Monte Carlo calculations of the equation of state of the square-well fluid as a function of well width

Some results of Monte Carlo simulations for the square-well fluid for 1.125 ≤ λ ≤ 2, where λ-1 is the width of the well, are presented and compared with perturbation theory and, λ = 1.85, with the BGY theory. In general, we find perturbation theory to be more reliable than the BGY theory. For λ > 1.5, perturbation theory is generally satisfactory. However, for λ < 1.5, the pressures calculated from perturbation theory become less satisfactory as λ is decreased. © 1980 American Institute of Physics.