Line of critical states for Lennard-Jones fluids

TL;DR

This paper introduces a method to identify the critical temperature in Lennard-Jones fluids using percolation transition loci, supported by extensive MD simulations, challenging the traditional van der Waals critical point concept.

Contribution

It presents a novel approach to determine the critical temperature from within the supercritical phase, emphasizing the existence of a supercritical mesophase and a line of critical states.

Findings

Identification of a supercritical mesophase

Existence of a line of critical states

Refutation of the van der Waals critical point

Abstract

A method of obtaining the critical temperature from within a supercritical mesophase bounded by percolation transition loci is described. We report thermodynamic pressures from MD simulations for more than 2000 state points along 7 near-critical isotherms of a Lennard-Jones fluid. Direct evaluation of Gibbs chemical potential along the critical isotherm reaffirms the existence of a supercritical mesophaseand a line of critical states and non-existence of van der Waals critical point.