Local Deformation at the Crossing of Carbon Nanotubes

When two carbon nanotubes cross, they both deform from circular cross sections. This changes their local electronic structure and alters the electrical resistance of the junction. To understand the electrical properties of nanotube-nanotube contacts, we have used the CNF computing cluster to perform molecular mechanics simulations of nanotube crossings, with up to 120,000 atoms in the simulations. The calculations are in good agreement with atomic-force microscope measurements of tube deformations.

Z. Wang, LCRE/DTMN/LITEN, CEA-Grenoble, FranceWork performed at Cornell NanoScale Facility

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Comparison between molecular mechanics simulation and AFM data concerning the difference between the height at the crossing point and the sum of the nanotube apparent heights as a function of the nanotube average apparent height.

Daniel C. Ralph, Cornell University, ECCS - 0335765