关键词: perturbation theory;mean spherical approximation;molecular simulation;internal energies

Abstract: A comprehensive study on various internal energies for the dipolar hard sphere fluids,
including Stockmayer fluids, the mixtures of Lennard-Jones and Stockmayer and Stockmayer
fluids and the electrolyte solutions is reported based on the perturbation theory and mean
spherical approximation. Compared with the results of molecular simulations, it is shown
that the perturbation theory is better than the mean spherical approximation.

Key words: perturbation theory, mean spherical approximation, molecular simulation, internal energies