First principles molecular dynamics simulations of pressure-induced structural transformations in silicon clusters

摘要

Using a recently developed constant pressure ab initio molecular dynamics method for studying nonperiodic systems, we have investigated pressure-induced structural transformations in silicon clusters. Pressure is applied and tuned through a liquid described by a classical potential, while the clusters are treated within a density functional theory scheme. Pressure-induced transformations in the Si_35H_36 and Si_71H_60 clusters show common characteristics, with a tendency toward metallicity at high pressure and a hysrteretic behavior when the pressure is released.