Modeling Vibrational Behavior of Silicon Nanowires Using Accelerated Molecular Dynamics Simulations

Abstract

The classical methods utilized for modeling nano-scale systems are not practical because of the enlarged surface e ects that appear at small dimensions. Contrarily, implementing more accurate methods is followed by prolonged computations as these methods are highly dependent on quantum and atomistic models, and they can be employed for very small sizes in brief time periods. In order to speed up the Molecular Dynamics (MD) simulations of the silicon structures, Coarse-Graining (CG) models are put forward in this research. The procedure involves establishing a map between the main structure's atoms and the beads comprising the CG model and modifying the parameters of the system so that the original and the CG models can reach identical physical parameters. The accuracy and speed of this model are investigated through various static and dynamic simulations and by assessing the e ect of size. The simulations show that for a nanowire with thickness over 10 a, where parameter a is the lattice constant of diamond structure, Young's modulus obtained by CG and MD models di ers by less than 5 percent. The results also show that the corresponding CG model performs 190 times faster than the AA model.