Langevin dynamics study of NaCl electrolyte solutions at different concentrations

Langevin dynamics simulations of NaCl electrolyte solutions at 25° C and several concentrations (0.1–2 M) were performed. The solvent-averaged potentials of Pettitt and Rossky were assumed. These potential models show remarkable oscillatory shapes that are associated with the discrete structure of the solvent. The changes in the ionic structure and self-diffusion coefficients with the increase of the concentration are discussed. Special attention is paid to both the mean number of ionic pairs and the time that these ionic associations survive. The results are compared with the ones obtained from other potential models and with the available experimental data.