Critical point and coexistence curve properties of the Lennard-Jones fluid: A finite-size scaling study

Abstract

Monte Carlo simulations within the grand canonical ensemble are used to explore the liquid-vapour coexistence curve and critical point properties of the Lennard-Jones fluid. Attention is focused on the joint distribution of density and energy fluctuations at coexistence. In the vicinity of the critical point, this distribution is analysed using mixed-field finite-size scaling techniques aided by histogram reweighting methods. The analysis yields highly accurate estimates of the critical point parameters, as well as exposing the size and character of corrections to scaling. In the sub-critical coexistence region the density distribution is obtained by combining multicanonical simulations with histogram reweighting techniques. It is demonstrated that this procedure permits an efficient and accurate mapping of the coexistence curve, even deep within the two phase region.