδσji
(6)
and
Nσ equivsum
i
sum(kl)i
δσikσil (7)
is the total number of HBs optimizing the cooperative interaction [46ndash525556]
3 Phase diagram and supercooled water
By both mean field and simulations we calculate the properties of the model in Eq
(5) It reproduces qualitatively the phase diagram of water At high T it displays the
liquid-gas phase transition [46ndash525556] (Figure 2) At fixed temperature for increasing
Water and anomalous liquids 7
Figure 2 Density ρ as function of temperature T along isobars for the model in Eq(5) Labels near each isobar show the corrisponding pressure P in units of εv0 (a) Athigh temperature the discontinuity in ρ marks the liquid-gas phase transition endingin a critical point The black line represents the locus of maximum density (b) Atlow T another discontinuity in ρ marks the phase transition between HDL and LDLDashed lines approximate the coexistence regions [52]
pressure the diffusion constant increases up to a maximum reproducing the anomalous
behavior of diffusion a characteristic of water By decreasing P at constant T KT
αP and CP increase in a way that is not expected for normal liquids These anomalies
become more evident approaching the supercooled region of the phase diagram As a
rationale to this phenomena various scenarios have been proposed
The stability limit scenario [57] hypothesizes that the locus of the limit of stability
of superheated liquid water in PndashT plane have a positive slope at high T Decreasing
T this locus reaches a minimum pressure and for further decrease of T it acquires a
negative slope at low T The reentrant behavior of this locus would be consistent with
the observed anomalies of water
The liquid-liquid critical point (LLCP) scenario [39] supposes that the anomalies of
water are due to the large fluctuations of thermodynamics quantities as a consequence of
a first order phase transition in the supercooled region between two metastable liquids
at different densities the low-density liquid (LDL) at low P and low T and the high-
density liquid (HDL) at high P and high T The phase transition line ends in a critical
point and has a negative slope in the P minus T plane because the entropy is higher in the
HDL phase
Water and anomalous liquids 8
Figure 3 By mapping the system in the space of parameters J and Jσ Stokelyet al [56] recover all the scenarios proposed to explain the anomalous behavior ofsupercooled water (i) If Jσ = 0 (red line along x-axis) independently of J we recoverthe singularity-free scenario (ii) For large enough Jσ (yellow region in top left) waterexhibits a first-order liquid-liquid phase transition line terminating at the LiquidGasspinodal as predicted in the critical-point-free scenario (iii) For other combinations ofJ and Jσ water would be described by the LLCP scenario For larger Jσ the LLCP isat negative pressure (brown region between dashed lines) For smaller Jσ the LLCPis at positive pressure (orange region in bottom right)
The singularity-free scenario [53] predicts lines of maximum in the P minus T for the
response functions similar to those observed in the LLCP scenario but shows that no
singularities are present for non-zero temperatures
The critical-point-free scenario [41] hypothesizes an order-disorder transition
extending to negative pressure and reaching the supercooled limit of stability of liquid
water This scenario predicts no critical point and a behavior for the limit of stability
of liquid water as in the stability limit scenario
It is possible to map all these scenarios in the Hamiltonian model proposed by
Franzese and Stanley [Eq (5)] tuning the coupling constants J (for the covalent
component of the HBs) and Jσ (for the many-body component of the HB interaction) [56]
(Figure 3) The absence of the many-body component leads to the singularity free
scenario while a large value of the many-body component with respect to the covalent
component gives rise to the critical-point freestability limit scenario Intermediate
values of J and Jσ lead to the LLCP scenario All scenarios are obtained from the same
mechanism Estimating the parameters J and Jσ from the experiments we get Jσ sim 1
kJmol ε sim 55 kJmol and J sim 6minus 12 kJmol With this set of parameters the model
predicts the LLCP scenario with a liquid-liquid critical point C prime at positive pressure
Therefore the cooperative behavior of HBs is the principal responsible for the
anomalous behavior of water The model shows that the HB many-body component as
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 3
13 Structural anomalies and polymorphism
A typical structural anomaly is the non-monotonic behavior of structural order
parameters of the system as a function of T and P Normal liquids tend to become
more structured when compressed The molecules adopt preferential separation and a
certain orientational order This ordering can be described by two order parameters
a translational order parameter and an orientational order parameter The higher is
the value of these parameters the higher is the order of the system Therefore for
normal liquids these parameters increase with increasing pressure or density at constant
temperature Anomalous liquids instead show a region where the system becomes
more disordered as the pressure increases leading to lower values of the structural order
parameters This is emphasized in molecular dynamics simulations for water [24] and
for silica [22]
The presence of different solid structures is often related to anomalous properties of
the substance By definition a substance is polymorphic if has several crystalline phases
and is polyamorphic if has several glassy or liquid phases An example of polymorph
is water with at least 17 crystalline phases [25ndash30] some of them stable only at high
pressure Another example is carbon with graphite graphene and diamond Evidences
of polyamorphism in liquid state have been observed in phosphorous [7ndash9] triphenyl
phosphite [31ndash33] and in yttrium oxidealuminum oxide melts [34] At low temperature
and low pressure water forms low-density amorphous (LDA) ice [35] Upon increasing
the pressure it transforms from LDA to high-density amorphous (HDA) ice [25] and
upon further increasing of the pressure from HDA to very-high-density amorphous
(VHDA) [36] As we discuss later the presence of several amorphous states could
indicate the presence of a liquid-liquid phase transition
14 A few questions
Water the most common and possibly the most important liquid for life is one of the
liquids with more anomalies Despite its apparently simple structure it displays more
than sixty anomalies Water can exist as a supercooled liquid at temperatures far below
the melting temperature The lowest measured temperature for supercooled liquid water
is about -92 C at 2 kbars [37]
A characteristic feature of water molecule is the formation of hydrogen bonds (HBs)
with nearby water molecules The HBs form a dynamic network of water molecules with
a preferential tetrahedral structure At ambient pressure and temperature a few degrees
below the melting water forms a tetrahedral structure up to the second shell of each
molecule [38] Upon increasing pressure the second shell collapses on top of the first
giving rise to an increase of density of the system This experimental observation is
consistent with at least three possible scenarios suggested for supercooled water the
liquid-liquid phase transition scenario [39] the singularity-free scenario [40] and the
critical point free scenario [41] The difference among these hypothesis is related to
how the density changes from LDA to HDA These interpretations suppose that LDA
Water and anomalous liquids 4
and HDA transform with continuity in a low-density liquid (LDL) and high-density
liquid (HDL) respectively for temperatures above the temperature of spontaneous
crystallization In the case of discontinuous change in density between LDL and HDL a
first order phase transition occurs as hypothesized in the liquid-liquid phase transition
scenario In this case the phase transition could end in a liquid-liquid critical point at
positive pressure [39 42 43] at negative pressures [] or continues until the liquid-gas
limit of stability is reached at negative pressure [41] In the singularity free scenario
LDL and HDL do not represent distinct phases and the sharp but continuous change
in density is due to local density fluctuations We will discuss in the next sections these
scenarios with more details
The physics of the HBs is the key to understand the properties of water
Nevertheless there are a few natural questions that are interesting to ask
(i) Is bonding the only possible mechanism for the anomalies The interest of this
question comes from the fact that other possible mechanisms could be relevant
for explaining anomalous behavior in liquids different from water and not forming
network A simple observation is that two characteristic lengths can be associated
to water a distance at which two water molecules form hydrogen bonds and a
shorter distance of maximum approach Several potentials with two characteristic
interacting distances have been proposed to study the physics of anomalies A
recent review on this subject is Ref [44]
(ii) Can we understand if anomalies imply a liquid-liquid phase transition
(iii) A liquid-liquid phase transition would imply an anomalous behavior
(iv) How to write a microscopic theory for this phenomena
(v) Can a model be predictive and help us in designing experiments and understand
