Density-scaling Monte Carlo study of subcritical Lennard-Jonesium

Abstract

In density-scaling Monte Carlo (DSMC) one covers a substantial range of density in a single simulation, obtaining the free energy as well as the usual ensemble averages; a further advantage is the avoidance of quasiergodicity. The method is applied to the subcritical Lennard-Jones fluid. At kT/∈= 1.2, the density range 0.02≤ρσ3≤0.80 was studied in four overlapping DSMC runs; data was extracted at intervals of 0.005, i.e., at a total of 157 densities. Free energies, energies, and pressures are found with striking precision, and reasonable estimates are obtained for heat capacity, compressibility, and kinetic pressure. The liquid-gas phase transition is thus characterized with a precision not otherwise possible. © 1993 American Institute of Physics.