The Hg-Te (mercury-tellurium) system

S e c t i o n II: P h a s e D i a g r a m E v a l u a t i o n s

The Hg-Te (Mercury-Tellurium) System

E q u i l i b r i u m D i a g r a m

R.C. S h a r m a and Y.A. Chang Univers i ty o f Wisconsin-Madison

and C. Guminsk i

Univers i ty o f Warsaw

In the Hg-Te system, an essentially stoichiometric intermedi- ate phase (o~HgTe) is formed at 50 at.% Te; it melts congruently. There are two eutectic reactions--one each in the (Hg)-HgTe and HgTe-(Te) regions of the phase diagram. The assessed Hg-Te phase diagram (Fig. 1 and 2) is based on our

modeling and calculations. Most experimental data are in good agreement with thermodynamic modeling.

L i q u i d u s

The melting points of pure Hg and Te are-38.8290 and 449.57 ~ respectively. The Hg-Te liquidus was determined by [09Pel], [65Bre], [67Str], [71Paj], [71Dzi], [76Ste], [77Van], [80Har], and [84Her]. All these data are shown in Fig, 1 and 2,

Fig. 1

%%,1 ' i t I > , r ' , t I , I l l l IJMI

L "??"~ .gs~oc

~:3t3

-3B 8290~ ~(Hg)

L + eHgTe

[09Pel] [] [ 7 6 S t e ]

�9 [ 6 5 B r e ] o [ 7 7 V a n ]

- [~lDzi} ~-38 83~

(Hg) + ~HgTe

i

I

i I

' , , { ~ , : 1 1 1 I>< r , , l ) l [ ~ [ h l / i t J t t

v>~) :

• <<,

~ ( H g )

I~,~ : [11 19 : ~ : i ! i , i ,~1 �84 i

Assessed Hg-Te phase diagram. Calculated. - - continuous lines.

~h) ] , : )

~ 449 57~

~k

(Te)

338 Journal of Phase Equilibria Vol. 16 No. 4 1995

P h a s e D i a g r a m E v a l u a t i o n s : S e c t i o n II

Table 1 Assessed Hg-Te Liquidus Data

Composition, at. % Te Temperature,~

0 , 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0 . 1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0 , 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

] . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

tO . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

1 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

2 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

3 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

4 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

5 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

6 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

7 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

8 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

9 5 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

100 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

-38.8290

186

261

301

422

491

536

571

599

621

640

655

666

670

658

623

585

549

509

464

411

423

437

449.57

along with the assessed phase boundaries. Table 1 lists the assessed liquidus temperatures for selected compositions.

Critical evaluation and experimental details of the aforemen- tioned determinations were elaborated by [86Gum]. Using a polarographic technique, [82Gla] determined Te solubility in liquid Hg at 20 ~ the result obtained (1.4 x 10 .3 at.% "re) may be overestimated due to the short drop time of the Hg elec- trode. A value of 1 x 10 -4 at.% Te at 20 ~ is obtained by ex- trapolation of [71Dzi], [71Paj], and [84Her] data from higher temperatures.

Table 2 Solubility of rig in (Te)

Temperature, Solubility, ~ at. % Hg

2 7 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

320 .......................................

340 .......................................

370 .......................................

3 9 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

420 .......................................

4 4 0 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

0.003

0.017

0.54

1.36 1.25 0.68

0.34

From [63Abd].

Fig. 2

c

O

4 ~ �9

�9

W e i g h t [~erc:cnt T e l l u r i l l m o

/ < - + ! / v, 0 [71Paj]

! / / , x ~ �9 [~Str]

: oo i / + • [84Ho l ,~ / ' " o [ww~]

i / / L + aHgTe -

00

1 5 0

! i

r

I :2 :; .I '=, fi 5

[ i~ A l o n , i c I~c , :< , cn t T e ] l u x t u n ~

Assessed Hg-Te phase diagram up to 7 at.% 'le.

Journal of Phase Equilibria Vol. 16 No. 4 t995 339


S o l i d S o l u b i l i t i e s

[63Abd] determined the solubility of Hg in (Te) from 217 to 440 ~ (Table 2). The data of [63Abd] show a maximum solubility of - 1.36 at.% Hg at 370 ~ -40 ~ below the eutectic temperature (411 ~ where the solubility should normally be maximum. This casts some doubts on the reliability of the data. In the assessed phase diagram (Fig. 1), the maximum solubility of rig in (Te) is therefore tentatively shown to be - 1 at.% Hg at the eutectic temperature, based on the above data, decreasing continuously below it. More accurate measurements on the solubility of rig in (Te) are needed. [71 Ale] measured residual electric resistivity of solid Hg saturated with Te at -40 ~ and found that the solubility of Te in (Hg) is in the range 10 -4 to 10-3 at.% "re.

~-Ig're

~HgTe is essentially stoichiometric and melts congruently. The melting temperature of RHgTe as determined by different investigators is given in Table 3, along with the assessed value. Corresponding experiments were performed in closed cap- sules, but unfortunately most of the investigators did not spec- ify pressure during the c~HgTe melting.

[68Levi and [70Levl] estimated the deviation from stoichiometric composition of c~HgTe from electrical property measurements. The maximum solubility of Hg in o~HgTe was found to be -1.7 x 10-5 at.% around 350 ~ and that of Te in c~HgTe was reported to be -1.9 x 10 -2 at.% near the melting point of o~HgTe. These findings are in agreement with electrical resistivity measurements of [65Bre], who established that

Table 3 Melting Temperature of r

Temperature , Pressure, Reference ~ MPa

[ 5 8 C a r ] . . . . . . . . . . . . . . . . . . . . . . . . 6 8 0 . . .

[ 5 9 L a w ] . . . . . . . . . . . . . . . . . . . . . . 6 0 0 . . .

[ 6 0 R o d ] . . . . . . . . . . . . . . . . . . . . . . . 6 5 5 + 5 . . .

[ 6 0 W o o l ] . . . . . . . . . . . . . . . . . . . . 6 7 6 _+ 5 . . .

[ 6 0 U s a ] . . . . . . . . . . . . . . . . . . . . . . . 6 6 7 . . .

[ 6 1 B l a 2 ] . . . . . . . . . . . . . . . . . . . . . . 6 6 3 . . .

[ 6 3 J a y ] . . . . . . . . . . . . . . . . . . . . . . . . 6 7 0 _+ 3 . . .

