Atomic-charge distribution in glasses by terahertz spectroscopy

TL;DR

This paper introduces a method using terahertz spectroscopy to determine atomic-charge distribution widths in glasses, supported by theoretical modeling, providing new insights into the charge distribution in As2S3 glass.

Contribution

It presents a novel experimental approach combined with theoretical modeling to quantify atomic-charge distribution in glasses.

Findings

Charge distribution width for As2S3 glass is 0.12 (e).

Terahertz spectroscopy effectively probes atomic-charge distributions.

Theoretical model qualitatively supports experimental results.

Abstract

It is demonstrated that the width of the uncorrelated atomic-charge distribution in glasses can be extracted from the frequency dependence of the coupling coefficient for the far-infrared absorption measured experimentally by the time-domain terahertz spectroscopy technique. This value for As2S3 glass is found to be 0.12 (e). A density functional theory-based tight-binding molecular dynamics model of As2S3 glass qualitatively supports these findings.