Temporal and spatial properties of ion solvation in simple liquids

Abstract

A research of the diffusion of an ion in a liquid is carried out. Dependences of the diffusion coefficient on the ion-molecule potential, ion mass, liquid temperature and density are defined. The results are related to the ion solvation. The classical molecular dynamics method is applied. The effect of the ion solvation is discovered. Firstly, ion mass has no influence on the diffusion coefficient. This is because the total mass of the cluster formed by the ion and the ion solvation shell varies slightly while the mass of the ion changes significantly. In addition, the dependence on short-range interaction is found to be rather weak. The dependence of the diffusion coefficient on long-range interaction is found to be really stronger than on short- range. The ion velocity autocorrelation function calculated reveals a strong oscillatory character superimposed on the conventional functional liquid-type form. It reflects the oscillations of the ion inside the solvation shell. The relation between the ion mobility and temperature is found to be of the Arrhenius-type form.