Calculation of the second virial coefficient of nonspherical molecules: Revisited

An accurate Hartree–Fock dispersion individually damped (HFD-ID) potential type improved by Boyes for argon has been used as a core potential to calculate both the spherical and nonspherical contributions to the second virial coefficient of simple molecules. The auxiliary functions that occur in the perturbation terms for calculating the nonspherical contributions, have been calculated numerically and are tabulated over a wide range of temperatures from T^*=0.5 to T^*=10, where T^*=kT/ and is the potential well-depth. By fitting the well-depth and the position of the minimum in the core potential, we have calculated the second virial coefficient of N₂, O₂, CO, NO, and CO₂ over the whole temperature range reported in the literature. The calculated results are compared with the large body of experimental data in the literature, and with the pervious calculations by Boushehri et al. (1987). The agreement with both experimental data and theoretical calculations is quite good.