the implications for fields such as biology medicine food technology or
nanotechnology
In the following we will discuss possible answers to these questions
2 An Hamiltonian model for water
A variety of statistical models have been proposed in order to reproduce the main
features of liquid water including the anomalies From a general stand point different
models can be classified as isotropic models or as models with directional interactions
Commonly used models treat the water molecule as rigid and use isotropic interactions
due to a specific distribution of charges on the molecule The electrostatic interaction is
modeled by using Coulombrsquos law while other attractive and repulsive forces are modeled
by using the Lennard-Jones potential (eg TIP3P TIP4P and TIP5P water models)
These pair potentials reproduce water anomalies with fare agreement but do not succeed
in reproducing all the properties For example many of them fails in reproducing the
crystal phases of water However the real problem with these models is that they are
computationally expensive due to the long range Coulomb interaction
Water and anomalous liquids 5
This problem is particular relevant in simulations of biological processes where
macromolecules are surrounded by milions of water molecules To overcome this problem
a possible way is to consider coarse-grained models for water [45ndash50] In particular these
models can be used to study nano-confined water in extreme conditions and to compare
with experiments
Here we will describe in detail the model proposed by Franzese and Stanley in
2002 [46ndash51] The simplest approximation of nano-confined water is a monolayer of water
confined between two plates [52] We divide the system into cells each one occupied
by one water molecule For each cell i we associate an occupation number ni = 1 if
in the cell there is a molecule otherwise ni = 0 Each molecule has a minimum hard
core volume corresponding to the minimum volume v0 of a cell Isotropic interactions
(van der Wall attraction and hard core repulsion) in the system are represented by the
Lennard-Jones potential
U equiv minussumij
ε
[(r0
rij
)12
minus(
r0
rij
)6]
(1)
where rij is the distance between molecules i and j and the sum is performed over all
the molecules up to a cutoff distance at about three shells This term depends only
on the relative distance between two molecule and represent the isotropic part of the
interaction
In order to describe the HB interaction that is a directional interaction we
introduce variables σij = 1q [53] for each occupied site i facing the cell j The value
of q is discussed in the following Assuming that a water molecule can form up to
four HBs we fix to four the number of variables σij for each cell Variables σij are
introduced to account for the number of bonding configurations accessible to a water
molecule The state of a water molecule is completely determined by the values assumed
by the four variables σij The condition for two first neighbor molecules to form a HB is
σij = σji We adopt a geometrical definition of HB assuming that the HB is broken if
the angle H-O-O deviates more than 30 from the linear bond Therefore we consider
q = 18030 = 6 states where only 16 corresponds to the formation of a HB The
covalent HB interaction is represented by the Hamiltonian term
HHB equiv minusJsumltijgt
ninjδσijδσji
(2)
where J gt 0 represent the covalent energy gained per HB the sum is over nearest
neighbors cells and δab = 1 if a = b 0 otherwise Experimental evidences show
that the distribution of angles O-O-O is changing with T and becomes sharper and
sharper with decrease of T approaching the distribution corresponding to tetrahedral
arrangement [54] Therefore there is a correlation among HBs formed by the same
molecule Hence we introduce a term representing the many-body interaction between
the HBs of a single molecule
HCoop equiv minusJσ
sumi
sum(kl)i
δσikσil (3)
Water and anomalous liquids 6
Figure 1 Schematic representation of the model Each cell can be empty or occupatedby a water molecule with oxigen (in red) hydrogens (in blue) and lone electrons pairrepresented by gray sticks To each hydrogen and lone pair we associate a bondingvariable σij
where Jσ gt 0 is the characteristic energy of this cooperative component
The formation of a HB leads to an open structure that induces a local increase
of volume per molecule This effect is incorporated in the model by considering that
the total volume of the system depends linearly on the number of HBs So the volume
change is
V equiv V0 + NHBvHB (4)
where vHB is the increment due to the HB and V0 equiv Nv0 for N water molecules
The total enthalpy for the water is
H equiv U + HHB + HCoop + PV = U minus (J minus PvHB)NHB minus JNσ + PV0 (5)
where the total number of HB and is
NHB equivsumltijgt
ninjδσijδσji
(6)
and
Nσ equivsum
i
sum(kl)i
δσikσil (7)
is the total number of HBs optimizing the cooperative interaction [46ndash525556]
3 Phase diagram and supercooled water
By both mean field and simulations we calculate the properties of the model in Eq
(5) It reproduces qualitatively the phase diagram of water At high T it displays the
liquid-gas phase transition [46ndash525556] (Figure 2) At fixed temperature for increasing
Water and anomalous liquids 7
Figure 2 Density ρ as function of temperature T along isobars for the model in Eq(5) Labels near each isobar show the corrisponding pressure P in units of εv0 (a) Athigh temperature the discontinuity in ρ marks the liquid-gas phase transition endingin a critical point The black line represents the locus of maximum density (b) Atlow T another discontinuity in ρ marks the phase transition between HDL and LDLDashed lines approximate the coexistence regions [52]
pressure the diffusion constant increases up to a maximum reproducing the anomalous
behavior of diffusion a characteristic of water By decreasing P at constant T KT
αP and CP increase in a way that is not expected for normal liquids These anomalies
become more evident approaching the supercooled region of the phase diagram As a
rationale to this phenomena various scenarios have been proposed
The stability limit scenario [57] hypothesizes that the locus of the limit of stability
of superheated liquid water in PndashT plane have a positive slope at high T Decreasing
T this locus reaches a minimum pressure and for further decrease of T it acquires a
negative slope at low T The reentrant behavior of this locus would be consistent with
the observed anomalies of water
The liquid-liquid critical point (LLCP) scenario [39] supposes that the anomalies of
water are due to the large fluctuations of thermodynamics quantities as a consequence of
a first order phase transition in the supercooled region between two metastable liquids
at different densities the low-density liquid (LDL) at low P and low T and the high-
density liquid (HDL) at high P and high T The phase transition line ends in a critical
point and has a negative slope in the P minus T plane because the entropy is higher in the
HDL phase
Water and anomalous liquids 8
Figure 3 By mapping the system in the space of parameters J and Jσ Stokelyet al [56] recover all the scenarios proposed to explain the anomalous behavior ofsupercooled water (i) If Jσ = 0 (red line along x-axis) independently of J we recoverthe singularity-free scenario (ii) For large enough Jσ (yellow region in top left) waterexhibits a first-order liquid-liquid phase transition line terminating at the LiquidGasspinodal as predicted in the critical-point-free scenario (iii) For other combinations ofJ and Jσ water would be described by the LLCP scenario For larger Jσ the LLCP isat negative pressure (brown region between dashed lines) For smaller Jσ the LLCPis at positive pressure (orange region in bottom right)
The singularity-free scenario [53] predicts lines of maximum in the P minus T for the
response functions similar to those observed in the LLCP scenario but shows that no
singularities are present for non-zero temperatures
The critical-point-free scenario [41] hypothesizes an order-disorder transition
extending to negative pressure and reaching the supercooled limit of stability of liquid
water This scenario predicts no critical point and a behavior for the limit of stability
of liquid water as in the stability limit scenario
It is possible to map all these scenarios in the Hamiltonian model proposed by
Franzese and Stanley [Eq (5)] tuning the coupling constants J (for the covalent
component of the HBs) and Jσ (for the many-body component of the HB interaction) [56]
(Figure 3) The absence of the many-body component leads to the singularity free
scenario while a large value of the many-body component with respect to the covalent
component gives rise to the critical-point freestability limit scenario Intermediate
values of J and Jσ lead to the LLCP scenario All scenarios are obtained from the same
mechanism Estimating the parameters J and Jσ from the experiments we get Jσ sim 1
kJmol ε sim 55 kJmol and J sim 6minus 12 kJmol With this set of parameters the model
predicts the LLCP scenario with a liquid-liquid critical point C prime at positive pressure
Therefore the cooperative behavior of HBs is the principal responsible for the
anomalous behavior of water The model shows that the HB many-body component as
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 4
and HDA transform with continuity in a low-density liquid (LDL) and high-density
