"FY2002 Report of ES Results" Large Scale Simulations for Carbon Nanotubes

Carbon nanotubes (CNTs) and fullerenes have a lot of potential applications in nanotechnology. In the stream of efforts to exploit these nanoscale materials, the computational simulations have turned out to be powerful and efficient tools. Especially, as the recent trend in technology made it possible to manipulate a further miniaturized structures, required simulations for emerging material become bigger and bigger. Aiming at realistic simulations for nanomaterials, we have developed a large-scale computation technique utilizing tight-binding molecular dynamic method, ab initio density functional theory (DFT), and time-dependent DFT method. By an efficient optimization on ES, we get the performance of 7.04 Tera flops using 435 nodes for TB calculation for CNT thermal conductivity. We have studies various physical properties of nano-carbon material e.g., the thermal conductivity of the single wall CNT, stability of super-diamond, synthetic diamond, stability of nanotube peapod with a defective wall, and designing of a purification of CNT. During these works, we have realized that the Earth Simulator is very powerful tool for large-scale material simulations.