[ 6 3 D e l ] . . . . . . . . . . . . . . . . . . . . . . . . 6 7 0 + 1 . . .

[ 6 4 G r o ] . . . . . . . . . . . . . . . . . . . . . . . 6 8 5 . . .

[ 6 5 B r e ] . . . . . . . . . . . . . . . . . . . . . . . . 6 7 0 _+ 2 1 . 2 5

[ 6 7 R a y ] . . . . . . . . . . . . . . . . . . . . . . . 6 6 6 _+ 3 . . .

[ 67S t r ] . . . . . . . . . . . . . . . . . . . . . . . . . 6 7 0 . . .

[ 6 8 S p e ] . . . . . . . . . . . . . . . . . . . . . . . 6 6 5 + 2 . . .

[ 6 8 V a n ] . . . . . . . . . . . . . . . . . . . . . . . 6 8 0 _+ 5 . . .

[ 7 0 L e v 1 ] . . . . . . . . . . . . . . . . . . . . . 6 6 8 ._.

[ 7 1 P a j ] . . . . . . . . . . . . . . . . . . . . . . . . 6 6 7 _+ 5 . . .

[ 7 3 V i a l . . . . . . . . . . . . . . . . . . . . . . . . 6 6 8 . . .

[ 7 6 S t e ] . . . . . . . . . . . . . . . . . . . . . . . . 6 6 8 +_ 1 1 .4 to 2 . 7

[ 7 6 K u z ] . . . . . . . . . . . . . . . . . . . . . . . 6 8 7 _+ 7 . . .

[ 7 9 B a b ] . . . . . . . . . . . . . . . . . . . . . . . 6 6 7 . . .

1 8 1 S z o ] . . . . . . . . . . . . . . . . . . . . . . . 6 6 9 . 5 _+ 1.7 . . .

[ 8 3 G a v ] . . . . . . . . . . . . . . . . . . . . . . . 6 5 6 _+ 15 . . .

[ 8 3 V e n ] . . . . . . . . . . . . . . . . . . . . . . . 6 7 0 _+ 3 . . .

[ 8 6 A s a l . . . . . . . . . . . . . . . . . . . . . . . 6 7 0 . . .

[ 8 6 B f i ] . . . . . . . . . . . . . . . . . . . . . . . . 6 7 1 ._.

Assessed . . . . . . . . . . . . . . . . . . . . . . 6 7 0 - 1.5

9 0 0 . . . . . . . . . I . . . . " ~ ' ' ~- . . . . . . . i . . . . . . . i

Fig. 3

�9 g-

D-

�9

800

700

GO0

#)00

400

3 0 0

200 !

I

IO0

�9 . . . . + - -+ - - -+_# s _ + # #.,

+ i \ + i

aHgTe ~ +

+-

flHgTe

)~ XRD [820no]

0 R e s i s t i v i t y [ 7 3 L a e ]

�9 DTA ~ [ 6 3 J a y ]

�9 Volume

0 0 :)

+

l

+ i

1 / %

[]

V

A

0

+

DTA [ 7 8 R o t ]

XRD [ 8 3 W e r ]

Compress ib i l i ty [ 4 0 B r i ]

R e s i s t i v i t y [ 6 i B l a ]

DTA [ 8 2 0 m e ]

P-Tphase diagram for HgTe.


Phase Diagram Evaluations: Section II

Table 4 Invariant Equilibria in the Hg-Te System

Composition, Temperature, Reaction Reaction at . % Te ~ type

L r H g . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

L ~-~ (Hg) + ~HgTe .................................................. ~10 -5

L ~ ccHgTe .............................................................

L ~-~ L1 + (xHgTe ..................................................... ~52.5

L ~-~ ccHgTe + (Te) ................................................... 83.5

L (-~ Te ....................................................................

0 --38.8290 Mel t ing

- 0 50 ~ -38 .8 Eutect ic

50 670 Congruen t melt ing

-55 .5 -49 .98 664 Monotect ic

49.98 - 9 9 411 Eutectic

100 449.57 Mel t ing

Table 5 Hg-Te Crystal Structure Data

Composition, Pearson Space Strukturbericht Phase at . % Te symbol group designation Prototype

(Hg) ......................................................................... 0

([3Hg) ....................................................................... 0

ccHgTe ...................................................................... 50

13HgTe(a) .................................................................. 50

"filgTe(b) .................................................................. 50

8HgTe(c) .................................................................. 50

eHgTe(d) .................................................................. 50

(Te) .......................................................................... 99 to 100

hR 1 R3m A 10 otHg

t 12 14/mmm A5 C~Pa

cF8 F-43m B3 ZnS (sphalerite)

hP6 P3121 B9 H g S

cF8 Fm3rn B 1 NaC1

t14 14m2 A5 [~Sn

? ? ? a distorted CsCI

hP3 P3121 A 8 TSe

(a) Between 1.4 and 8.0 GPa. (b) Between 8.0 and 11.5 GPa. (c) Above 11.5 GPa. (d) Above 38.1 GPa.

the ~HgTe homogeneity range was only about 0.01 at.% wide. The same authors found this range of 0.6 + 0.2 at.% in vapor pressure investigations at 488 ~ According to [63Del] differ- ential thermal analysis, the Hg excess in (~HgTe) approaches 0, but as much as 2.5 at.% Te may be dissolved in solid HgTe. The values derived from electrical properties seem to be more reliable. Finally [85Asa] found in electric resistance measurements that the HgTe homogeneity range is between 49.45 and 50.75, and 49.3 and 50.95 at.% Te at 200 and 400 ~ respectively.

I n v a r i a n t Equilibria

The eutectic reaction in the Hg-rich region is essentially de- generate (10-5 at.% Te and-38.8 ~ The literature data on the eutectic point in the HgTe-(Te) region are: 88 at.% Te at 400 ~ [09Pel], 83.5 at.% Te at 413 ~ [67Str], 91.2 at.% Te a t -410 ~ [70Levi], and 83.3 + 0.8 at.% Te at an unspecified temperature [82Wil]. The assessed values are given in Table 4.

[65Dell discovered a quite narrow liquid miscibility region between -52.5 and -55.5 at.% Te at the monotectic temperature of 664 + 2 ~ The observation was confirmed by [70Levi], but because many other investigators put this aside, the phe- nomenon needs precise reinvestigation.

