Calculating the low temperature vapour line by Monte Carlo

Abstract

A combination of canonical and grand-canonical ensemble Monte Carlo calculations, together with the virial expansion, have been used to calculate the thermodynamic properties of the liquid/vapour co-existence curve of the (6 : 12) Lennard-Jones fluid for reduced temperatures, [Ttilde] ⩽ 1·1. The results for the liquid density and energy and the latent heat of vaporization are believed to be precise, with the exception of the point at [Ttilde]=1·1 which may lie outside the range of the function fitting the liquid phase Monte Carlo data. The liquid density and the saturated vapour pressure are in very good agreement with the results of perturbation theory. The latent heat of vaporization does not agree well with the experimental data for argon though the fit to liquid density and internal energy is good.