Structures and Energetics of Si Nanotubes from Molecular Dynamics and Density Functional Theory
Date of this Version5-2008
Phys. Rev. B Vol. 78 (2008) 205315.
A. S. would like to thank A.C.T. van Duin and W.A. Goddard, III for the use of ReaxFF code and P.A. Schultz for help with SeqQuest. This work was partially supported by the Semiconductor Research Corporation, by the Microelectronics Advanced Research Corporation and its Focus Center on Materials, Structures and Devices, by the Network for Computational Nanotechnology through nnoHUB.org computational resources funded by the US National Science Foundation grant no. EEC-0228390, and by Purdue University
This document has been peer-reviewed.
We use molecular dynamics (MD) with a first principles-based force field (ReaxFF) and density functional theory (DFT) to predict the atomic structure, energetics and elastic propoerties of Si nanotubes. We find various low-energy and low-symmetry hollow structures with external diameters of about 1 nm. These are the most stable structures in this small-diameter regime reported so far and exhibit properties very different from the bulk. While the cohesive energies of the four most stable nanotubes reported here are similar (from 0.638 to 0.697 eV above bulk Si), they have disparate Young's moduli (from 72 to 123 GPa).
molecular dynamics, density functional theory
Nanoscience and Nanotechnology