GENERALIZED ELECTRON GAS-DRUDE MODEL THEORY OF INTER-MOLECULAR FORCES

An electron gas theory of intermolecular forces which unifies the treatment of long- and short-range effects is improved and extended in several ways. (1) The shell polarization model takes full account of the forces from both cores and shells. (2) The amount of polarization is calculated with full self-consistency in the forces on the shells. (3) Exact agreement with the known long-range forces is achieved by an effective mass description of the shell dynamics. (4) Anisotropic polarizations appropriate to a linear molecule interacting with an atom are included. The theory is applied to the systems H2-He, H2-Ar and HCl-Ar. Fairly good agreement is found with the available but incomplete experimental data including the angle dependence of the potentials. However, some evidence suggest that the predicted repulsion is somewhat too large when a rare gas atom approaches a hydrogen atom along the molecular axis. © 1979 American Institute of Physics.