Alexander P. Lyubartsev and Aatto Laaksonen
Division of Physical Chemistry, Arrhenius Laboratory, Stockholm University, S 106 91, Stockholm, Sweden
Suggested earlier method of reconstructing of interaction potentials from radial distribution functions was used to derive effective interaction potentials of Na+ and Cl- ions in aqueous solution. The reference ion-ion radial distribution functions were determined in molecular-dynamics simulations of ions in water and were then used as input data for effective potential calculations which takes into account molecular structure of water in an average way. The obtained effective potentials were then used in Monte Carlo simulations on a large scale in which the osmotic and activity coefficients of ions were calculated. A good agreemnet with experimental data was observed. Effects of three-body interactions and of concentration dependences of the effective potentials are discussed.
pacs 61.20Ja,05.20.Gg,02.70-c,61.20.Qg
Paper (Postscript file)