Structure of the Lennard-Jones liquid estimated from a single simulation

TL;DR

This paper presents a method combining recent theoretical approaches to determine the structure of Lennard-Jones liquids at various state points from a single simulation, leveraging isomorph theory and van't Hoff's assumption.

Contribution

It introduces a novel approach to predict liquid structures at different conditions from one simulation, applicable to hidden scale-invariant systems.

Findings

The structure can be estimated at arbitrary state points along an isochore.

Two temperature ranges validate van't Hoff's assumption for LJ liquids.

The method applies broadly to systems obeying scale invariance and van't Hoff's assumption.

Abstract

Combining the recent Piskulich-Thompson approach [Z. A. Piskulich and W. H. Thompson, {\it J. Chem. Phys.} {\bf 152}, 011102 (2020)] with isomorph theory, from a single simulation, the structure of a single-component Lennard-Jones (LJ) system is obtained at an arbitrary state point in almost the whole liquid region of the temperature-density phase diagram. The LJ system exhibits two temperature range where the van't Hoff's assumption that energetic and entropic forces are temperature independent is valid. A method to evaluate the structure at an arbitrary state point along an isochore from the knowledge of structures at two temperatures on the isochore is also discussed. We argue that, in general, the structure of any hidden scale-invariant system obeying the van't Hoff's assumption in the whole range of temperatures can be determined in the whole liquid region of the phase diagram from only a single simulation.