Thermodynamic Properties of Sutherland Fluids from an Analytical Perturbation Theory

Analytical expressions are obtained for the thermodynamic properties of fluids with potentials consisting of a spherical hard core plus an attractive tail of the form 1 r# (Sutherland fluids). To this end, use is made of the Barker Henderson perturbation theory together with an analytical expression for the first coordina- tion shell of the radial distribution function of the reference hard-sphere fluid. This expression was derived previously on the basis of the analytical solution of the Percus Yevick iIntegral equation theory. The results are compared with available simulation data for a wide range of densities, temperatures, and values of the potential parameter #. The overall agreement is good, and the accuracy is similar to that obtained using more accurate solutions for the radial distribu- tion function of the hard-sphere fluid leading to nonanalytical expressions for the thermodynamic properties of the fluid considered.