Influence of the Drude charge value on the performance of polarisable water model: A test for microscopic and macroscopic parameters

We analyzed the influence of the Drude charge value on the main macroscopic properties of water given by the SWM4-NDP water model (including density, static dielectric constant, self-diffusion constant, and surface tension). Our results show that (in general) the properties of model water do depend on the Drude charge value. We also provide an estimate for the Drude charge value (− 10e) above which the point-dipole limit is achieved with good accuracy. In this paper we also discuss the differences in the convergence behaviour of different model water properties. Based on the obtained results we developed a new re-parameterised version of the SWM4-NDP model (SWM4-NDP10e) where the point-dipole limit condition is satisfied. We show that the model reproduces well important macroscopic as well as microscopic properties of water at ambient conditions.