Molecular Nanotechnologywww.zyvex.com/nano

Ralph C. MerklePrincipal Fellow, Zyvex

www.merkle.com

Nick Smith, ChairmanHouse Subcommittee on Basic Research

June 22, 1999

In Fiscal Year 1999, the federal government will spend approximately $230 million on nanotechnology research.

National Nanotechnology Initiative

Announced by Clinton at Caltech Interagency (AFOSR, ARO, BMDO, DARPA,

DOC, DOE, NASA, NIH, NIST, NSF, ONR, and NRL)

FY 2001: $497 million

http://www.whitehouse.gov/WH/New/html/20000121_4.html

Academic and Industry

Caltech’s MSC (1999 Feynman Prize), Rice CNST (Smalley), USC Lab for Molecular Robotics, etc

Private nonprofit (Foresight, IMM) Private for profit (IBM, Zyvex) And many more….

There is a growing sense in the

scientific and technical community that we are about to enter a golden new era.

Richard Smalley

1996 Nobel Prize, Chemistry

http://www.house.gov/science/smalley_062299.htm

The principles of physics, as far as I can see, do not speak against the possibility of maneuvering things atom by atom.It is not an attempt to violate any laws; it is something, in principle, that can be done; but in practice, it has not been done because we are too big.

Richard Feynman, 1959

http://www.zyvex.com/nanotech/feynman.html

The book that laid out the technical argument for molecular nanotechnology:

Nanosystemsby K. Eric Drexler, Wiley 1992

Three historical trendsin manufacturing

More flexible More precise Less expensive

The limit of these trends: nanotechnology

Fabricate most structures consistent with physical law

Get essentially every atom in the right place

Inexpensive (~10-50 cents/kilogram)

http://www.zyvex.com/nano

Coal Sand Dirt, water

and air

Diamonds Computer chips Grass

It matters how atomsare arranged

Today’s manufacturing methods move atoms in

statistical herds Casting Grinding Welding Sintering Lithography

Possible arrangements of

atoms.

What we can make today(not to scale)

The goal: a healthy bite.

.

Core molecularmanufacturingcapabilities

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Overview of the development of molecular nanotechnology

Terminological caution

“Nanotechnology” has been applied to almost any research where some dimension is less than a micron (1,000 nanometers) in size.

Example: sub-micron optical lithography

Two morefundamental ideas

Self replication (for low cost) Positional assembly (so

molecular parts go where we want them to go)

Von Neumann architecture for a self replicating system

UniversalComputer

UniversalConstructor

http://www.zyvex.com/nanotech/vonNeumann.html

Drexler’s architecture for an assembler

Molecularcomputer

Molecularconstructor

Positional device Tip chemistry

Illustration of an assembler

http://www.foresight.org/UTF/Unbound_LBW/chapt_6.html

The theoretical concept of machine duplication is well developed. There are several alternative strategies by which machine self-replication can be carried out in a practical engineering setting.

Advanced Automation for Space MissionsProceedings of the 1980 NASA/ASEE Summer Study

http://www.zyvex.com/nanotech/selfRepNASA.html

A C program that prints out an exact copy of itself

main(){char q=34, n=10,*a="main() {char q=34,n=10,*a=%c%s%c; printf(a,q,a,q,n);}%c";printf(a,q,a,q,n);}

For more information, see the Recursion Theorem:http://www.zyvex.com/nanotech/selfRep.html

English translation:

Print the following statement twice, the second time in quotes:“Print the following statement twice, the second time in quotes:”

C program 800Von Neumann's universal constructor 500,000Internet worm (Robert Morris, Jr., 1988) 500,000Mycoplasma capricolum 1,600,000E. Coli 9,278,442Drexler's assembler 100,000,000Human 6,400,000,000NASA Lunar

Manufacturing Facility over 100,000,000,000http://www.zyvex.com/nanotech/selfRep.html

Complexity of self replicating systems (bits)

How cheap?

Potatoes, lumber, wheat and other agricultural products are examples of products made using a self replicating manufacturing base. Costs of roughly a dollar per pound are common.

Molecular manufacturing will make almost any product for a dollar per pound or less, independent of complexity. (Design costs, licensing costs, etc. not included)

How long?