Phase Equilibria Calculations

We calculated the Hg-Te phase diagram using the thermodynamic data described in the "Thermodynamics" section below. In our calculations, the mutual solid solubilities of Hg and Te are assumed to be zero, and ~HgTe is taken as a line compound. [71Paj], [81Tun], [82Kel], [82Kikl], [82Kik2], [82Tun], [88Bre], [89Sba], and [93Adr] also calculated the Hg-Te phase diagram using similar models.

c r y s t a l s t r u c t u r e s a n d L a t t i c e P a r a m e t e r s

Crystal structures and lattice parameters for Hg-Te phases are given in Tables 5 and 6, respectively. [68Sni] measured the lattice parameter of aHgTe as a function of temperature from 77 to 300 K and observed linear dependence of this parameter on temperature between 140 and 290 K. The majority of data in Table 6 that were obtained earlier than 1959 are too low or not precise. Although the accepted value for aHgTe by ASTM is 0.6453 nm, many other precise determinations point rather to 0.6459 nm, and the purity of ~HgTe is not as critical [68Iva]. [90Nas] showed that bonding in c~HgTe is substantially cova- lent, but their lattice spacing result is too different to be accepted.

[63Mar], [82Ono], [83Hua], and [83Wer] investigated crystal- lographic properties of the high-pressure allotropic forms of HgTe at room temperature. The structure of 8HgTe was pri- marily ascribed as orthorhombic by [83Hua] and [85Ono], and finally as tetragonal by [83Wer] and [85Hua]. A distorted CsC1 type was ascribed to eHgTe above 38.1 GPa [85Hua]. The mat- ter needs further experiments in order to be resolved completely; see also "Pressure." [54Zor] used electron diffraction, and the rest of the investigators did XRD analysis of powders.

T h e r m o d y n a m i c s

Pure Components, The enthalpies of melting given by [Hultgren, E] were used to obtain the Gibbs energy functions for the melting of pure Hg and Te as:

Journal of Phase Equilibria Vol. 16 No. 4 1995 341

S e c t i o n II: P h a s e Diagram Eva lua t ions

Table 6 Hg-Te Lattice Parameter Data

Composition, Phase at. % Te

Lattice parameters, nm a b c

Temperature, Pressure,, ~ GPa Reference

Hg ................................. 0 0.3005

~Hg ............................... 0 0.3995

~HgTe ........................... 50 0.644

0.645

0.637

0.6447

0.6429

0 .6460

0.64623

0.64615

0.646

0.647

0.645

0 .6459

0.645

0.6445(a)

0.6430(b)

0.644

0.64588(c)

0.64595(d)

0.64557

0 .64606

0.6462

49.5 0 .6450

50.0 0.6502

50.8 0 .6610

0.6453

0 .6453

50 0.6460(2)

0.6386

0 .64608

~HgTe ........................... 50 0.446

0.445

0A28

yttgTe . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 0,5843

0.583

0.580

0.5795

8HgTe ........................... 50 0.5524

0,568

eHgTe . . . . . . . . . . . . . . . . . . . . . . . . . . . 50 0 .3339

Te .................................. 100 0.44566

0.3611

= 70.53 ~ 4 8 ,.. [King l ]

0.2825 - 196 0 [Pearson2]

. , , R T . . . [26Dej]

. . . R T . . . [26Har]

. . . R T . . . [26Zacl ]

. . R T ~ . . [26Zac2]

. . . R T , . . [54Zor]

. . . R T . . , [59Law]

... 25 . , . [61Bla2]

... RT . . . [60Woo 1 ]

. . . R T . . . [60Woo2, 60Woo3]

. . . R T . . . [62Gor]

,.. RT . . , [61 Rod]

. . . R T . . . [63Del]

. . . R T . . . [63Marl

. . . R T . . . [64Kru]

. . . R T . . . . . .

. . . R T , . . [64Sil]

. . . R T . . . [681va]

._ RT . . . . . .

. . . . 190 . . . [68Sni]

. . . 18 . . . . . .

. . . R T . , . [68Spe]

... 200 , . . [85Asa]

.., 200 ... [85Asa]

.., 200 ,.. [85Asa]

�9 . . R T . . . [83Hua]

. . . R T . . o [83Wer]

, . . R T . . . [86Leul

. . , R T . . . [90Nas]

... 120 ... [9 lBre]

0.917 R T 2.0 [63Mar]

0.989 R T 2.6 [83Wer]

0.963 R T 7.6 . . .

... 28 8.96 [83Hua, 85Hual

. . . R T 8.2 [83Wer]

. . . R T 10.5 ...

. . . R T 9.5 [82Ono]

0,2973 28 17.0 [85Hua]

0.304 R T 11.7 [83Wer]

0 .3284 28 41.0 [85Hua]

0 .59268 25 ... [King l ]

(a) Single crystal determination, (b) Powder determination. (c) Concentra t ion o f acceptors (8 to 9) x 1014 cm 3. (d) Concentra t ion o f acceptors (0.3 to 3) x 108 cm 3

AfusG~ = 2295 - 9.793 TJ/mol (Eq 1)

and

ArusG~ = 17 489 - 24.20 TJ/mol (Eq 2)

where Tis in K.

Liquid. [65Bre] measured the equilibrium partial pressures of Hg(g) and Te2(g ) along the Hg-Te liquidus. These data may be converted into the activities of rig and Te in the liquid at the

liquidus compositions. There are no other data available on the thermodynamic properties of the liquid phase.

We used an associated solution model to describe the thermodynamic properties of the liquid. According to this model, the liquid consists of"Hg," "Te," and "HgTe" species governed by the following equilibrium equation [79Sha]:

"Hg"(L) + "Te"(L) 6-~ "HgTe"(L)

with an equilibrium constant, K, given by:

(Eq 3)


P h a s e D i a g r a m E v a l u a t i o n s : S e c t i o n 11

Fig. 4

' ] ' (q '* / I ) ( ' r 'o,[ 1.1 "co " ( '

1 : . . . . . . . , , , , . . . . . . . . . r . . . .

! 4

! �9 [ssm-o]

~_ ~ i ~s

2 t . . . . ~ . . . . . . . . . . . . . . . . - . . . . . . I . . . . . . . .

1 0 l l t ? . 1 3 i 4 1 5

[04/'T(K) Equilibrium partial pressure (Prig) of Hg(g) along the Hg-Te liquidus.