liquid (HDL) respectively for temperatures above the temperature of spontaneous
crystallization In the case of discontinuous change in density between LDL and HDL a
first order phase transition occurs as hypothesized in the liquid-liquid phase transition
scenario In this case the phase transition could end in a liquid-liquid critical point at
positive pressure [39 42 43] at negative pressures [] or continues until the liquid-gas
limit of stability is reached at negative pressure [41] In the singularity free scenario
LDL and HDL do not represent distinct phases and the sharp but continuous change
in density is due to local density fluctuations We will discuss in the next sections these
scenarios with more details
The physics of the HBs is the key to understand the properties of water
Nevertheless there are a few natural questions that are interesting to ask
(i) Is bonding the only possible mechanism for the anomalies The interest of this
question comes from the fact that other possible mechanisms could be relevant
for explaining anomalous behavior in liquids different from water and not forming
network A simple observation is that two characteristic lengths can be associated
to water a distance at which two water molecules form hydrogen bonds and a
shorter distance of maximum approach Several potentials with two characteristic
interacting distances have been proposed to study the physics of anomalies A
recent review on this subject is Ref [44]
(ii) Can we understand if anomalies imply a liquid-liquid phase transition
(iii) A liquid-liquid phase transition would imply an anomalous behavior
(iv) How to write a microscopic theory for this phenomena
(v) Can a model be predictive and help us in designing experiments and understand
the implications for fields such as biology medicine food technology or
nanotechnology
In the following we will discuss possible answers to these questions
2 An Hamiltonian model for water
A variety of statistical models have been proposed in order to reproduce the main
features of liquid water including the anomalies From a general stand point different
models can be classified as isotropic models or as models with directional interactions
Commonly used models treat the water molecule as rigid and use isotropic interactions
due to a specific distribution of charges on the molecule The electrostatic interaction is
modeled by using Coulombrsquos law while other attractive and repulsive forces are modeled
by using the Lennard-Jones potential (eg TIP3P TIP4P and TIP5P water models)
These pair potentials reproduce water anomalies with fare agreement but do not succeed
in reproducing all the properties For example many of them fails in reproducing the
crystal phases of water However the real problem with these models is that they are
computationally expensive due to the long range Coulomb interaction
Water and anomalous liquids 5
This problem is particular relevant in simulations of biological processes where
macromolecules are surrounded by milions of water molecules To overcome this problem
a possible way is to consider coarse-grained models for water [45ndash50] In particular these
models can be used to study nano-confined water in extreme conditions and to compare
with experiments
Here we will describe in detail the model proposed by Franzese and Stanley in
2002 [46ndash51] The simplest approximation of nano-confined water is a monolayer of water
confined between two plates [52] We divide the system into cells each one occupied
by one water molecule For each cell i we associate an occupation number ni = 1 if
in the cell there is a molecule otherwise ni = 0 Each molecule has a minimum hard
core volume corresponding to the minimum volume v0 of a cell Isotropic interactions
(van der Wall attraction and hard core repulsion) in the system are represented by the
Lennard-Jones potential
U equiv minussumij
ε
[(r0
rij
)12
minus(
r0
rij
)6]
(1)
where rij is the distance between molecules i and j and the sum is performed over all
the molecules up to a cutoff distance at about three shells This term depends only
on the relative distance between two molecule and represent the isotropic part of the
interaction
In order to describe the HB interaction that is a directional interaction we
introduce variables σij = 1q [53] for each occupied site i facing the cell j The value
of q is discussed in the following Assuming that a water molecule can form up to
four HBs we fix to four the number of variables σij for each cell Variables σij are
introduced to account for the number of bonding configurations accessible to a water
molecule The state of a water molecule is completely determined by the values assumed
by the four variables σij The condition for two first neighbor molecules to form a HB is
σij = σji We adopt a geometrical definition of HB assuming that the HB is broken if
the angle H-O-O deviates more than 30 from the linear bond Therefore we consider
q = 18030 = 6 states where only 16 corresponds to the formation of a HB The
covalent HB interaction is represented by the Hamiltonian term
HHB equiv minusJsumltijgt
ninjδσijδσji
(2)
where J gt 0 represent the covalent energy gained per HB the sum is over nearest
neighbors cells and δab = 1 if a = b 0 otherwise Experimental evidences show
that the distribution of angles O-O-O is changing with T and becomes sharper and
sharper with decrease of T approaching the distribution corresponding to tetrahedral
arrangement [54] Therefore there is a correlation among HBs formed by the same
molecule Hence we introduce a term representing the many-body interaction between
the HBs of a single molecule
HCoop equiv minusJσ
sumi
sum(kl)i
δσikσil (3)
Water and anomalous liquids 6
Figure 1 Schematic representation of the model Each cell can be empty or occupatedby a water molecule with oxigen (in red) hydrogens (in blue) and lone electrons pairrepresented by gray sticks To each hydrogen and lone pair we associate a bondingvariable σij
where Jσ gt 0 is the characteristic energy of this cooperative component
The formation of a HB leads to an open structure that induces a local increase
of volume per molecule This effect is incorporated in the model by considering that
the total volume of the system depends linearly on the number of HBs So the volume
change is
V equiv V0 + NHBvHB (4)
where vHB is the increment due to the HB and V0 equiv Nv0 for N water molecules
The total enthalpy for the water is
H equiv U + HHB + HCoop + PV = U minus (J minus PvHB)NHB minus JNσ + PV0 (5)
where the total number of HB and is
NHB equivsumltijgt
ninjδσijδσji
(6)
and
Nσ equivsum
i
sum(kl)i
δσikσil (7)
is the total number of HBs optimizing the cooperative interaction [46ndash525556]
3 Phase diagram and supercooled water
By both mean field and simulations we calculate the properties of the model in Eq
(5) It reproduces qualitatively the phase diagram of water At high T it displays the
liquid-gas phase transition [46ndash525556] (Figure 2) At fixed temperature for increasing
Water and anomalous liquids 7
Figure 2 Density ρ as function of temperature T along isobars for the model in Eq(5) Labels near each isobar show the corrisponding pressure P in units of εv0 (a) Athigh temperature the discontinuity in ρ marks the liquid-gas phase transition endingin a critical point The black line represents the locus of maximum density (b) Atlow T another discontinuity in ρ marks the phase transition between HDL and LDLDashed lines approximate the coexistence regions [52]
pressure the diffusion constant increases up to a maximum reproducing the anomalous
behavior of diffusion a characteristic of water By decreasing P at constant T KT
αP and CP increase in a way that is not expected for normal liquids These anomalies
become more evident approaching the supercooled region of the phase diagram As a
rationale to this phenomena various scenarios have been proposed
The stability limit scenario [57] hypothesizes that the locus of the limit of stability
of superheated liquid water in PndashT plane have a positive slope at high T Decreasing
T this locus reaches a minimum pressure and for further decrease of T it acquires a
negative slope at low T The reentrant behavior of this locus would be consistent with
the observed anomalies of water
The liquid-liquid critical point (LLCP) scenario [39] supposes that the anomalies of
water are due to the large fluctuations of thermodynamics quantities as a consequence of
a first order phase transition in the supercooled region between two metastable liquids
at different densities the low-density liquid (LDL) at low P and low T and the high-
density liquid (HDL) at high P and high T The phase transition line ends in a critical
point and has a negative slope in the P minus T plane because the entropy is higher in the
HDL phase
Water and anomalous liquids 8
Figure 3 By mapping the system in the space of parameters J and Jσ Stokelyet al [56] recover all the scenarios proposed to explain the anomalous behavior ofsupercooled water (i) If Jσ = 0 (red line along x-axis) independently of J we recoverthe singularity-free scenario (ii) For large enough Jσ (yellow region in top left) waterexhibits a first-order liquid-liquid phase transition line terminating at the LiquidGasspinodal as predicted in the critical-point-free scenario (iii) For other combinations ofJ and Jσ water would be described by the LLCP scenario For larger Jσ the LLCP isat negative pressure (brown region between dashed lines) For smaller Jσ the LLCPis at positive pressure (orange region in bottom right)
