Spherically averaged potential energies of interaction between pairs of methane, carbon tetrafluoride and sulphur hexafluoride molecules have been determined as closely as possible using experimental gaseous viscosity data. Experimental second virial coefficients have then been used to estimate values of the first non zero multipole moment of these molecules. Third virial coefficients calculated with allowance for the triple dipole dispersion interaction agree well with experiment as do calculated self diffusion coefficients for methane.
Journal of the Chemical Society, Faraday Transactions 2: Molecular and Chemical Physics,
Vol. 68 (1972), pp. 1359-1366