The dielectric properties of liquid water are studied using an empirical potential model treating the monomers as flexible molecules with short-range interactions between oxygens and Coulomb interactions between charges situated on the individual atoms. Satisfactory results for the static dielectric constants at 259, 300, and 350 K are obtained from long simulation runs; these constitute a significant improvement over recent calculations using other potential models. Time correlation functions of dipole moment and single molecule orientation are evaluated. In the supercooled state an enhanced slowing down in the temporal decay of polarization fluctuations occurs, a behavior essentially absent in the single molecule reorientations. Good agreement is found in the self-diffusion coefficient over the entire temperature range.
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