T e m p e r ' a t u r ' c C

Fig. 5

'~~ _ . . �9 t65Bre]

I 0 11 1 2 1 3 1 4 l h

10 4 T(K)

Equilibrium partial pressure (PTe2) ~ along the Hg-Te liquidus.

K - ~ 3

0elYl) (f2Y2) (Eq 4)

whereJl,f2, and f3 are the activity coefficients, and Yl, Y2, and Y3 are the mole fractions of "Hg," "Te," and "HgTe," respectively, in the liquid. The mole fractions (Yi'S) are related to the

Journal of Phase Equilibria Vol, 16 No. 4 1995 343

S e c t i o n II: Phase Diagram Eva luat ions

actual mole fractions (XHg and Xxe) of Hg and Te, respectively, by the following mass balance equations:

Yl = XHg -- XTeY3 (Eq 5)

and

Y2 = xa'e - XHgY3 (Eq 6)

The Hg-Te liquid is now considered pseudoternary solution of "Hg," "Te," and "HgTe," whose excess Gibbs energy function of mixing is expressed by the quasi-regular solution model, so that:

AG e• R T - w12YlY2 + wl3YlY3 + w2~2Y3 (Eq 7)

where the interaction parameters wij are:

A 0 Wi) = -7- + Bij (Eq 8)

where Ai) and Bij are constants. The activity coefficients fl,f2, andf~ are then:

lnfj : wlzY ~ + w l ~ ~ + y2y3(w13 + wl2 - w23 ) (Eq 9)

and

l n f 2 = w12Y 2 + w23Y ~ + ylY3(Wl2 + w23 - w13 ) (Eq 10)

and

l n f ~ = w l ~ + w 2 ~ Z + y t y 2 ( w 1 3 + w 2 3 - w 1 2 ) (Eq 11)

The activities a I and a2 of"Hg" and "Te" species in the liquid are :

al =flYl (Eq 12)

and

a2 :f2Y2 (Eq 13)

where Hg(L) and Te(L) are the standard states. Because the activities of "Hg" and "Te" species are the same as those of the Hg and Te components [65Pri]:

a l = f l Y 2 = a u g = ~/HgXHg (Eq 14)

and

a2 =f2Y2 = aTe = ]/TeXTe (Eq 15)

where "gug and YTe are the activity coefficients of rig and Te that are different from fl and f2.

The optimum values of the different parameters of the liquid (Table 7) were obtained from the available thermodynamic and phase equilibria data for the Hg-Te system.

Table 7 Thermodynamic Data for the Hg-Te Liquid

"Hg"(L) + "Te"(L) <---> "HgTe"(L)

K = f3y3 OqY 1)(f2y2)

5767.56 In K : -3.81228 + - -

T

6338.6 w13 = 4 . 8 5 2 6 +

1424,0 w23 = ~3.3298 +

1331.9 w12 T

Note: Subscript 1 = "Hg" species. Subscript 2 = "Te" species. Subscript 3 = "HgTe" species.

The calculated activities of Hg and Te along the assessed liquidus were converted to the equilibrium partial pressures (Pug and Pxe2) of Hg(g) and Te2(g) using the relationships:

aHg= P.g/p~

and

(Eq 16)

: (PTez/pO@/2 (Eq 17) a t e

where P~tg and P~e~ are the equilibrium pressures of Hg(g) and Te2(g) over pure Hg(L) and Te(L), respectively, and are given by [81 Tun], [74Mil], and [Hultgren, E]:

logpOg_ 3105 + 3.91 MPa (Eq 18) T

and

5960 l~176 = - T + 3.7253 MPa (Eq 19)

Figures 4 and 5 compare the calculated equilibrium partial pressures of Hg(g) and T%(g) along the liquidus with experimental data, respectively, and the agreement is reasonably good.

~HgTe

The Gibbs energy of formation of ~HgTe was determined by [63Gol], [64Pas], [64Sil], [65Bre], [70Lev2], [89Sha], and [91Bre] from dissociation pressure measurements, by [89Fle] from coulometric titration, and by [69Rat] and [90Nas] by an emf method. [7 IRus] determined the specific heat of ~HgTe from 3 to 300 K. [73Vla] estimated AfH0 for ~HgTe as -35.5 kJ/mol, but no method was described therein. [74Mil] assessed these data and reported AfH0(298) for o~HgTe as -31.8 _+4 kJ/mol, based on the emf data of [69Rat] and ignoring the re- sults of dissociation pressure measurements by other investigators, which reported the AfH0(298) for otHgTe as being between -32.6 and -50.2 kJ/mol. In Cd and Zn cbalcogenides, the Gibbs energies of formation determined from dissociation pressure measurements have been found to be fairly reliable



and consistent with the emf data. Furthermore, using the value assessed by [74Mil], we could not obtain consistency with the phase diagram (and partial pressure) data in phase diagram calculations. Therefore, AfH0(298) was obtained from optimiza- tion of the phase equilibria and other thermodynamic data for the Hg-Te system as:

A~-/(~HgTe, 298) = -36.99 kJ/mol (Eq 20)

which is very concordant with the value o f - 3 6 . 5 kJ/mol [90Nas] and is approximately halfway between the values obtained by emf [69Rat] and average from dissociation pressure measurements - -41 kJ/mol [63Gol, 64Sil, 65Bre, 70Lev2, 89Sha, 91Bre]. S0(298) for otHgTe, based on the Cp data of [71Rus] reported by [74Mil]:

S~ 298) = 113 J/K.mol (Eq 21)

The other data are: 106.7 [69Rat], 92.0 [63Gol], 104.9 [90Nas], and 104.9 J/K - mol [91Bre]. Thus, the S O values agree within experimental errors whereas AfH ~ values do not.

The assessed value of AfH0(298) was used, along with the [(G0(T) - H0(298))/T] functions for otHgTe from [74Mil] and for Hg and Te from [Hultgren, E], to give the Gibbs energy of formation of ~HgTe as:

A,G ~ = -54 478 + 36.721 TJ/mol

for the reaction:

(Eq 22)

Hg(L) + Te(L) ~ r (Eq 23)

The enthalpy of melting of o~HgTe was determined to be 35.6 kJ/mol by [70Lev2], 36.4 kJ/mol by [76Ste], 36.5 kJ/mol by [81Su], and 34 kJ/mol by [86Asa] from the vapor pressure measurements over solid and liquid ~HgTe and the latter one from DTA. The value 36 kJ/mol is accepted in this evaluation.

