Assessing the driving force of a structural distortion by the simulated evolution of the local density of states

Abstract

In this paper we show that the driving force leading to the metal-semiconductor structural phase transition occurring in epitaxial ${\mathrm{FeSi}}_{2}$ with film thickness, originates from a local Jahn-Teller distortion. This effect can be straightforwardly seen by the analysis of the site-projected density of states during a variable cell molecular dynamics for the bulk configuration. We point out that the evolution of the local density of states is a reliable and powerful tool solely provided by tight-binding molecular dynamics.