Simulations of Carbon Nanotubes
in Strength Characterization,
Molecular Electronic Components
and Molecular Motors
Computational
Nanotechnology Group
This is an abstract
for a talk to be given at the
Fifth
Foresight Conference on Molecular Nanotechnology.
There will be a link from here to the full article when it is
available on the web.
Large scale classical molecular dynamics, employing Brenner's
potential, and quantum generalized tight-binding molecular
dynamics methods have been used in simulations of strength and
electronic characterization of single and multiwalled carbon
nanotubes and their junctions. Carbon nanotubes are expected to
play significant role in the design and operation of many
nano-mechanical and nano-electronic devices of future. In the
simulations of carbon nanotubes under compressive and bending
strains, we find that inclusion of long range non-bonding
interactions helps in strain energy relaxation/redistribution
along the length of a single-walled tube and adds towards the
stifness of the multiwalled tube against the formation of
localized kinks or defects. Straight, small, and large-angle
hetero-junctions of carbon nanotubes of different windings are
created and relaxed through a generalized tight-binding molecular
dynamics method. We analyze the stability and local density of
states of the created 2-, 3- and 4-point junctions, and discuss
their use in a molecular network that could be bullwark of future
molecular electronic devices.
Finally, the rotational dynamics of a carbon nanotube laser
motor is explored through classical molecular dynamics
simulations. The molecular gear motors are constructed by
attaching benzyne molecular teeth in the body of a carbon
nanotubes, and the motors are powered by external laser fields.
We show that when the laser frequency is tuned close to the
intrinsic frequency of the carbon nanotube motor, stable
unidirectional rotations of the gear motor with both cw and
pulsed laser fields are possible. The performance with a pulsed
laser field is better as compared to a cw laser field, because
frictional heat generated in the former case is much less than
the heat generated in the latter.
*Corresponding Address:
Deepak Srivastava, Computational Nanotechnology Group
NASA Ames Research Center, Mail Stop T27A-1
Moffett Field, CA 94035-1000
telephone: (650) 604-3486
email: [email protected]
Web: http://science.nas.nasa.gov/~deepak/home.html
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