The effects of charge transfer on the properties of liquid water

A method for treating charge transfer interactions in classical potential models is developed and applied to water. In this method, a discrete amount of charge is transferred for each hydrogen bond formed. It is designed to be simple to implement, to be applicable to a variety of potential models, and to satisfy various physical requirements. The method does not transfer charge at large intramolecular distances, it does not result in a conductive liquid, and it can be easily parameterized to give the correct amount of charge transfer. Two charge transfer models are developed for a polarizable and a non-polarizable potential. The models reproduce many of the properties of liquid water, including the structure, the diffusion constant, and thermodynamic properties over a range of temperatures.