The singularity-free scenario [53] predicts lines of maximum in the P minus T for the
response functions similar to those observed in the LLCP scenario but shows that no
singularities are present for non-zero temperatures
The critical-point-free scenario [41] hypothesizes an order-disorder transition
extending to negative pressure and reaching the supercooled limit of stability of liquid
water This scenario predicts no critical point and a behavior for the limit of stability
of liquid water as in the stability limit scenario
It is possible to map all these scenarios in the Hamiltonian model proposed by
Franzese and Stanley [Eq (5)] tuning the coupling constants J (for the covalent
component of the HBs) and Jσ (for the many-body component of the HB interaction) [56]
(Figure 3) The absence of the many-body component leads to the singularity free
scenario while a large value of the many-body component with respect to the covalent
component gives rise to the critical-point freestability limit scenario Intermediate
values of J and Jσ lead to the LLCP scenario All scenarios are obtained from the same
mechanism Estimating the parameters J and Jσ from the experiments we get Jσ sim 1
kJmol ε sim 55 kJmol and J sim 6minus 12 kJmol With this set of parameters the model
predicts the LLCP scenario with a liquid-liquid critical point C prime at positive pressure
Therefore the cooperative behavior of HBs is the principal responsible for the
anomalous behavior of water The model shows that the HB many-body component as
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 5
This problem is particular relevant in simulations of biological processes where
macromolecules are surrounded by milions of water molecules To overcome this problem
a possible way is to consider coarse-grained models for water [45ndash50] In particular these
models can be used to study nano-confined water in extreme conditions and to compare
with experiments
Here we will describe in detail the model proposed by Franzese and Stanley in
2002 [46ndash51] The simplest approximation of nano-confined water is a monolayer of water
confined between two plates [52] We divide the system into cells each one occupied
by one water molecule For each cell i we associate an occupation number ni = 1 if
in the cell there is a molecule otherwise ni = 0 Each molecule has a minimum hard
core volume corresponding to the minimum volume v0 of a cell Isotropic interactions
(van der Wall attraction and hard core repulsion) in the system are represented by the
Lennard-Jones potential
U equiv minussumij
ε
[(r0
rij
)12
minus(
r0
rij
)6]
(1)
where rij is the distance between molecules i and j and the sum is performed over all
the molecules up to a cutoff distance at about three shells This term depends only
on the relative distance between two molecule and represent the isotropic part of the
interaction
In order to describe the HB interaction that is a directional interaction we
introduce variables σij = 1q [53] for each occupied site i facing the cell j The value
of q is discussed in the following Assuming that a water molecule can form up to
four HBs we fix to four the number of variables σij for each cell Variables σij are
introduced to account for the number of bonding configurations accessible to a water
molecule The state of a water molecule is completely determined by the values assumed
by the four variables σij The condition for two first neighbor molecules to form a HB is
σij = σji We adopt a geometrical definition of HB assuming that the HB is broken if
the angle H-O-O deviates more than 30 from the linear bond Therefore we consider
q = 18030 = 6 states where only 16 corresponds to the formation of a HB The
covalent HB interaction is represented by the Hamiltonian term
HHB equiv minusJsumltijgt
ninjδσijδσji
(2)
where J gt 0 represent the covalent energy gained per HB the sum is over nearest
neighbors cells and δab = 1 if a = b 0 otherwise Experimental evidences show
that the distribution of angles O-O-O is changing with T and becomes sharper and
sharper with decrease of T approaching the distribution corresponding to tetrahedral
arrangement [54] Therefore there is a correlation among HBs formed by the same
molecule Hence we introduce a term representing the many-body interaction between
the HBs of a single molecule
HCoop equiv minusJσ
sumi
sum(kl)i
δσikσil (3)
Water and anomalous liquids 6
Figure 1 Schematic representation of the model Each cell can be empty or occupatedby a water molecule with oxigen (in red) hydrogens (in blue) and lone electrons pairrepresented by gray sticks To each hydrogen and lone pair we associate a bondingvariable σij
where Jσ gt 0 is the characteristic energy of this cooperative component
The formation of a HB leads to an open structure that induces a local increase
of volume per molecule This effect is incorporated in the model by considering that
the total volume of the system depends linearly on the number of HBs So the volume
change is
V equiv V0 + NHBvHB (4)
where vHB is the increment due to the HB and V0 equiv Nv0 for N water molecules
The total enthalpy for the water is
H equiv U + HHB + HCoop + PV = U minus (J minus PvHB)NHB minus JNσ + PV0 (5)
where the total number of HB and is
NHB equivsumltijgt
ninjδσijδσji
(6)
and
Nσ equivsum
i
sum(kl)i
δσikσil (7)
is the total number of HBs optimizing the cooperative interaction [46ndash525556]
3 Phase diagram and supercooled water
By both mean field and simulations we calculate the properties of the model in Eq
(5) It reproduces qualitatively the phase diagram of water At high T it displays the
liquid-gas phase transition [46ndash525556] (Figure 2) At fixed temperature for increasing
Water and anomalous liquids 7
Figure 2 Density ρ as function of temperature T along isobars for the model in Eq(5) Labels near each isobar show the corrisponding pressure P in units of εv0 (a) Athigh temperature the discontinuity in ρ marks the liquid-gas phase transition endingin a critical point The black line represents the locus of maximum density (b) Atlow T another discontinuity in ρ marks the phase transition between HDL and LDLDashed lines approximate the coexistence regions [52]
pressure the diffusion constant increases up to a maximum reproducing the anomalous
behavior of diffusion a characteristic of water By decreasing P at constant T KT
αP and CP increase in a way that is not expected for normal liquids These anomalies
become more evident approaching the supercooled region of the phase diagram As a
rationale to this phenomena various scenarios have been proposed
The stability limit scenario [57] hypothesizes that the locus of the limit of stability
of superheated liquid water in PndashT plane have a positive slope at high T Decreasing
T this locus reaches a minimum pressure and for further decrease of T it acquires a
negative slope at low T The reentrant behavior of this locus would be consistent with
the observed anomalies of water
The liquid-liquid critical point (LLCP) scenario [39] supposes that the anomalies of
water are due to the large fluctuations of thermodynamics quantities as a consequence of
a first order phase transition in the supercooled region between two metastable liquids
at different densities the low-density liquid (LDL) at low P and low T and the high-
density liquid (HDL) at high P and high T The phase transition line ends in a critical
point and has a negative slope in the P minus T plane because the entropy is higher in the
HDL phase
Water and anomalous liquids 8
Figure 3 By mapping the system in the space of parameters J and Jσ Stokelyet al [56] recover all the scenarios proposed to explain the anomalous behavior ofsupercooled water (i) If Jσ = 0 (red line along x-axis) independently of J we recoverthe singularity-free scenario (ii) For large enough Jσ (yellow region in top left) waterexhibits a first-order liquid-liquid phase transition line terminating at the LiquidGasspinodal as predicted in the critical-point-free scenario (iii) For other combinations ofJ and Jσ water would be described by the LLCP scenario For larger Jσ the LLCP isat negative pressure (brown region between dashed lines) For smaller Jσ the LLCPis at positive pressure (orange region in bottom right)
The singularity-free scenario [53] predicts lines of maximum in the P minus T for the
response functions similar to those observed in the LLCP scenario but shows that no
singularities are present for non-zero temperatures
The critical-point-free scenario [41] hypothesizes an order-disorder transition
extending to negative pressure and reaching the supercooled limit of stability of liquid
water This scenario predicts no critical point and a behavior for the limit of stability
of liquid water as in the stability limit scenario
It is possible to map all these scenarios in the Hamiltonian model proposed by
Franzese and Stanley [Eq (5)] tuning the coupling constants J (for the covalent
component of the HBs) and Jσ (for the many-body component of the HB interaction) [56]
(Figure 3) The absence of the many-body component leads to the singularity free
scenario while a large value of the many-body component with respect to the covalent
component gives rise to the critical-point freestability limit scenario Intermediate
values of J and Jσ lead to the LLCP scenario All scenarios are obtained from the same
mechanism Estimating the parameters J and Jσ from the experiments we get Jσ sim 1
kJmol ε sim 55 kJmol and J sim 6minus 12 kJmol With this set of parameters the model