D i s s o c i a t i o n P r e s s u r e

[63Gol], [64Pas], [64Sil], [65Bre], and [70Lev 1 ] measured the dissociation pressure of otHgTe. [74Mil] assessed these data and suggested the following from [65Bre]:

6071 log p (MPa) = - + 5.5 (Eq 24)

T(K)

Heat of transition of ctHgTe into I]HgTe was found to be 192.8 J/mol by [82Ome].

P r e s s u r e

aHgTe (zinc blende, B3 structure) transforms to [~HgTe (cin- nabar, B9 structure) at high pressures [40Bri, 61Blal, 63Jay, 63Mar, 73Lac, 78Rot, 82Ome, 82Ono, 83Wer]. The aHgTe- to-13HgTe transition pressure at room temperature is between 1.3 and 1.4 GPa [40Bri, 61Blal, 63Jay, 73Loc, 78Rot, 82Oht, 82Ome, 82Ono, 83Wer]. [63Jay], [78Rot], and [82Ome] also determined the aHgTe-to-13HgTe transition pressure as a func-

tion of temperature up to -700 ~ and the melting temperatures of e~HgTe and 13HgTe as a function of pressure. Figure 3 gives the P-T phase diagram for HgTe. The L + aHgTe + [3HgTe triple point is at about 1.2 GPa and 615 ~ [63Jay, 78Rot]. The data of [82Ome] at higher temperatures depart from previous findings, showing a different position of the liquidus. A further increase of pressure at room temperature makes the transformation of lgHgTe into "{HgTe (rock salt prototype) at 8.0 _+ 0.3 GPa [82Oht, 82Ono, 82Tsi, 83Hua, 83Wer, 85Hua, 85Ono] and the yHgTe into 8HgTe (~Sn prototype) at 11.5 + 0.6 GPa [82Oht, 82Ono, 83Hua, 83Wer, 85Hua]. eH- gTe was found to be formed above 28.1 GPa [85Hua]. The allotropic HgTe phases are denoted also by numbers I, II, III, IV, and V, respectively. Electric resistance of subsequent HgTe phases decreases with pressure increase so they get more me- tallic character.

C i t e d R e f e r e n c e s

09Peh G. Pellini, R. Sacerdoti, and C. Aureggi, "Combination of Sele- nium and Tellurium with Mercury," Atti. Accad. Naz. Lincei, 18, 211- 217 (1909). (Equi Diagram; Experimental)

26De j: W.F. deJong, "The Structure of HgSe and HgTe," Z. Kristallogr., 63,466-472 (1926) in German. (Crys Structure; Experimental)

26Har: W. Hartwig, Sitzungber. Preuss. Akad. Wissens., Kl. Math.- Phys., 1 O, 79-80 (1926) in German. (Crys Structure; Experimental)

26Zacl: W. Zachariasen, "The Crystalline Structure of ZnTe, CdTe and HgTe," Norsk Geol. 7ids., 8, 302-306 (1926) in German. (Crys Struc- ture; Experimental)

26Zac2: W.H. Zachariasen, "Crystal Structures of the Tellurides of Be, Zn, Cd, and Hg," Z Phys. Chem., 124, 277-284 (1926) in German. (Crys Structure; Experimental)

40Bri: P.W. Bridgman, "The Compression of 46 Substances to 50000 kg/cm2, ' ' Proc. Am. Acad. Arts Sci., 74, 21-51 (1940). (Pressure; Ex- perimental)

54Zor: U. Zorll, "Lattice Constants of Te, HgTe and HgSe," Z Phys., 138, 167-169 (1954) in German. (Crys Structure; Experimental)

58Car: R.O. Carlson,"Electrical Properties of HgTe," Phys. Rev., Ser. I1, 111,476-478 (1958). (Equi Diagram; Experimental)

59Law: W.D Lawson, S. Nielsen, E.H. Putley, and A.S. Young,"Prepa- ration and Properties of HgTe and Mixed Crystals of HgTe-CdTe," J. Phys. Chem. Solids, 9, 325-329 (1959). (Equi Diagram, Crys Struc- ture; Experimental)

60Rod: M. Rodot and H. Rodot,"Band Structure and Mechanism of Dis- persion in Monocrystals of HgTe and SeHg," Compt. Rend., 250, 1447-1449 (1960) in French. (Equi Diagram; Experimental)

60Usa: P.V. Usachev, A.V. Golubkov, and N.S. Volosatova,"Synthesis of HgSe and HgTe," Zh. Prikl. Khim, 33, 2771-2772 (1960) in Russian; TR: J. AppL Chem. (USSR), 33, 2735-2736 (1960). (Equi Diagram; Experimental)

60Wool: J.C. Woolley andB. Ray,"SolidSolution in AIBVITellurides, '' Phys. Chem. Solids, 13, 151-153 (1960). (Equi Diagram, Crys Struc- ture; Experimental)

60Woo2: J.C. Woolley and B. Ray, "Effects of Solid Solutions ofln2Te 3 with AIIB vI Tellurides," Phys. Chem. Solids, 15, 27-32 (1960). (Equi Diagram, Crys Structure; Experimental)

60Woo3: J.C. Woolley and B. Ray, "Effects of Solid Solution of Ga2Te 3 with AIIB VI TeUurides," Phys. Chem. Solids. 16, 102-106 (1960). (Crys Structure; Experimental)

61Blal: J. Blair and A.C. Smith, "Phase Transition in Mercury Tellu- ride," Phys. Rev. Lett., 7(4), 124-125 (1961). (Equi Diagram; Experi- mental)

61Bia2: J. Blair and R. Newiflaam, "Preparation and Physical Properties of Crystals in the HgTe-CdTe Solid Solution Series," MetalL Soc.



