THE INTERMOLECULAR POTENTIALS OF HELIUM AND HYDROGEN (AND FORCE CONSTANTS FOR SOME NON POLAR MOLECULES)
WISCONSIN UNIV-MADISON THEORETICAL CHEMISTRY INST
Pagination or Media Count:
An analysis was made of experimental second-virial-coefficient and viscosity data for He and H to determine the appropriate values of the parameters epsilon depth of the potential energy minimum, r sub m position of the minimum distance between molecules, and alpha a measure of the steepness of the repulsion energy in the intermolecular exp-6 potential expression epsilon1-6alpha6alpha sub e to the alpha1-rr sub m-r sub mr to the 6th power. The treatment was based on an adaptation of the Keesom and Lennard- Jones-procedure Leiden Comm. Suppl. no. 25, 1912 Proc. Roy. Soc. A106463, 1924 for the second virial coefficient. Tabular and graphical comparisons are included for experimental and calculated values of a number of properties of gaseous He and H. Combining rules for the exp-6 potential are presented for predicting the properties of He-H mixtures, and reasonable agreement between theory and experiment is indicated for second virial coefficients, viscosities, and thermal diffusion factors.
- Atomic and Molecular Physics and Spectroscopy