Solvation in high-temperature electrolyte solutions. I. Hydration shell behavior from molecular simulation

The behavior of the first hydration shell of species in solution and its re levant thermophysical properties are studied by molecular dynamics of infin itely dilute NaCl aqueous solutions at high temperature. The ion-induced ef fects on the water local properties are assessed in terms of the correspond ing radial profiles for the local density, the local pressure, the local el ectric held, the local dielectric constant, and two alternative types of co ordination numbers, along the near-critical reduced isotherm. T-r = 1.05 an d the supercritical reduced isochore rho(r) = 1.5. Simulation results are d iscussed in the context of their usefulness in enhancing the understanding and the modeling of supercritical aqueous electrolytes. (C) 1999 American I nstitute of Physics. [S0021-9606(99)50902-1].