predicts the LLCP scenario with a liquid-liquid critical point C prime at positive pressure
Therefore the cooperative behavior of HBs is the principal responsible for the
anomalous behavior of water The model shows that the HB many-body component as
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 6
Figure 1 Schematic representation of the model Each cell can be empty or occupatedby a water molecule with oxigen (in red) hydrogens (in blue) and lone electrons pairrepresented by gray sticks To each hydrogen and lone pair we associate a bondingvariable σij
where Jσ gt 0 is the characteristic energy of this cooperative component
The formation of a HB leads to an open structure that induces a local increase
of volume per molecule This effect is incorporated in the model by considering that
the total volume of the system depends linearly on the number of HBs So the volume
change is
V equiv V0 + NHBvHB (4)
where vHB is the increment due to the HB and V0 equiv Nv0 for N water molecules
The total enthalpy for the water is
H equiv U + HHB + HCoop + PV = U minus (J minus PvHB)NHB minus JNσ + PV0 (5)
where the total number of HB and is
NHB equivsumltijgt
ninjδσijδσji
(6)
and
Nσ equivsum
i
sum(kl)i
δσikσil (7)
is the total number of HBs optimizing the cooperative interaction [46ndash525556]
3 Phase diagram and supercooled water
By both mean field and simulations we calculate the properties of the model in Eq
(5) It reproduces qualitatively the phase diagram of water At high T it displays the
liquid-gas phase transition [46ndash525556] (Figure 2) At fixed temperature for increasing
Water and anomalous liquids 7
Figure 2 Density ρ as function of temperature T along isobars for the model in Eq(5) Labels near each isobar show the corrisponding pressure P in units of εv0 (a) Athigh temperature the discontinuity in ρ marks the liquid-gas phase transition endingin a critical point The black line represents the locus of maximum density (b) Atlow T another discontinuity in ρ marks the phase transition between HDL and LDLDashed lines approximate the coexistence regions [52]
pressure the diffusion constant increases up to a maximum reproducing the anomalous
behavior of diffusion a characteristic of water By decreasing P at constant T KT
αP and CP increase in a way that is not expected for normal liquids These anomalies
become more evident approaching the supercooled region of the phase diagram As a
rationale to this phenomena various scenarios have been proposed
The stability limit scenario [57] hypothesizes that the locus of the limit of stability
of superheated liquid water in PndashT plane have a positive slope at high T Decreasing
T this locus reaches a minimum pressure and for further decrease of T it acquires a
negative slope at low T The reentrant behavior of this locus would be consistent with
the observed anomalies of water
The liquid-liquid critical point (LLCP) scenario [39] supposes that the anomalies of
water are due to the large fluctuations of thermodynamics quantities as a consequence of
a first order phase transition in the supercooled region between two metastable liquids
at different densities the low-density liquid (LDL) at low P and low T and the high-
density liquid (HDL) at high P and high T The phase transition line ends in a critical
point and has a negative slope in the P minus T plane because the entropy is higher in the
HDL phase
Water and anomalous liquids 8
Figure 3 By mapping the system in the space of parameters J and Jσ Stokelyet al [56] recover all the scenarios proposed to explain the anomalous behavior ofsupercooled water (i) If Jσ = 0 (red line along x-axis) independently of J we recoverthe singularity-free scenario (ii) For large enough Jσ (yellow region in top left) waterexhibits a first-order liquid-liquid phase transition line terminating at the LiquidGasspinodal as predicted in the critical-point-free scenario (iii) For other combinations ofJ and Jσ water would be described by the LLCP scenario For larger Jσ the LLCP isat negative pressure (brown region between dashed lines) For smaller Jσ the LLCPis at positive pressure (orange region in bottom right)
The singularity-free scenario [53] predicts lines of maximum in the P minus T for the
response functions similar to those observed in the LLCP scenario but shows that no
singularities are present for non-zero temperatures
The critical-point-free scenario [41] hypothesizes an order-disorder transition
extending to negative pressure and reaching the supercooled limit of stability of liquid
water This scenario predicts no critical point and a behavior for the limit of stability
of liquid water as in the stability limit scenario
It is possible to map all these scenarios in the Hamiltonian model proposed by
Franzese and Stanley [Eq (5)] tuning the coupling constants J (for the covalent
component of the HBs) and Jσ (for the many-body component of the HB interaction) [56]
(Figure 3) The absence of the many-body component leads to the singularity free
scenario while a large value of the many-body component with respect to the covalent
component gives rise to the critical-point freestability limit scenario Intermediate
values of J and Jσ lead to the LLCP scenario All scenarios are obtained from the same
mechanism Estimating the parameters J and Jσ from the experiments we get Jσ sim 1
kJmol ε sim 55 kJmol and J sim 6minus 12 kJmol With this set of parameters the model
predicts the LLCP scenario with a liquid-liquid critical point C prime at positive pressure
Therefore the cooperative behavior of HBs is the principal responsible for the
anomalous behavior of water The model shows that the HB many-body component as
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 7
Figure 2 Density ρ as function of temperature T along isobars for the model in Eq(5) Labels near each isobar show the corrisponding pressure P in units of εv0 (a) Athigh temperature the discontinuity in ρ marks the liquid-gas phase transition endingin a critical point The black line represents the locus of maximum density (b) Atlow T another discontinuity in ρ marks the phase transition between HDL and LDLDashed lines approximate the coexistence regions [52]
pressure the diffusion constant increases up to a maximum reproducing the anomalous
behavior of diffusion a characteristic of water By decreasing P at constant T KT
αP and CP increase in a way that is not expected for normal liquids These anomalies
become more evident approaching the supercooled region of the phase diagram As a
rationale to this phenomena various scenarios have been proposed
The stability limit scenario [57] hypothesizes that the locus of the limit of stability
of superheated liquid water in PndashT plane have a positive slope at high T Decreasing
T this locus reaches a minimum pressure and for further decrease of T it acquires a
negative slope at low T The reentrant behavior of this locus would be consistent with
the observed anomalies of water
The liquid-liquid critical point (LLCP) scenario [39] supposes that the anomalies of
water are due to the large fluctuations of thermodynamics quantities as a consequence of
a first order phase transition in the supercooled region between two metastable liquids
at different densities the low-density liquid (LDL) at low P and low T and the high-
density liquid (HDL) at high P and high T The phase transition line ends in a critical
point and has a negative slope in the P minus T plane because the entropy is higher in the
HDL phase
Water and anomalous liquids 8
Figure 3 By mapping the system in the space of parameters J and Jσ Stokelyet al [56] recover all the scenarios proposed to explain the anomalous behavior ofsupercooled water (i) If Jσ = 0 (red line along x-axis) independently of J we recoverthe singularity-free scenario (ii) For large enough Jσ (yellow region in top left) waterexhibits a first-order liquid-liquid phase transition line terminating at the LiquidGasspinodal as predicted in the critical-point-free scenario (iii) For other combinations ofJ and Jσ water would be described by the LLCP scenario For larger Jσ the LLCP isat negative pressure (brown region between dashed lines) For smaller Jσ the LLCPis at positive pressure (orange region in bottom right)
The singularity-free scenario [53] predicts lines of maximum in the P minus T for the
response functions similar to those observed in the LLCP scenario but shows that no
singularities are present for non-zero temperatures
The critical-point-free scenario [41] hypothesizes an order-disorder transition
extending to negative pressure and reaching the supercooled limit of stability of liquid
water This scenario predicts no critical point and a behavior for the limit of stability
of liquid water as in the stability limit scenario
It is possible to map all these scenarios in the Hamiltonian model proposed by
Franzese and Stanley [Eq (5)] tuning the coupling constants J (for the covalent
component of the HBs) and Jσ (for the many-body component of the HB interaction) [56]
(Figure 3) The absence of the many-body component leads to the singularity free
scenario while a large value of the many-body component with respect to the covalent
component gives rise to the critical-point freestability limit scenario Intermediate
values of J and Jσ lead to the LLCP scenario All scenarios are obtained from the same
mechanism Estimating the parameters J and Jσ from the experiments we get Jσ sim 1
kJmol ε sim 55 kJmol and J sim 6minus 12 kJmol With this set of parameters the model
