VIRIAL-COEFFICIENTS OF HARD-SPHERE MIXTURES

The fourth and fifth virial coefficients of binary hard-sphere mixture s have been calculated for size ratios R greater than or equal to 0.05 and R=sigma(22)/sigma(11). The composition independent partial virial coefficients have been expressed in terms of the Mayer diagrams. The corresponding modified star diagrams were evaluated by Monte Carlo int egration. The results are compared with predictions of the Boublik [J. Chem. Phys. 53, 471 (1970)] and Mansoori et al. [J. Chem. Phys. 54, 1 531 (1971)] equation of state, and the excellent agreement gives stron g support to the validity of that equation of state for very asymmetri c mixtures.