The optical and spectroscopic properties of the sulfate ion in various crystalline environments

Abstract

The electronic polarizability components of the sulfate ion in LiKSO₄, KNaSO₄, K₂SO₄, Na₂SO₄, and K₂Mg₂(SO₄)₃ were calculated from the optical refractive indices using a point dipole model. The values obtained were discussed in terms of the immediate crystalline environment of the sulfate ion. The frequencies of the transverse and longitudinal internal optic modes were measured by polarized Raman scattering experiments and estimated from near‐normal incidence reflectivity spectra. The frequency data were analyzed in a molecular dipole model formalism with static crystal field frequencies and molecular dipole moment derivatives of the internal modes of the sulfate ion being reported and discussed.