The scientifically correct answer is: I don’t know

Trends in computer hardware suggest the 2010 to 2020 time frame

Of course, how long it takes depends on what we do

Developmental pathways

Scanning probe microscopy Self assembly Progressively smaller positional

assembly Hybrid approaches

Moving molecules with an SPM(Gimzewski et al.)

http://www.zurich.ibm.com/News/Molecule/

Self assembled DNA octahedron(Seeman)

http://seemanlab4.chem.nyu.edu/nano-oct.html

DNA on an SPM tip(Lee et al.)

http://stm2.nrl.navy.mil/1994scie/1994scie.html

Buckytubes(Tough, well defined)

Buckytube glued to SPM tip(Dai et al.)

http://cnst.rice.edu/TIPS_rev.htm

Building the tools to build the tools

Directly manufacturing a diamondoid assembler using existing techniques appears very difficult .

We’ll have to build intermediate systems able to build better systems able to build diamondoid assemblers.

If we can make whatever we want

what do we want to make?

Diamond Physical PropertiesProperty Diamond’s value Comments

Chemical reactivity Extremely lowHardness (kg/mm2) 9000 CBN: 4500 SiC: 4000Thermal conductivity (W/cm-K) 20 Ag: 4.3 Cu: 4.0Tensile strength (pascals) 3.5 x 109 (natural) 1011 (theoretical)Compressive strength (pascals) 1011 (natural) 5 x 1011

(theoretical)Band gap (ev) 5.5 Si: 1.1 GaAs: 1.4Resistivity (W-cm) 1016 (natural)Density (gm/cm3) 3.51Thermal Expansion Coeff (K-1) 0.8 x 10-6 SiO2: 0.5 x 10-6Refractive index 2.41 @ 590 nm Glass: 1.4 - 1.8Coeff. of Friction 0.05 (dry) Teflon: 0.05

Source: Crystallume

Strength of diamond

Diamond has a strength-to-weight ratio over 50 times that of steel or aluminium alloy

Structural (load bearing) mass can be reduced by about this factor

When combined with reduced cost, this will have a major impact on aerospace applications

A hydrocarbon bearing

http://www.zyvex.com/nanotech/bearingProof.html

Neon pump

A planetary gear

http://www.zyvex.com/nanotech/gearAndCasing.html

A proposal for a molecular positional device

Classical uncertainty

kTkb2

σ: mean positional error k: restoring forcekb: Boltzmann’s constantT: temperature

A numerical example of classical uncertainty

kTkb2

σ: 0.02 nm (0.2 Å) k: 10 N/mkb: 1.38 x 10-23 J/KT: 300 K

Born-Oppenheimer approximation

A carbon nucleus is more than 20,000 times as massive as an electron, so it will move much more slowly

Assume the atoms (nuclei) are fixed and unmoving, and then compute the electronic wave function

If the positions of the atoms are given by r1, r2, .... rN then the energy of the system is: E(r1, r2, .... rN)

This is fundamental to molecular mechanics

Quantum positional uncertainty in the ground state

σ2: positional variance k: restoring forcem: mass of particleħ: Planck’s constant divided by 2π

km22

Quantum uncertainty in position

C-C spring constant: k~440 N/m Typical C-C bond length: 0.154

nm σ for C in single C-C bond: 0.004 nm σ for electron (same k): 0.051

nm

Molecular mechanics

Nuclei are point masses Electrons are in the ground state The energy of the system is fully

determined by the nuclear positions Directly approximate the energy from the

nuclear positions, and we don’t even have to compute the electronic structure

Example: H2

Internuclear distance

En

erg

y

Molecular mechanics

Internuclear distance for bonds Angle (as in H2O)

Torsion (rotation about a bond, C2H6

Internuclear distance for van der Waals Spring constants for all of the above More terms used in many models Quite accurate in domain of

parameterization

Molecular tools

Today, we make things at the molecular scale by stirring together molecular parts and cleverly arranging things so they spontaneously go somewhere useful.

In the future, we’ll have molecular “hands” that will let us put molecular parts exactly where we want them, vastly increasing the range of molecular structures that we can build.

Synthesis of diamond today:diamond CVD

Carbon: methane (ethane, acetylene...)

Hydrogen: H2

Add energy, producing CH3, H, etc.

Growth of a diamond film.

The right chemistry, but little control over the site of reactions or exactly what is synthesized.

