<b>Characterization of nanocrystalline silicon germanium film and nanotube in adsorption gas by Monte Carlo and Langevin dynamic simulation</b>

Abstract

The nanocrystalline silicon-germanium films (Si/Ge) and Si/Ge nanotubes have low band gaps and high carrier mobility, thus offering appealing potential for absorbing gas molecules. Interaction between hydrogen molecules and bare as well as functionalized Si/Ge nanofilm and nanotube was investigated using Monte Carlo (MC) and Langevin dynamic (LD) simulation methods. It was found that the binding energy of the H2 on the Si/Ge surface is weak, and be enhanced by increasing curvature of surface to tube form and increasing temperature. The structural, total energy and energy band gaps of H2 absorbed nanocrystalline silicon germanium film (Si/Ge) and as it passes through Si/Ge nanotube was also studied. They are computed with MC and LD simulation the methods at different temperatures. All the calculations were carried out using HyperChem 7.0 program package. KEY WORDS: Monte Carlo, Langevin dynamic simulation, Silicon-germanium films (Si/Ge), Si/Ge nanotube  Bull. Chem. Soc. Ethiop. 2008, 22(2), 277-286.