Are Many-body Electronic Polarization Effects Important in Liquid Water?

Many-body electronic polarization effects may be important for an accurate description of aqueous environments. As a result, numerous polarizable water models have been developed to include explicit polarization effects in intermolecular potential functions. In this paper, it is shown for liquid water at ambient conditions that such many-body polarization interactions can be decomposed into effective pairwise contributions using the force-matching (FM) method [Izvekov et al., J. Chem. Phys. 120, 10896 (2004)]. It is found that an effective pairwise water model obtained by the FM method can accurately reproduce various bulk structural and thermodynamic properties obtained from an accurate fully polarizable water model. In addition, the effective pairwise water model also provides a reasonable description of the water liquid-vapor interface, thus exhibiting a degree of transferability to heterogeneous environments. These results suggest that the role and importance of many-body electronic polarization effects in aqueous systems might be fruitfully explored relative to the best possible pairwise decomposable bulk phase model as the reference state.