Long-range overlap dipoles for inert gas diatoms

Abstract

It is assumed that the overlap contribution to the dipole moment of a pair of colliding inert gas atoms can be approximated by electron exchange between the undistorted Hartree-Fock atoms. Calculations of this overlap dipole for the six hetero-diatoms formed from He, Ne, Ar and Kr are presented and compared with the calculations of Matcha and Nesbet. A calculated dipole for HeAr, including dispersion, is in very good agreement with that derived from collision-induced absorption experiments. Calculations for the odd electron systems HeH, HeLi and HeNa are also presented and compared with more elaborate calculations. The comparison is satisfactory for HeLi and HeNa but not for HeH.