On Ion and Molecular Polarization of Halides in Water

The high polarizability of halide anions affects, in aqueous solutions, many phenomena ranging from hydrogen bond dynamics to water interfaces' structure. In this Letter dipolar interactions of halides in water are investigated through Car-Parrinello Molecular Dynamics simulations. Contrary to previous studies, a different polarization of first and second hydration shell water molecules is found. The analysis hints that existing classical polarizable force fields lack a description of short-range interactions which causes an overestimation of polarization effects.