Dynamic properties of the NaCl–methanol–water systems—MD simulation studies

Abstract

Dynamical properties in methanol–water mixtures and ternary solutions containing NaCl have been investigated by MD simulation. The self-diffusion coefficients (D) of methanol and water computed from MD results are in very good agreement with the experimental data. The D-values in the bulk solvent and the ionic shells have been calculated. The presence of ions does not affect the dynamics of the bulk solvent, whereas solvent translations in the ionic shells are significantly retarded. An exchange of the solvent molecules between the ionic shells and the bulk has been investigated. The residence time of methanol and water in the Na⁺ shell and the methanol residence time in the Cl⁻ shell are longer that the characteristic time of translations. The residence time of the solvent molecules in the coordination shells of other solvent molecules has been computed. Association of water molecules in the methanol rich solution has been found.