Institute of Fundamental Technological Research

A method for obtaining the differential cross section for any realistic intermolecular potential (e.g., the Lennard-Jones potential), is presented. This approach avoids ad hoc approximations, such as the finite-range potentials and angular cutoffs, and can be used for accurate calculations of the transport coefficients. It is shown that neither the hard spheres nor the soft spheres (variable hard spheres) models are consistent with a realistic potential, even in the limit of large relative molecular velocity.