Thermodynamics of supercooled liquids in the inherent structure formalism: a case study

TL;DR

This paper reviews the thermodynamics of supercooled liquids using the inherent structure formalism and presents calculations for a binary Lennard-Jones mixture, providing insights into the energy landscape and thermodynamic behavior near the mode-coupling temperature.

Contribution

It introduces a detailed analysis of the potential energy landscape of supercooled liquids and evaluates the inherent structure formalism against numerical data for a binary Lennard-Jones system.

Findings

The distribution of basins varies with temperature.

The degeneracy of inherent structures can be quantified.

The partition function near the mode-coupling temperature is well approximated by a product of two factors.

Abstract

In this article we review the thermodynamics of liquids in the framework of the inherent structure formalism. We then present calculations of the distribution of the basins in the potential energy of a binary Lennard-Jones mixture as a function of temperature. The comparison between the numerical data and the theoretical formalism allows us to evaluate the degeneracy of the inherent structures in a bulk system and to estimate the energy of the lowest energy disordered state (the Kauzmann energy). We find that, around the mode-coupling temperature, the partition function of the liquid is approximated well by the product of two loosely coupled partition functions, one depending on the inherent structures quantities (depth of the basins and their degeneracy) and one describing the free energy of the liquid constrained in one typical basin.