Structure of molten nitrates. Part 4.—Relative intensity study in Raman spectra

Abstract

The intensities of the symmetrical stretching frequency of the nitrate ion in melts of univalent metal nitrates are reported relative to the intensity in NaNO₃. Whereas the intensity for the alkali metals shows a gradual decrease with increasing values for z/r in the alkali metal nitrates, the values for AgNO₃ and TlNO₃ are much greater and appear unrelated to the z/r of the cation. The results are discussed in terms of covalent interactions the most important of which appears to be the donation of π electrons from the metal atom to the nitrate ion. The relative intensities of the symmetrical stretching frequencies in LiClO₄ and NaClO₃ are also included.