Chemical potential for simple fluids from equations of state

Abstract

The chemical potential for both the hard-sphere and the Lennard-Jones systems is calculated from analytical equations of state proposed in the literature and results are compared with data obtained by different authors from computer simulations. Eighteen equations of state for hard spheres, some of them recently published, were considered, and for the Lennard-Jones system three semi-empirical equations and two semi-theoretical ones, one of the latter being proposed by us in a previous work. Good agreement, except for particular expressions and/or particular temperature or density ranges, is found for most cases and for both hard-sphere and Lennard-Jones fluids. Our results indicate that the use of expressions which are more complex than the Carnahan—Starling equation for hard spheres or than our proposal for Lennard-Jones fluids is not needed to obtain the chemical potential accurately.