Role of nonadditive forces on the structure and properties of liquid water.

The role of nonadditive interactions on the structure and dielectric properties of water is investigated at different temperatures using molecular dynamics. A new intermolecular potential is developed which contains an ab initio description of two-body additive interactions plus nonadditive contributions from both three-body interactions and polarization. Polarization is the main nonadditive influence, resulting in improved agreement with experiment for the radial distribution function, dielectric constant, and dipole moment. A comparison is also made with other widely used intermolecular potentials. The new potential provides a superior prediction of the dielectric constant and dipole moment. It also predicts the relative contribution of hydrogen bonding better than the SPC/E potential [Berendsen et al., J. Phys. Chem. 91, 6269 (1987)].