Models of the nearest surrounding of ions in aqueous solutions of dysprosium chloride

Abstract

Structural organization models are developed using radial distribution functions obtained earlier via XRD analysis for aqueous solutions of dysprosium chloride over a wide range of concentrations under standard conditions. The optimum variants are selected by calculating the theoretical functions for each model and comparing how they agree with experimental functions. Quantitative characteristics of the nearest surrounding of Dy³⁺ and Cl^– ions, e.g., coordination numbers, interparticle distances, and varieties of ion pairs, are established. It is shown that the average number of water molecules in the first coordination sphere of a cation falls from 8.5 to 6 as the concentration grows; the structure of the system over the range of concentrations is determined by noncontact ion associates.