Raman spectroscopy of oxyanions in molten salts. Part 2.—Correlation of the symmetric stretching frequency with polarizing power and polarizability of the cation

Abstract

Frequencies of the symmetrical stretching vibration, ν₁, of the anion in various molten salts have been measured by Raman spectroscopy as a function of temperature and composition. Data have been obtained for Li₂SO₄, Na₂SO₄, Ag₂SO₄, Li₂SO₄–K₂SO₄, Na₂CO₃, K₂CO₃, Li₂CO₃–K₂CO₃, NaClO₃, AgClO₃ and NaClO₃–AgClO₃ melts. These frequencies were combined with literature data on these and other oxyanions and correlated with the logarithm of the product of the cation polarizing power and polarizability, Pα, as proposed by Brooker and Bredig. Good correlation was found for the NO^–₃, SO^2–₄ and CO^2–₃ ions. Deviations from linearity were found for the ClO^–₃ and IO^–₃ ions.