Electronic structure of amorphous germanium disulfide via density functional molecular dynamics simulations

TL;DR

This study uses density functional molecular dynamics to analyze the electronic structure of amorphous germanium disulfide, revealing detailed electronic properties, bond nature, and charge distribution influenced by the amorphous structure.

Contribution

First application of density functional molecular dynamics to explore the electronic structure and charge distribution in amorphous g-GeS₂.

Findings

Electronic density of states matches XPS data

Identification of covalent bond nature in different environments

Observation of locally charged zones due to amorphous disorder

Abstract

Using density functional molecular dynamics simulations we study the electronic properties of glassy g-GeS$_2$. We compute the electronic density of states, which compares very well with XPS measurements, as well as the partial EDOS and the inverse participation ratio. We show the electronic contour plots corresponding to different structural environments, in order to determine the nature of the covalent bonds between the atoms. We finally study the local atomic charges, and analyze the impact of the local environment on the charge transfers between the atoms. The broken chemical order inherent to amorphous systems leads to locally charged zones when integrating the atomic charges up to nearest-neighbor distances.