Distributions of pore sizes and atomic densities in binary glasses revealed by molecular dynamics simulations

TL;DR

This study uses molecular dynamics simulations to analyze pore size distributions and atomic densities in binary glasses formed by rapid quenching, revealing how these properties depend on temperature and density.

Contribution

It introduces a scaling relation for pore-size distributions and characterizes the broad distribution of local densities in glassy materials.

Findings

Pore-size distributions follow a robust scaling relation at high porosity.

Local density distributions are broad and shift with increasing average density.

Transition to vitreous state involves spinodal decomposition and solidification.

Abstract

We report on the results of a molecular dynamics simulation study of binodal glassy systems, formed in the process of isochoric rapid quenching from a high-temperature fluid phase. The transition to vitreous state occurs due to concurrent spinodal decomposition and solidification of the matter. The study is focused on topographies of the porous solid structures and their dependence on temperature and average density. To quantify the pore-size distributions, we put forth a scaling relation that provides a robust data collapse in systems with high porosity. We also find that the local density of glassy phases is broadly distributed, and, with increasing average glass density, a distinct peak in the local density distribution is displaced toward higher values.