Conf., 12, 393-401 (1961). (Equi Diagram, Crys Structure; Experi- mental)

61Rod: M. Rodot, H. Rodot, and R. Triboulet, "Properties of Hg-Se-Te Solid Solutions," J. Appl. Phys., 32, 2254-2256 (1961). (Crys Struc- ture; Experimental)

62Got: N.A. Goryunova, V.S. Grigoreva, EV. Sharavskii, and L.A. Os- nach, "Solid Solutions in the System lnAs-HgTe," Fizika, Leningrad, Sbor., 7-10 (1962) in Russian; TR: Chem. Abstr., 58, 8723 (1963). (Crys Structure; Experimental)

63Abd: G.B. Abdullaev, Sh. Movlanov, M.G. Shakhtahktinskii, and A.A. Kuliev, "Solubilities of Selenium and Mercury in Solid Tellu- rium and Their Effect on the Electrical Properties of Tellurium," lzv. Akad. Nauk Tadzh. SSR, Otd. Geol.-Khim. Tekh. Nauk, 2,13-22 (1963) in Russian. (Equi Diagram; Experimental)

63Deh R.T. Delves and B. Lewis, "Zinc Blende Type HgTe-MnTe Solid Solutions," Phys. Chem. Solids. 24, 549-556 (1963). (Equi Diagram, Crys Structure; Experimental)

63Go1: P. Goldfinger and M. Jeunehomme, "Mass Spectrometric and Knudsen-Cell Vaporization Studies of Group 2B-6B Compound," Trans. Faraday Soc., 59, 2851-2867 (1963). (Thermo; Experimental)

63Jay: A. Jayaraman, W. Klement, and G.C. Kennedy, "Melting and Po- lymorphic Transitions for Some Group II-V1 Compounds at High Pressures," Phys. Rev., 130(6), 2277-2283 (1963). (Equi Diagram; Experimental)

63Mar: A.N. Mariano and E.P. Warekois, "High Pressure Phases of Some Compounds of Groups II-VI," Science, 142, 672-673 (1963). (Equi Diagram; Experimental)

64Gro: S.D. Gromakov, I.V. Zoroatskaya, Z.M. Latypov, M.A. Chvala, E.A. Eidel'man, L.I. Badygina, and L.N. Zaripova, "Method of Studying the Equilibrium Diagrams of Semiconducting Systems," Zh. Neorg. Khim., 9(10), 2485-2487 (1964) in Russian; TR: Russ. J. lnorg. Chem., 9(10), 1340-1341 (1964). (Equi Diagram; Experimen- tal)

64Kru: E. Krucheanu, D. Nicolaescu, and A. Vanku,"Crystal Growth of Monocrystals of HgTe and HgSe from Gas Phase and their Investiga- tion," Kristallografiya, 9, 537 -540 (1964) in Russian. (Crys Sl~'ucture; Experimental)

64Pas: A.S. Pashinkin, "Calculation of Vapor Pressure in Measurements by the Knudsen Method for Completely Dissociated Compounds," Russ. J. Phys. Chem., 38(11), 1461-1463 (1964). (Thermo; Experi- menial)

64Si!: E.Yu. Silina and M.Kh. Karapet' yants, ''Temperature Variation of the Vapor Pressure of Mercury Telluride," Russ. J. Phys. Chem., 38(11), 1490-1491 (1964). (Thermo, Crys Structure;Experimental)

*65Bre: R.E Brebrick and A.J. Strauss, "Partial Pressures of rig(g) and Tez(g) in Hg-Te System from Optical Densities," J. Phys. Chem. Sol- ids, 26, 989-1002 (I 965). (Equi Diagram, Thenno; Experimental)

65Del: R.T Delves, "Constitutional Supercooling and Two-Liquid Growth of HgTe Alloys," Brit. J. Appl. Phys., 16, 343-351 (1965). (Equi Diagram; Experimental)

65Pri: I. Prigogine and R. Defay, Chemical Thermodynamics, Long- mans Green and Co., London, 410-411 (1965). (Thermo; Theory)

67Ray: B. Ray and P.M. Spencer, "Phase Diagram of the Alloy System HgTe-CdTe," Phys. Status Solidi, 22, 371-372 (1967). (Equi Dia- gram; Experimental)

67Str: A.J. Strauss, quoted as private communication in [82Tun]. (Equi Diagram; Experimental)

68Iva: V.1. lvanov-Omskii, B.T. Kolomiets, L.I. Kleshchinskii, and K. P Smekalova, "X-ray Investigation of HgTe," Fiz. Tverd. Tela, 10. 3106-3109 (1968) in Russian. (Crys Structure; Experimental)

68Lev- T.D. Levitskaya, Zh.M. Zubareva, A.V. Vanyukov, A.N. Kre- stovnikov, V.P. Schastlivyi, and P.S. Kireev, "Effect of Non- stoichiometry on the Electrophysical Characteristics of Mercury Telluride," Zh. Fiz. Khim., 42( 11 ), 2757-2760 (1969) in Russian; TR:

Russ. J. Phys. Chem., 42( 11 ), 1467-1469 (1968). (Equi Diagram; Ex- perimental)

68Sni: L. Sniadower, M. Psoda, and R.R. Galazka, "X-Ray Measure- ments of Lattice Dilatation in HgTe," Phys. Status Solidi, 28, KI21- K 123 (1968). (Crys Structure; Experimental)

68Spe: RM. Spencer and B. Ray, "Phase Diagram of the Alloy System HgTe-lnzTe3," Brit. J. Appl. Phys., Set. 2, 1,299-301 (1968). (Equi Diagram, Crys Smacture; Experimental)

68Van: V.G. Vanyarko, V.R Zlomov, and A.V. Novoselova, '`T-X Phase Diagrams of Systems: PbSe-HgSe and PbTe-HgTe," Vestn. Moskov. Univ., Khim., (6), 108 (1968) in Russian. (Equi Diagram; Experimen- tal)

69Rat: E. Ratajczak and J. Terpilowski, "Thermodynamic Properties of HgTe," Roczn. Chem., 43, 1609-1613 (1969) in Polish. (Thermo; Ex- perimental)

70Levl: T.D. Levitskaya, A.V. Vanyukov, A.N. Krestovnikov, and I.M. Bykhanov, "T-X andp-x Projections of the Phase Diagram of Mercury Telluride," Izv. Akad. Nauk SSSR, NeoN. Mater., 6(5), 849-854 (1970) in Russian; TR: Inorg. Mater., 6(5), 747-751 (1970). (Equi Diagram; Experimental; #)

70Lev2: T.D. Levitskaya, A.V. Vanyukov, A.N. Krestovnikov, and V.P. Bystrov, "Saturated Vapor Pressure of Mercuric Telluride," Izv. Akad. Nauk SSSR, Neorg. Mater., 6(3), 559-560 (1970) in Russian; TR: Inorg. Mater., 6(3), 493-494 (1970). (Thermo; Experimental)

