Theory of Brillouin-scattering intensity in rare-gas crystals

Abstract

Existing Brillouin-scattering intensity measurements on rare-gas crystals are in poor agreement with the point-dipole theory of interaction polarizabilities. We generalize this theory to include short-range overlap and exchange effects and show that large changes in elasto-optic (Pockels) coefficients result, and that agreement with experiment is significantly improved. Finally, we suggest that experimental data on Pockels coefficients may be used to determine the behavior of pair-polarizability anisotropies at the crystal nearest-neighbor separation.