Strong geometric frustration in model glassformers

TL;DR

This paper investigates local structures in three model glassformers, revealing that despite similar local arrangements, a decoupling between structural and dynamic lengthscales suggests strong geometric frustration inhibits structural lengthscale growth.

Contribution

It introduces a comparative analysis of local structures in different glassformers and links the lack of structural lengthscale growth to geometric frustration.

Findings

Local structures form percolating networks in all models

Strong decoupling between structural and dynamic lengthscales observed

Lack of structural lengthscale growth may be due to geometric frustration

Abstract

We consider three popular model glassformers, the Kob-Andersen and Wahnstr\"om binary Lennard-Jones models and weakly polydisperse hard spheres. Although these systems exhibit a range of fragilities, all feature a rather similar behaviour in their local structure approaching dynamic arrest. In particular we use the dynamic topological cluster classification to extract a locally favoured structure which is particular to each system. These structures form percolating networks, however in all cases there is a strong decoupling between structural and dynamic lengthscales. We suggest that the lack of growth of the structural lengthscale may be related to strong geometric frustration.