71Ale: B.N. Aleksandrov and O.I. Lomonos, "Solubility of Metals in Solid Hg," Zh. Fiz. Khim., 45, 3003-3006 (1971) in Russian. (Eqni Diagram; Experimental)

71Dzi: E.Z. Dziuba, '`The Liquidus Curve and Crystal Growth in the Hg:Te System," J. CO,st. Growth, 8, 221-222 (1971). (Equi Diagram; Experimental)

71Paj: A. Pajaczkowska and E.Z. Dziuba, "The Solubility of rigS, HgSe and HgTe in Hg," J. Cryst. Growth, 11,21-24 (1971). (Equi Diagram; Experimental)

71Rus: A.P. Rusakov, Yr.Kh. Vekilov, and A.E. Kadyshevich, "Specific Heats of CdTe and HgTe and Their Vibrational Frequency Spectra," Fiz. Tverd. Tela, 12(11), 3238-3243 (1970) in Russian; TR: Sov. Phys. Solid State, 12 (11), 2618-2621 (1971). (Thermo; Experimental)

73Lac: A. Lacam, J. Peyronneau, L.J. Engel, and B.A. Lombos, "Pres- sure-Induced Phase Transition in Hg Chalcogenides," Chem. Phys. Lett., 18, 129-131 (1973). (pressure; Experimental)

73Via: N.V. Vladimirov, G.A. Kuzmina, A.A. Ryazantsev, V.A. Khabarova, and E.I. Khabarov, "On Question of Regularity of HgTe- CdTe System," Semiconductors with Narrow Prohibited Zone, Lvov, 69-72 (1973) in Russian. (Equi Diagram, Thermo; Experimental)

74Mi1: K.C. Mills, Thermodynamic Data for Inorganic Sulphides, Se- lenides and Tellurides, Butterworths, London (1974). (Thermo; Re- view)

*76Ste: J. Steininger, "Hg-Cd-Te Phase Diagram Determination by High Pressure Reflux," J. Electron. Mater. 5, 299-320 (1976). (Equi Diagram, Thermo; Experimental)

77Van- A.V. Vanyukov, 1.I. Krotov, andA.l. Ermakov,"Determination of Solubility of CdTe and Solid Solutions CdaHgl_aTe in Hg," Izv. Akad. Nauk SSSR, Neorg. Mater., 13, 815-819 (1977) in Russian. (Equi Dia- gram; Experimental)

78Rot" Yu.M. Rotner, A.V. Suranov, and Yu.V. Vorona, "Constitution Diagram of CdTe-HgTe System at High Pressures," Influence of High Pressure on Substances, Naukovaya Dumka, Kiev, 72-75 (1978) in Russian. (Pressure; Experimental; #)

79Bab: M.B. Babanly, A.A. Kurbanov, and A.A. Kuliev, "Systems HgTe-Sb2Te 3 and HgTe-Bi2Te3," Zh. Neorg. Khim., 24, 2293-2294 (1979) in Russian. (Equi Diagram; Experimental)

79Sha: R.C. Shanna and Y.A. Chang, "Thermodynamics of Metal-Sul- fur Systems III, Thermodynamic Analysis of Liquid Phase and Phase Equilibria in Fe-S System," Metull. Trans. B., 10, 103-108 (1979). (Thermo; Theory)



*80Har: T.C. Harman, "Liquidus Isotherms, Solidus Lines and LPE Growth in the Te-Rich Corner of the Hg-Cd-Te System," J. Electron. Mater, 9, 945-961 (1980). (Equi Diagram; Experimental)

81Su: C.-H. Su, P.-K. Liao, T. Tung, and R.E Brebrick, "Enthalpy of Fu- sion and Thermodynamic Properties of HgTe(s,1)," High Temp. Sci., 14, 181-195 (1981 ). (l'hermo; Experimental)

81Szo: ER. Szofran and S.L. Lehoczky, "The Pseudobinary HgTe-CdTe Phase Diagram," J. Electron. Mater, 10, 1131-1150 (1981). (Equi Diagram; Experimental; #)

*81Tun: T. Tung, L. Golonka, and R.E Brebrick, "Thermodynamic Analysis of the HgTe-CdTe-Te System Using the Simplified RAS Model," J. Electrochem. Soc., 128, 1601-1612 (1981). (Equi Dia- gram, Thermo;Theory;#)

82Gla: V.P. Gladyshev, S.V. Kovaleva, and L.S. Sarieva, "Studies of the BehaviourofElements, Slightly Soluble in Hg, by AC Polarography," Zh. Anal. Khim., 37, 1762-1766 (1982) in Russian. (F_ziui Diagram; Experimental)

82Keh J.D. Kelley, B.G. Martin, ER. Szofran, and S.L. Lehoczky, "Ap- plication of the Regular Associated Solution Model to the Cd-Te and Hg-Te Binary Systems," J. Electrochem. Soc., 129(10), 2360-2365 (1982). (Equi Diagram; Theory; #)

82Kikl: R. Kikuchi, "Liquidus Calculation of II-VI Compound Semi- conductors," Calphad, 6(1), l - 10 (1982). (Equi Diagram; Theory)

82Kik2: R. Kikuchi, '`Theoretical Calculation of Hg-Cd-Te Liquidus- Solidus Phase Diagram," J. Vac. Sci. Technol., 21 (1), 129-132 (1982). (Equi Diagram; Theory; #)

82Oht: A. Ohtani, T. Seike, M. Motobayashi, and A. Onodera, "Electric Properties of HgTe and HgSe under Very High Pressure," Phys. Chem. Solids, 43,627-632 (1982). (Pressure; Experimental)

82Ome: A.V. Omelchenko and V.1. Soshnikov, "On Phase Diagram HgTe," lzu. Akad. Nauk SSSR, Neorg. Mater., 18, 685-686 (1982). (Thermo, Pressure; Experimental; #)

82Ono: A. Onodera, A. Ohtani, M. Motobayashi, T. Seike, O. Shi- nomura, and O. Fukunaga, Proc. of the 8th AIRAPT Conf., CM. Backman, T. Johannisson, and L. Tegner, Ed., Arkitektkopia, Uppsala, Vol. I. 321-326 (1982). (Crys Structure, Pressure; Experimental)

82Tsi: I.M. Tsidilkovskii, V.v. Shchennikov,, and N.G. Gluzman, "Me- tallic Conductivity of Hg Chalcogenides under Superhigh Pressure," Fiz. Tverd. Tela, 24 2658-2662 (1982) in Russian. (pressure; Experi- mental)

