Collisional polarizability anisotropies of the noble gases

We present a simple approximate calculation of the pair polarizability anisotropy β(R) of interacting inert gas atoms, including overlap effects. The overlap contribution to β(R) is found to be relatively long-range and to have an exponential form. We compare our results with recent ab initio Hartree-Fock calculations and experimental low density depolarized scattering spectra; agreement is excellent.