predicts the LLCP scenario with a liquid-liquid critical point C prime at positive pressure
Therefore the cooperative behavior of HBs is the principal responsible for the
anomalous behavior of water The model shows that the HB many-body component as
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 8
Figure 3 By mapping the system in the space of parameters J and Jσ Stokelyet al [56] recover all the scenarios proposed to explain the anomalous behavior ofsupercooled water (i) If Jσ = 0 (red line along x-axis) independently of J we recoverthe singularity-free scenario (ii) For large enough Jσ (yellow region in top left) waterexhibits a first-order liquid-liquid phase transition line terminating at the LiquidGasspinodal as predicted in the critical-point-free scenario (iii) For other combinations ofJ and Jσ water would be described by the LLCP scenario For larger Jσ the LLCP isat negative pressure (brown region between dashed lines) For smaller Jσ the LLCPis at positive pressure (orange region in bottom right)
The singularity-free scenario [53] predicts lines of maximum in the P minus T for the
response functions similar to those observed in the LLCP scenario but shows that no
singularities are present for non-zero temperatures
The critical-point-free scenario [41] hypothesizes an order-disorder transition
extending to negative pressure and reaching the supercooled limit of stability of liquid
water This scenario predicts no critical point and a behavior for the limit of stability
of liquid water as in the stability limit scenario
It is possible to map all these scenarios in the Hamiltonian model proposed by
Franzese and Stanley [Eq (5)] tuning the coupling constants J (for the covalent
component of the HBs) and Jσ (for the many-body component of the HB interaction) [56]
(Figure 3) The absence of the many-body component leads to the singularity free
scenario while a large value of the many-body component with respect to the covalent
component gives rise to the critical-point freestability limit scenario Intermediate
values of J and Jσ lead to the LLCP scenario All scenarios are obtained from the same
mechanism Estimating the parameters J and Jσ from the experiments we get Jσ sim 1
kJmol ε sim 55 kJmol and J sim 6minus 12 kJmol With this set of parameters the model
predicts the LLCP scenario with a liquid-liquid critical point C prime at positive pressure
Therefore the cooperative behavior of HBs is the principal responsible for the
anomalous behavior of water The model shows that the HB many-body component as
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 9
large as can be deduced from experiments implies a LLCP
4 Water confined between hydrophobic surfaces
Franzese and los Santos studied the dynamics of water confined between hydrophobic
plates at low temperature [52] They observed different behaviors of water at different
pressures At very high pressure the formation of HBs is inhibited and the system
exhibits large cavities at low T due to the condensation of water molecules on the
hydrophobic surface At higher T the system is quite homogeneous in a wide range of
temperature In this case the time correlation function C(t) that quantifies the time
in which the HBs of two water molecules are statistically correlated has an exponential
decay In general
C(t) = C0eminus( t
τ )β
(8)
where C0 τ and β le 1 are fitting constant (β = 1 correspond to exponential decay)
For pressure close to the critical pressure PCprime the time correlation function has an
exponential decay for high temperature far from the LLCP temperature TCprime As we
approach TCprime the time correlation function is well described by a stretched exponential
(β lt 1) The study shows observe that the network of HBs is well developed already
in the high density phase but has no global order Approaching TCprime the effect of
cooperativity results in a strong heterogeneity in the system The value predicted for the
stretched exponential β that quantifies the degree of deviation from homogeneity of the
system is in agreement with experimental results on water hydrating myoglobin [5859]
Further decrease of pressure and temperature leads the system to a glassy state with
a strong HB network that traps the system in arrested configurations As a consequence
the time correlation function has a constant value close to one
5 Percolating approach
The analysis of the system with a percolating approach allow us to understand better the
formation of the HB network [60] We define a cluster as the region of the statistically
correlated water molecules connected by HBs in a tetrahedral state [6162] Simulations
and mean field calculations show how the network of HBs percolates in the system as
we approach to the critical point C prime (Figure 4) As a consequence the tetrahedral order
of the water molecules increases [55 63] Large fluctuations if the number of HBs are
observed in the region of the Widom line (the region of the phase diagram where the
system has a maximum correlation length) [4951] The large fluctuations of the number
of HBs indicate the occurrence of a macroscopic structural change from HDL-like liquid
to LDL-like liquid
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 10
Figure 4 Water monolayer between two hydrophobic slabs (not showed in the figure)Each water molecule is represented by four sites at the vertices of a square lattice Thevertices are situated at the center of the square partion used to represent the systemEach site of a molecule represents a bonding variable σij Sites with the same colorare in the same bonding state and at the same time are statistically correlated
6 Dynamical crossover
As we already mentioned at low T the model predicts an arrested state This is
consistent with experiments for water that glassifies rapidely if quenched at very low
T By definition the relaxation time τ of the system changes greatly as we approach
the glassy temperature reaching 100 sec at the glassy temperature A liquid systems is
said to be Arrhenius if τ depends exponentially on 1T as
τ = τ0eEAkBT (9)
The quantity EA is the activation energy kB is the Boltzmann constant and τ0 the
characteristic relaxation time for T rarr infin The liquids that deviate from this relation
are classified as non-Arrhenius
Kumar et al [50] using this model find a dynamic crossover for the correlation
time τ of the HBs from non-Arrhenius behavior at high T to Arrhenius behavior at
low T They show that this behavior is independent on the existence of a LLCP This
crossover corresponds to a local rearrangement of the HBs for the formation of more
tetrahedral structure From the low T Arrhenius behavior of the correlation time the
authors estimate the T -independent activation energy EA Furthermore by mean field
calculations they are able to show that for T greater than the temperature of the Widom
line a decrease of T leads to an increase of the number of HBs and to an increase of the
EA For T lower that the temperature of the Widom line the number of HBs and EA
remains constant upon further decreasing of temperature Therefore they show that
the crossover occurs exactly at the Widom line They find also that the crossover is
isochronic ie occurs when the system reaches a characteristic correlation time that is
independent of the pressure The predictions are in agreement with the experiments on
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 11
the hydrated lysozyme [64]
Mazza et al show that the model predicts also another crossover at lower T for
the HBs correlation time This second crossover is experimentally observed in lysozyme
hydration water [65] At low P two structural changes take place in the HB network of
the hydration shell One at about 250 K is due to the building up of the HB network
and another at about 180 K is consequence of the cooperative reorganization of the HBs
Both crossovers are related to the two maxima found by the authors for the heat capacity
of the system [66] for low pressure These two maxima are due to the fluctuations of
the tetrahedral order and to the fluctuations in HB formation For increasing pressure
the two maxima merge and give rise to a single locus that approaches the Widom line
7 Liquid-liquid phase transitions
In recent years several experiments have shown the occurrence of a liquid-liquid phase
transition in different substances such as phosphorus [7 8] liquid metals Y2O3-Al2O3
(Yttrium OxideAluminum Oxide Melts) [34] and molecular liquids [31] Molecular
dynamics simulations of specific models for supercooled water [2 39 43 67ndash69] liquid
carbon [70] and supercooled silica [3 4 7172] predict LDL-HDL critical point
To describe simple atomic systems (like argon) an isotropic pair interaction
potential is commonly used Probably the most famous potential is the one proposed
in 1931 [73] by John Edward Lennard-Jones (LJ) for real gases The LJ potential
incorporates the van der Waals attraction due to the instantaneous formation of dipoles
between the electronic clouds and the short range repulsion due to the Paulirsquos quantum
exclusion principle among electron orbitals The LJ potential reproduces a phase
diagram with gas liquid and solid phases for simple atomic or molecular systems
Moreover the dynamics and kinetics of these systems are correctly described
Simple variation of LJ were used to describe more complex system like colloids
or protein solutions However with this kind of potential is not possible to reproduce
