Ewald summation technique for interaction site models of polar fluids

A computer adapted fluctuation formula for the calculation of the wavevector- and frequency-dependent dielectric permittivity for interaction site models of polar fluids within the Ewald summation technique is proposed and applied to molecular dynamics simulations of the TIP4P water. The formula is analyzed and optimal parameters of the Ewald method are identified. A comparison of the obtained results with those evaluated within the reaction field approach is made.