Estimation of the pressure with computer simulation

Abstract

Several methods for estimating the entropy and the chemical potential μ with computer simulation have recently been described. The combination of these methods permits one to calculate the pressure P. Such a calculation is demonstrated here for a Monte Carlo simulation of the square lattice gas, in the canonical ensemble, above and below the critical temperature. The results are in excellent agreement with the exact solution when this is available. In the two-phase region, below the critical temperature, no loops in the N/V - P and N/V - μ curves are detected. To the best of our knowledge this is the first time that the pressure of a lattice gas model in the canonical ensemble is estimated with computer simulation.