anomalous properties of systems like liquid metals or water
All the system we talked about are network-forming substances with strongly
anisotropic interactions However it is possible to describe the anomalous properties
of some substances considering a soft-core isotropic potential with two characteristic
lengths [1974ndash78]
Franzese et al [79] show that a spherically symmetric potential with an attractive
interaction at long distance a repulsive soft-core at intermediate distance and a hard-
core repulsion at short distance can describe a single component system with a first-
order liquid-liquid phase transitions The simplest approximation for such kind of
potential is a square potential as showed in Figure 5
In particular they showed that a system with this potential has a gas-liquid critical
point and a liquid-liquid critical point for a certain range of potential parameters
They find that a balance between the attractive and repulsive part of the potential
leads to the existence of two fluid-fluuid critical points well separated in temperature
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 12
-1
0
1
2
3
4
UU
A
0 05 1 15 2 25 3
ra
1530100300500
RRa
URU
A (RA-R
R)a
∆
Figure 5 Potentials with two characteristic lengths the continuous shouldered wellpotential (continuous lines) and the discontinuous shouldered well potential (dottedblack line) The parameter ∆ estabilishes the slope of the shoulder between r = a andr = 2a
and density [80] This behavior can be qualitatively reproduced by a modified van der
Waals equation [81]
P =ρkBT
1minus ρB(ρ T )minus Aρ2 (10)
where A represents the strength of attraction and B the excluded volume This equation
has the same form of the van der Waals equation but with an excluded volume B(ρ T )
depending on density and temperature B(ρ T ) varies between the hard-core value for
high temperature and the soft-core value for low temperature
They also show that with the discontinuous version of the potential the occurrence
of the the liquid-liquid phase transition does not imply the presence of density anomaly
[76] Nevertheless a continuous version of the soft-core potential exhibits water-like
anomalies In particular it has been shown that density anomaly [82] anomalous
diffusion and anomalous structures [83] occur in a water-like hierarchy Furthermore
the extension and accessibility of the anomalous region depends on the softness of the
potential [84]
8 Conclusions
The results shortly presented here allows us to formulate possible answers to the
questions asked at the beginning of this review
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 13
(i) We clarify that directional bonding is not the only possible mechanism for the
anomalies The anomalies can be related both to bonding and to two competing
interaction distances
(ii) We understand that anomalies imply a liquid-liquid phase transition in the sense
that the mechanism responsible for the anomalies (eg hydrogen bonding for water
or competing interaction distances for liquid metals) are enough to generate a
liquid-liquid phase separation Nevertheless if the iquid-liquid phase coexistence is
reachable or not in experiments is a question more complex to answer In the case of
water it is evident from experiments that the phase separation cannot be observed
in the bulk because it is predicted by models in a region where only solid water
(amorphous or crystal ice) exists Confinement can reduce the tendency of water
to solidify but can also change drastically the thermodynamics of water [85] In
other cases eg phosphorous the liquid-liquid phase separation is experimentally
accessible but experiments cannot be performed in the region where a possible
liquid-liquid critical point would be [7ndash9]
(iii) We clarify that a liquid-liquid phase transition would not necessarly imply an
anomalous behavior because there is at least one case for a theoretical model [76]
in which this has been shown
(iv) We understand how to write a microscopic theory for this phenomena for both
possible mechanisms proposed here For the case of directional bonding as in
water a Hamiltonian model allows us to make analytic calculations and perform
efficient numerical simulations that amke possible to interpret in a clear way the
experimental results for supercooled water For the case of competing interaction
distances as in liquid metals or colloids we can develop a theory and make
simulations for an isotropic model
(v) With these models we can predict new phenomena such as the occurrence of a
sequence of partial structural changes in protein hydration water corresponding to
different maxima in the heat capacity and to different crossover in the relaxation
dynamics [65] Or to predict how the pressure would affect the thermodynamics
of nanoconfined water [85] or the dynamics of protein hydration water [86] These
results are potentially relevant in many applicative fields such as criobiology or
nanomedicine
Acknowledgments
We thank for discussions and collaboration M C Barbosa S V Buldyrev F Bruni S-
H Chen A Hernando-Martınez P Kumar G Malescio F Mallamace M I Marques
M G Mazza A B de Oliveira S Pagnotta F de los Santos H E Stanley K Stokely
E G Strekalova P Vilaseca We thank the Spanish Ministerio de Ciencia e Innovacion
Grants FIS2009-10210 (co-financed FEDER) and V B thanks the Generalitat de
Catalunya Grant 2010 FI-DGR for support
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 14
[1] Angell CA Borick S Grabow M (1996) Glass transitions and first order liquid-metal-to-semiconductor transitions in 4-5-6 covalent systems Journal of Non-Crystalline Solids 205-207463ndash471
[2] Poole PH Hemmati M Angell CA (1997) Comparison of thermodynamic properties of simulatedliquid silica and water Physical Review Letters 79 2281-2284
[3] Lacks DJ (2000) First-order amorphous-amorphous transformation in silica Physical ReviewLetters 84 4629-4632
[4] Saika-Voivod I Sciortino F Poole PH (2000) Computer simulations of liquid silica Equation ofstate and liquidndashliquid phase transition Physical Review E 63 011202
[5] Sastry S Austen Angell C (2003) Liquid-liquid phase transition in supercooled silicon NatureMaterials 2 739-743
[6] Brazhkin VV Popova SV Voloshin RN (1997) High-pressure transformations in simple meltsHigh Pressure Research 15 267ndash305
[7] Katayama Y Mizutani T Utsumi W Shimomura O Yamakata M et al (2000) A first-orderliquid-liquid phase transition in phosphorus Nature 403 170ndash3
[8] Katayama Y Inamura Y Mizutani T Yamakata M Utsumi W et al (2004) Macroscopicseparation of dense fluid phase and liquid phase of phosphorus Science 306 848-851
[9] Monaco G Falconi S Crichton WA Mezouar M (2003) Nature of the first-order phase transitionin fluid phosphorus at high temperature and pressure Physical Review Letters 90 255701
[10] Debenedetti PG (1996) Metastable Liquids Concepts and Principles Princeton NJ PrincetonUniversity Press
[11] Hare DE Sorensen CM (1986) Densities of supercooled h2o and d2o in 25 mu glass capillariesThe Journal of Chemical Physics 84 5085-5089
[12] Speedy RJ Angell CA (1976) Isothermal compressibility of supercooled water and evidence for athermodynamic singularity at -45 C Journal of Physical Chemistry 65 851-858
[13] Angell CA Sichina WJ Oguni M (1982) Heat capacity of water at extremes of supercooling andsuperheating Journal of Physical Chemistry 86 998-1002
[14] Mon KK Ashcroft NW Chester GV (1979) Core polarization and the structure of simple metalsPhysical Review B 19 5103ndash5122
[15] P L S S W K (1976) Structure of molten bi-sb-alloys by means of neutron diffraction ZeitschriftNaturforschung Teil A 31 90
[16] Thurn H Ruska J (1976) Change of bonding system in liquid sexte1-1 alloys as shown by densitymeasurements Journal of Non-Crystalline Solids 22 331-343
[17] Sauer GE Borst LB (1967) Lambda transition in liquid sulfur Science 158 1567-1569[18] Kennedy SJ Wheeler JC (1983) On the density anomaly in sulfur at the polymerization transition
The Journal of Chemical Physics 78 1523-1527[19] Wax JF Albaki R Bretonnet JL (2002) Temperature dependence of the diffusion coefficient in
liquid alkali metals Physical Review B 65 014301[20] Angell CA Bressel RD Hemmati M Sare EJ Tucker JC (2000) Water and its anomalies in
perspective tetrahedral liquids with and without liquid-liquid phase transitions invited lecturePhysical Chemistry Chemical Physics 2 1559-1566
[21] Sharma R Chakraborty SN Chakravarty C (2006) Entropy diffusivity and structural order inliquids with waterlike anomalies The Journal of Chemical Physics 125 204501
[22] Shell MS Debenedetti PG Panagiotopoulos AZ (2004) Saddles in the energy landscapeExtensivity and thermodynamic formalism Physical Review Letters 92 035506
[23] Angell CA Finch ED Bach P (1976) Spinndashecho diffusion coefficients of water to 2380 bar and -20
C The Journal of Chemical Physics 65 3063-3066[24] Errington JR Debenedetti PG (2001) Relationship between structural order and the anomalies of
liquid water Nature 409 318-321[25] Mishima O Calvert L Whalley E (1985) An apparently 1st-order transition between 2 amorphous
phases of ice induced by pressure Nature 314 76-78
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 15
[26] Mishima O (1994) Reversible first-order transition between two H2O amorphs at sim 02 GPa andsim 135 K The Journal of Chemical Physics 100 5910-5912
[27] Mishima O (1996) Relationship between melting and amorphization of ice Nature 384 546-549[28] Mishima SY Osamu (2002) Propagation of the polyamorphic transition of ice and the liquid-liquid