A hydrogen abstraction tool

http://www.zyvex.com/nanotech/Habs/Habs.html

Some other molecular tools

A synthetic strategy for the synthesis of diamondoid structures

Positional assembly (6 degrees of freedom)

Highly reactive compounds (radicals, carbenes, etc)

Inert environment (vacuum, noble gas) to eliminate side reactions

The impact of nanotechnologydepends on what’s being

made Computers, memory, displays Space Exploration Medicine Military Environment, Energy, etc.

Powerful computers

In the future we’ll pack more computing power into a sugar cube than the sum total of all the computer power that exists in the world today

We’ll be able to store more than 1021 bits in the same volume

Or more than a billion Pentiums operating in parallel

Powerful enough to run Windows 2015

Memory probe

Displays

Molecular machines smaller than a wavelength of light will let us build holographic displays that reconstruct the entire wave front of a light wave

It will be like looking through a window into another world

Covering walls, ceilings and floor would immerse us in another reality

Space

Launch vehicle structural mass will be reduced by about a factor of 50

Cost per pound for that structural mass will be under a dollar

Which will reduce the cost to low earth orbit by a factor 1,000 or more

http://science.nas.nasa.gov/Groups/Nanotechnology/publications/1997/

applications/

It costs less to launch less

Light weight computers and sensors will reduce total payload mass for the same functionality

Recycling of waste will reduce payload mass, particularly for long flights and permanent facilities (space stations, colonies)

Swallowing the surgeon

...it would be interesting in surgery if you could swallow the surgeon. You put the mechanical surgeon inside the blood vessel and it goes into the heart and “looks” around. ... Other small machines might be permanently incorporated in the body to assist some inadequately-functioning organ.

Richard P. Feynman, 1959 Nobel Prize for Physics, 1965

Nanomedicine Volume I

By Robert Freitas Surveys medical applications of

nanotechnology Extensive technical analysis Volume I (of three) published in 1999 http://www.foresight.org/Nanomedicine

Mitochondrion

20 nm scale bar Ribosom

e

Molecular computer(4-bit) +

peripherals

Molecular bearing

“Typical” cell

Mitochondrion

Molecular computer + peripherals

Disease and illness are caused largely by damage at the molecular and cellular level

Today’s surgical tools are huge

and imprecise in comparison

http://www.foresight.org/Nanomedicine

In the future, we will have fleets of surgical tools that are molecular both in size and precision.

We will also have computers that are much smaller than a single cell with which to guide these tools.

Medical applications

Killing cancer cells, bacteria Removing blockages Providing oxygen (artificial red

blood cell) Adjusting other metabolites

A revolution in medicine

Today, loss of cell function results in cellular deterioration:

function must be preserved With medical nanodevices, passive structures

can be repaired. Cell function can be restored provided cell structure can be inferred:

structure must be preserved

Cryonics37º C 37º C

-196º C (77 Kelvins)

Freeze Restoreto health

Time

Tem

pera

ture

(many decades)

Clinical trialsto evaluate cryonics

Select N subjects Freeze them Wait 100 years See if the medical technology of 2100 can

indeed revive them

But what do we tell those who don’t expect to live long enough to see the results?

Would you rather join:The control group?

(no action required)

orThe experimental group?

(see www.alcor.org for info)

Military applications of molecular manufacturing have even greater potential than nuclear weapons to radically change the balance of power.

Admiral David E. Jeremiah, USN (Ret)Former Vice Chairman, Joint Chiefs of StaffNovember 9, 1995

http://www.zyvex.com/nanotech/nano4/jeremiahPaper.html

Human impact on the environment depends on

Population Living standards Technology

Restoring the environment with nanotechnology

Low cost greenhouse agriculture Low cost solar power Pollution free manufacturing The ultimate in recycling

Solar power and nanotechnology

The sunshine reaching the earth has almost 40,000 times more power than total world usage.

Nanotechnology will produce efficient, rugged solar cells and batteries at low cost.

Power costs will drop dramatically

Environmentally friendly manufacturing

Today’s manufacturing plants pollute because they use imprecise methods.

Nanotechnology is precise — it will produce only what it has been designed to produce.

An abundant source of carbon is the excess CO2 in the air

Nanotechnology offers ... possibilities for health, wealth, and capabilities beyond most past imaginings.

K. Eric Drexler

The best wayto predict the future

is to invent it.

Alan Kay