AN EXTENDED EMPIRICAL VALENCE-BOND MODEL FOR DESCRIBING PROTON-TRANSFER IN H+(H2O)(N) CLUSTERS AND LIQUID WATER

An extended empirical valence bond Hamiltonian for performing molecula r dynamical simulations of an excess proton in water is proposed. This model includes an arbitrary number of valence states and allows for a consistent description of the delocalized electronic structure around the excess charge. The non-additive force field thus obtained was use d to investigate equilibrium properties and finite temperature dynamic s of small H+(H2O)(n) clusters, as well as proton transfer dynamics of an excess proton in liquid water. (C) 1998 Elsevier Science B.V.