critical point Nature 419 599-603[29] Mishima O Stanley HE (1998) The relationship between liquid supercooled and glassy water
Nature 396 329ndash335[30] Franzese G Stanley HE (2010) Understanding the unusual properties of water In Lynden-Bell
RM Conway Morris S Barrow JD Finney JL Harper C editors Water and Life The UniqueProperties of H20 CRC Press URL httpdxdoiorg101201EBK1439803561-c7
[31] Kurita R Tanaka H (2004) Critical-like phenomena associated with liquid-liquid transition in amolecular liquid Science 306 845-848
[32] Tanaka H Kurita R Mataki H (2004) Liquid-liquid transition in the molecular liquid triphenylphosphite Physical Review Letters 92 025701
[33] Kurita R Tanaka H (2005) On the abundance and general nature of the liquid-liquid phasetransition in molecular systems Journal of Physics Condensed Matter 17 L293
[34] Greaves GN Wilding MC Fearn S Langstaff D Kargl F et al (2008) Detection of first-orderliquidliquid phase transitions in yttrium oxide-aluminum oxide melts Science 322 566-570
[35] Bruggeller P Mayer E (1980) Complete vitrification in pure liquid water and dilute aqueoussolutions Nature 288 569-571
[36] Finney JL Bowron DT Soper AK Loerting T Mayer E et al (2002) Structure of a new denseamorphous ice Physical Review Letters 89 205503
[37] Kanno H Speedy RJ Angell CA (1975) Supercooling of water to -92 C under pressure Science189 880-881
[38] Soper A Ricci M (2000) Structures of high-density and low-density water Physical Review Letters84 2881-2884
[39] Poole P Sciortino F Essmann U Stanley H (1992) Phase-behavior of metastable water Nature360 324-328
[40] Stanley HE Teixeira J (1980) Interpretation of the unusual behavior of H2O and D2O at lowtemperatures Tests of a percolation model The Journal of Chemical Physics 73 3404ndash3422
[41] Angell CA (2008) Insights into phases of liquid water from study of its unusual glass-formingproperties Science 319 582ndash587
[42] Brovchenko I Geiger A Oleinikova A (2005) Liquid-liquid phase transitions in supercooled waterstudied by computer simulations of various water models The Journal of Chemical Physics 123044515
[43] Liu Y Panagiotopoulos AZ Debenedetti PG (2009) Low-temperature fluid-phase behavior of ST2water The Journal of Chemical Physics 131 104508
[44] Vilaseca P Franzese G (2011) Isotropic soft-core potentials with two characteristic length scalesand anomalous behaviour Journal of Non-Crystalline Solids 357 419-426
[45] Molinero V Moore EB (2009) Water modeled as an intermediate element between carbon andsilicon The Journal of Physical Chemistry B 113 4008ndash4016
[46] Franzese G Stanley HE (2002) A theory for discriminating the mechanism responsible for thewater density anomaly Physica A Statistical Mechanics And Its Applications 314 508ndash513
[47] Franzese G Stanley HE (2002) Liquid-liquid critical point in a hamiltonian model for wateranalytic solution Journal of Physics Condensed Matter 14 2201ndash2209
[48] Franzese G Marques MI Stanley HE (2003) Intramolecular coupling as a mechanism for a liquid-liquid phase transition Physical Review E 67 011103
[49] Franzese G Stanley HE (2007) The widom line of supercooled water Journal of PhysicsCondensed Matter 19 205126
[50] Kumar P Franzese G Stanley HE (2008) Predictions of dynamic behavior under pressure for twoscenarios to explain water anomalies Physical Review Letters 100 105701
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 16
[51] Franzese G Hernando-Martınez A Kumar P Mazza MG Stokely K et al (2010) Phase transitionsand dynamics of bulk and interfacial water Journal of Physics Condensed Matter 22 284103
[52] Franzese G de los Santos F (2009) Dynamically slow processes in supercooled water confinedbetween hydrophobic plates Journal of Physics Condensed Matter 21 504107
[53] Sastry S Debenedetti PG Sciortino F Stanley HE (1996) Singularity-free interpretation of thethermodynamics of supercooled water Physical Review E 53 6144ndash6154
[54] Ricci MA Bruni F Giuliani A (2009) Similarities between confined and supercooled waterFaraday Discussions 141 347-358
[55] Mazza MG Stokely K Strekalova EG Stanley HE Franzese G (2009) Cluster monte carlo andnumerical mean field analysis for the water liquid-liquid phase transition Computer PhysicsCommunications 180 497-502
[56] Stokely K Mazza MG Stanley HE Franzese G (2010) Effect of hydrogen bond cooperativity onthe behavior of water Proceedings of the National Academy of Sciences of the United Statesof America 107 1301ndash1306
[57] Speedy RJ (1982) Limiting forms of the thermodynamic divergences at the conjectured stabilitylimits in superheated and supercooled water The Journal of Physical Chemistry 86 3002ndash3005
[58] Settles M Doster W (1996) Anomalous diffusion of adsorbed water A neutron scattering studyof hydrated myoglobin Faraday Discussions 103 269-279
[59] Doster W (2010) The protein-solvent glass transition Biochimica et Biophysica Acta 1804 3-14[60] Bianco V Iskrov S Franzese G (2011) Understanding the role of hydrogen bonds on water dynamics
and protein stability Accepted on Journal of Biological Physics [61] Coniglio A Klein W (1980) Clusters and ising critical droplets a renormalisation group approach
Journal of Physics A Mathematical and General 13 2775[62] Fortuin CM Kasteleyn PW (1972) On the random-cluster model i introduction and relation to
other models Physica 57 536-564[63] Franzese G Bianco V Iskrov S (2011) Water at interface with proteins Food Biophysics 6
186-198[64] qiang Chu X Faraone A Kim C Fratini E Baglioni P et al Pressure dependence of the dynamic
crossover temperatures in protein and its hydration water URL httparXiv08101228v1[65] Mazza MG Stokely K Pagnotta SE Bruni F Stanley HE et al (2009) Two dynamic
crossovers in protein hydration water and their thermodynamic interpretation URL http
arxivorgabs09071810[66] Mazza MG Stokely K Stanley HE Franzese G (2008) Anomalous specific heat of supercooled
water URL httparxivorgabsarXiv08074267[67] Mishima O (2000) Liquid-liquid critical point in heavy water Physical Review Letters 85 334ndash
336[68] Peter H Poole ISV Sciortino F (2005) Density minimum and liquidliquid phase transition
Journal of Physics Condensed Matter 17[69] Abascal JLF Vega C (2010) Widom line and the liquidndashliquid critical point for the tip4p2005
water model The Journal of Chemical Physics 133 234502[70] Glosli JN Ree FH (1999) Liquid-liquid phase transformation in carbon Physical Review Letters
82 4659-4662[71] Vasisht VV Saw S Sastry S (2011) Liquid-liquid critical point in supercooled silicon Nature
Physics 7 549-553[72] Sciortino F (2011) Liquid-liquid transitions Silicon in silico Nature Physics 7 523-524[73] Lennard-Jones JE (1931) Wave functions of many-electron atoms Mathematical Proceedings of
the Cambridge Philosophical Society 27 469-480[74] Stillinger FH Head-Gordon T (1993) Perturbational view of inherent structures in water Physical
Review E 47 2484ndash2490[75] Quesada-Perez M Moncho-Jorda A Martinez-Lopez F Hidalgo-Alvarez R (2001) Probing
interaction forces in colloidal monolayers Inversion of structural data The Journal of Chemical
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-
Water and anomalous liquids 17
Physics 115 10897-10902[76] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2001) Generic mechanism for
generating a liquid-liquid phase transition Nature 409 692ndash695[77] Jagla EA (1999) Core-softened potentials and the anomalous properties of water The Journal of
Chemical Physics 111 8980-8986[78] Jagla EA (2002) Boundary lubrication properties of materials with expansive freezing Physical
Review Letters 88 245504[79] Franzese G Malescio G Skibinsky A Buldyrev SV Stanley HE (2002) Metastable liquid-liquid
phase transition in a single-component system with only one crystal phase and no densityanomaly Physical Review E 66 051206
[80] Malescio G Franzese G Skibinsky A Buldyrev SV Stanley HE (2005) Liquid-liquid phasetransition for an attractive isotropic potential with wide repulsive range Physical Review E 71061504
[81] Skibinsky A Buldyrev SV Franzese G Malescio G Stanley HE (2004) Liquid-liquid phasetransitions for soft-core attractive potentials Physical Review E 69 061206
[82] Franzese G (2007) Differences between discontinuous and continuous soft-core attractive potentialsThe appearance of density anomaly Journal on Molecular Liquids 136 267
[83] de Oliveira AB Franzese G Netz PA Barbosa MC (2008) Waterlike hierarchy of anomalies in acontinuous spherical shouldered potential The Journal of Chemical Physics 128 064901
[84] Vilaseca P Franzese G (2010) Softness dependence of the anomalies for the continuous shoulderedwell potential The Journal of Chemical Physics 133 084507
[85] Strekalova EG Mazza MG Stanley HE Franzese G (2011) Large decrease of fluctuations forsupercooled water in hydrophobic nanoconfinement Phys Rev Lett 106 145701
[86] Franzese G Stokely K Chu XQ Kumar P Mazza MG et al (2008) Pressure effects in supercooledwater comparison between a 2d model of water and experiments for surface water on a proteinJournal of Physics Condensed Matter 20 494210
- An overview on anomalous liquids and water
-
- Thermodynamic anomalies
- Dynamic anomalies
- Structural anomalies and polymorphism
- A few questions
-
- An Hamiltonian model for water
- Phase diagram and supercooled water
- Water confined between hydrophobic surfaces
- Percolating approach
- Dynamical crossover
- Liquid-liquid phase transitions
- Conclusions
-