First quantum corrections to second virial coefficients for anisotropic interactions: Simple, corrected formulaa)

A simple formula for the first quantum correction to the second virial coefficient, valid for the interaction of any like or unlike combination of atoms, diatomics, spherical top, or symmetric top molecules is given. It is found that the commonly used formulas of Wang Chang contain an error that omits an anisotropic contribution. The sizes of the different contributions to the quantum correction are discussed. As examples, calculations for He–SF6 and He–CO2 are reported.