Short-range forces and the dielectric properties of solid argon

Abstract
The observed density dependence of the optical dielectric constant of solid argon is fitted to a theory of the shift of the ultra-violet excitation frequency derived from the Dick-Overhauser shell model. The model is also applied in an approximate way to formulate a theory of the defect induced infra-red absorption in solid argon for which a rigorous sum rule is derived. The values of the parameters resulting are used to estimate very roughly the change in energy resulting from electronic distortion of atoms around a vacancy in the solid. It is concluded that this change could be of order 10% or more of the rigid atom vacancy energy.