An operational scheme to determine the locally preferred structure of model liquids

TL;DR

This paper introduces a systematic operational method to identify the locally preferred structure in model liquids by finding the global energy minimum of atom clusters in a liquid-like environment, aiding understanding of supercooling and glass formation.

Contribution

It presents a new approach to determine the locally preferred structure using an external potential, improving upon previous methods and applied to Lennard-Jones liquids.

Findings

The method successfully identifies icosahedral structure as the locally preferred configuration.

It improves the systematic determination of local structures in model liquids.

The approach is validated on Lennard-Jones liquids without prior assumptions.

Abstract

We present an operational method to determine the 'locally preferred structure'' of model liquids, a notion often put forward to explain supercooling of a liquid and glass formation. The method relies on finding the global minimum in the (free) energy landscape of clusters of atoms or molecules embedded in a liquid-like environment. We propose a more systematic approach of the external potential mimicking the influence of the surrounding bulk liquid on the cluster than in our previous work [S. Mossa and G. Tarjus, J. Chem. Phys 119, 8069 (2003)]. The procedure is tested on the one-component Lennard-Jones liquid and we recover, without a priori input, that the locally preferred structure is an icosahedral arrangement of thirteen atoms.