Structure of aqueous solutions: Infrared spectra of the water librational mode in solutions of monovalent halides

Abstract

The variations of the infrared librational mode of water with concentration of added salt have been examined at 30�C for solutions of NH4F, NH4Cl, NH4Br, NH4I, LiCl, LiBr, NaCl, NaBr, NaI, KCl, KBr and KI. The data indicate that water in the primary hydration sheath can be distinguished from the remainder of the water and primary hydration numbers have been estimated. It is shown that in general the larger the ion the greater the change to the spectral band. The ammonium fluoride is shown to be unique in producing little disturbance of the water structure.

Deuteron Spin -Lattice Relaxation Times in Undercooled Aqueous Potassium - and Cesium Halide Solutions

“…T I 0 must be related to an attempt frequency for barrier crossing, hence corresponds to the inverse of an average librational frequency of the primary hydration water component [29] and has been calculated accordingly. Because of the weaker temperatures dependence, these anisotropic fluctuations become the faster modes at low temperatures and provide the more efficient relaxation channels, hence dominate the relaxation.…”

The p, T, c dependence of deuterium spin-lattice relaxation times in undercooled NaCl/D2O and NaI/D2O solutions

“…From experimental determinations of the frequency of the band maximum of the primary hydration water component in aqueous sodium halide solutions [ 48 ] the corresponding rio are calculated and are compiled in table 2.…”

Multi‐Nuclear Relaxation Time Studies in Undercooled Aqueous Electrolytes

“…The preexponential factor corresponds to an attempt frequency for barrier crossing, hence is given by an average librational frequency of hydration water molecules [12].…”