Abstract Second virial coefficients and a large number of Chapman-Cowling collision integrals were calculated for gases obeying an improved intermolecular potential proposed by Aziz et al. [J. Chem. Phys. 94, 1034 (1991)]. The results are tabulated for a large reduced temperature range, kT/ε from 0.1 to 100. The treatment was entirely classical, and no corrections for quantum effects were made. The higher approximations to the transport coefficients were also calculated and tabulated for the same temperature range. These results should be applicable to characterize the bulk properties of various spherical molecules, especially to predict gaseous transport properties. Evaluation of the potential parameters for uranium hexafluoride, together with fitting to second virial coefficient, viscosity, thermal conductivity and self-diffusion data are also presented. This potential appears to have the best overall predictive ability for gaseous hexafluoride data.