Date of this Version
Results are presented for a precise calculation, based on the deformation dipole model with short-range repulsive interactions between second-neighbor negative ions, of the normal-mode frequency distribution of CsF. The extreme properties of this crystal are reflected in the unusual appearance of the distribution. From these results, we can also predict the form of the second-order Raman spectrum of CsF for two alternative assumptions regarding the Raman polarizability tensor. Both spectra are unusual in that they consist almost entirely of very sharp, clearly separated lines. Furthermore, the spectra corresponding to these two assumptions are very different and should be easily distinguishable experimentally.