New optimization scheme to obtain interaction potentials for oxide glasses

TL;DR

This paper introduces a novel optimization scheme for deriving effective pair potentials for oxide glasses, utilizing ab-initio and experimental data to improve accuracy over previous models.

Contribution

The paper presents a new parameterization method that yields more accurate pair potentials for oxide glasses using a combination of simulation and experimental data.

Findings

New potentials outperform previous models in accuracy

Good agreement with experimental pressure dependence of elastic moduli

Simple two-body potentials can surpass complex three-body ones

Abstract

We propose a new scheme to parameterize effective potentials that can be used to simulate atomic systems such as oxide glasses. As input data for the optimization, we use the radial distribution functions of the liquid and the vibrational density of state of the glass, both obtained from ab-initio simulations, as well as experimental data on the pressure dependence of the density of the glass. For the case of silica, we find that this new scheme facilitates finding pair potentials that are significantly more accurate than previous ones even if the functional form is the same, thus demonstrating that even simple two-body potentials can be superior to more complex three-body potentials. We have tested the new potential by calculating the pressure dependence of the elastic moduli and find a good agreement with the corresponding experimental data.