Abstract: Several classical water models (SPC, TIPnP (n=3-5)) and polarizable models (POL3, AMOEBA, SPC-FQ, TIP4P-FQ), combining the results of ab initio methods were employed to study the properties of water clusters, such as structures, dipoles, induced dipoles, charge transfer, polarized energies, many-body energies and binding energies, and were evaluated against the related literature works. Whether the polarized effects can be neglected in the modelng of water clusters was judged by the total potential and the decomposed energy terms. All in all, the polarizable water models, especially the induced multiple model (AMOEBA), do better job than classical fixed charge models. Fluctuating charge and four sites model is more realistic to be applied to the biological sytems in consideration of the balance of efficiency and accuracy. The comparable studies of this paper provide a reference for developing the polarized models and applying themto other systems.

Key words: Water molecule, Force field, Cluster, Electrostatic polarization