Raman spectroscopy of oxyanions in molten salts. Part 1.—Analysis of the asymmetric stretching band in molten Li2SO4 and Li2SO4–K2SO4 mixtures

Abstract

The Raman spectra of molten Li₂SO₄ and of seven molten Li₂SO₄–K₂SO₄ mixtures have been recorded at temperatures to 1240 K. The broad band at 1100–1190 cm^–1(assigned to ν₃ of SO₄^2– in T_d symmetry) has been observed to split in these melts, indicating the presence of structures with C_3v and C_s symmetry. These findings are in agreement with models proposed from X-ray diffraction studies.