Effects of polarizability on the hydration of the chloride ion

Polarizable and nonpolarizable potential models for both water and chloride are used to address the issue of surface vs interior solvation of the chloride ion in Cl(H2O)(n)(-) clusters, for n up to 255. We find that, even for the largest clusters, simulations with polarizable water models show that the chloride ion is preferentially solvated near the surface of the cluster. This behavior is not observed with a nonpolarizable model. The many-body effects are not directly responsible for this solvation behavior; polarizability appears to be important primarily for its role in facilitating a larger average dipole moment on the water model. Polarizability on the chloride ion is not found to have a substantial effect on the structure of the clusters.