A Study of Solvation-Shell Symmetry in Electrolyte Solutions Using Quadrupolar NMR Relaxation of the Nuclei of Monoatomic Ions

Abstract

The spin–lattice relaxation rates of⁷Li,²³Na,²⁷Al,⁷¹Ga, and¹³⁹La nuclei in electrolyte solutions have been investigated as functions of the isotopic composition of the solvent. The results show that quadrupolar relaxation of the nuclei of monoatomic ions is extremely sensitive to the symmetry of the solvation shells. The data are compared to the results for the²H and¹⁷O nuclei of the solvent molecules and the¹⁴N nucleus of the nitrate anion. A semiquantitative description of the observed effects is given.