Test of Combination Rules for Prediction of Interaction Second Virial Coefficients

The recently proposed argon pair potential of Dymond and Alder is shown to provide a satisfactory two-parameter corresponding states description of the second virial coefficients of the rare gases. The potential is used as a basis for testing various combination rules for predicting interaction second virial coefficients for rare-gas pairs. For helium binary systems, none of the rules tested produces uniformly acceptable results. Only the expression εij = 2εiiεjj / (εii + εjj) appears satisfactory for all pairs not containing helium.