82Tun: T. Tung, C. Su,P. Liao, and R.E Brebrick, -Measurement and Analysis of the Phase Diagram and Thermodynamic Properties in the Hg-Cd-Te System," J. Vac. Sci. Technol., 21(1), 117-124 (1982). (Equi Diagram; Theory)

82Wih D.J. Williams, "Eutectic Microstructures in the Cd-Hg-Te Sys- tem," J. Crystal Growth, 58,657-660 (1982). (Equi Diagram; Experi- mental)

83Gav: N.R Gavalenko, N.P. Gorley, S.Yu. Paranchich, V.M. Frasun- yak, and V.V. Khomyak, "Phase Diagrams of Quasibinary Systems CdSe-HgSe, ZnSe-HgSe, MgTe-HgTe," Izv. Akad. Nauk SSSR, Neorg. Mater., 19, 327-329 (1983) in Russian. (Equi Diagram; Ex- perimental)

83Hua: T. Huang and A.L. Ruoff, "Pressure-Induced Phase Transitions of HgTe," Phys. Status Solidi, A, 77, K 193-K 197 (1983). (Crys Struc- ture, Pressure; Experimental)

83Ven: RE Vengel, V.N. Tomashik, and l.P Mizetskaya, "Physico- Chemical Reactions in the HgTe-SnTe System," Ukr. Khim. Zh., 49, 1247-1250 (1983 ). (Equi Diagram; Experimental)

83Wer: A. Werner, H.D. Hochheimer, K. Strrssner, and A. Jayaraman, "High Pressure X-ray Diffraction Studies on HgTe and HgS to 20 GPa," Phys. Rev., B, 28, 3330-3334 (1983). (Crys Structure, Pressure; Experimental)

84Her: RE. Heming, "Experimental Determination of the Hg-Rich Cor- ner of the Hg-Cd-Te Phase Diagram," J. Electron Mater., 13, 1-14 (1984), (Equi Diagram; Experimental)

85Asa: MM. Asadov. "Departure from Stoichiometry in Hg Chalco- genides," lzv. Akad. Nauk SSSR, Neorg. Mater., 21,324-326 (1985) in Russian. (Equi Diagram; Experimental)

*85Hua: T.-L. Huang and A.L. Ruoff, "High Pressure Induced Phase Transitions of Mercury Chalcogenides," Phys. Rev. B, 31,5976-5983 (1983). (Crys Structure, Pressure; Experimental)

85Ono: A. Onodera, A. Ohtani, T. Seike, M. Motobayashi, O. Shimoura, and H. Kawamura, "Physical Properties of some Chaicogenides under Pressure," Solid State Physics under Pressure, S. Minomura, Ed., Terra Scientific Publishing, Tokyo, 141-144 (1985). (Pressure; Ex- perimental)

86Asa: M.M. Asadov, "Heat of Fusion of Mercury Chalcogenides,"Az- erb. Khim. Zh., (2), 101-103 (1986) in Russian. (Equi Diagram, Thermo; Experimental)

86Bri: J.C. Brice, P. Capper, and C.L. Jones, '`The Phase Diagram of the Pseudobinary System: CdTe-HgTe and the Segregation of CdTe," J. Cryst. Growth, 75, 395-399 (1986). (Equi Diagram; Experimental)

86Gum: C. Guminski and Z. Galus, "Te in Hg," Metals in Mercury, Solu- bility Data Series, C. Hirayama, Ed., Pergamon, Oxford, 25, 194-205 (1986). (Equi Diagram; Review)

86Leu: Y. Leute and H.-J. KOller,"The Quasibinary Phase Diagrams of the Quasiternary System (Hg, Pb) (Se, Te)," Z Phys. Chem., N.E, 149, 213-217 (1986). (Crys Structure; Experimental).

88Bre: R.E Brebrick, "Thermodynamic Modeling of the Hg-Cd-Te and Hg-Zn-Te Systems," J. Cryst. Growth, 86, 39-48 (1988). (Thermo; Theory; #)

89Fie: J.G. Fleming and D.A. Stevenson, "The Determination of the Free Energy of Formation of Binary Tellurides Using Li Coulometric Titration Techniques," J. Electrochem. Soc., 136, 3859-3863 (1989). (Thermo; Experimental)

89Sha: Y.G. Sha, K.T. Cheng, R. Fang, and R.E Brebrick, "Gibbs Free Energy of Formation and Partial Pressure of Hg over Te Saturated HgTe (c) between 385 and 724 K," J. Electrochem. Soc., 136, 3837- 3841 (1989). (Thermo; Experimental)

*90Nas: A. Nasar and M. Shamsuddin, '`Thermodynamic Investigation of HgTe," J. Less-Common Met., 161, 87-92 (1990). (Crys Structure, Thermo; Experimental)

91Bre: R,E Brebrick, K.-T. Chen, H.-C. Liu, R. Fang, and T.-C. Yu, "Thermodynamic Properties of HgTe-CdTe Solid Solutions," High Temp. Sci., 31, 181-207 (1991). (Crys Structure, Thermo; Experimen- tal)

93And: A.M. Andrukhiv, A.M. Litvak, and K.E. Mironov, "Phase Equilibria in the Hg-Zn-Hg System and Elastic Stress During Epi- taxial Crystallization," Neorg. Mater, 29 (4), 492-498 (1993) in Rus- sian. (Equi Diagram; Theory)

*Indicates key paper. #Indicates presence of a phase diagram.

Hg-Te evaluation contributed by R.C. Sharma and Y.A. Chang, Department of Metallurgical and Mineral Engineering, University of Wisconsin-Madison, 1509 University Ave., Madison, W153706, and C. Guminski, University of Warsaw, Pasteura 1, 02093 Warsaw, Poland. Professor Sharma was a Visiting Assistant Professor from 1984 to 1986 on leave from the Indian Institute of Technology, Kanpur, U.P. 208016 India. This work was supported by ASM International. Litera- ture searched through 1993. Professor Chang is the Alloy Phase Diagram Program Category Editor for selected binary Group II-V1 and III-V alloys, and Dr. Gu- minski is the Alloy Phase Diagram Program Category Editor for binary mercury alloys.


The Hg-Te (mercury-tellurium) system

Documents

Transcript of The Hg-Te (mercury-tellurium) system