DENSITY-SCALING MONTE-CARLO STUDY OF SUBCRITICAL LENNARD-JONESIUM

In density-scaling Monte Carlo (DSMC) one covers a substantial range o f density in a single simulation, obtaining the free energy as well as the usual ensemble averages; a further advantage is the avoidanee of quasiergodicity. The method is applied to the subcritical Lennard-Jone s fluid. At kT/epsilon = 1.2, the density range 0.02 less-than-or-equa l-to rhosigma3 less-than-or-equal-to 0.80 was studied in four overlapp ing DSMC runs; data was extracted at intervals of 0.005, i.e., at a to tal of 157 densities. Free energies, energies, and pressures are found with striking precision, and reasonable estimates are obtained for he at capacity, compressibility, and kinetic pressure. The liquid-gas pha se transition is thus characterized with a precision not otherwise pos sible.