  Describing long-ranged electrostatics using short-ranged pair potentials is
appealing since the computational complexity scales linearly with the number of
particles. The foundation of this approach is to mimic the long-ranged medium
response by cancelling electric multipoles within a small cutoff sphere. We
propose a rigorous and formally exact new method that cancels up to infinitely
many multipole moments and is free of operational damping parameters often
required in existing theories. Using molecular dynamics simulations of water
with and without added salt, we discuss radial distribution functions,
Kirkwood-Buff integrals, dielectrics, diffusion coefficients, and angular
correlations in relation to existing electrostatic models. We find that the
proposed method is an efficient and accurate alternative for handling
long-ranged electrostatics as compared to Ewald summation schemes. The
methodology and proposed parameterization is applicable also for dipole-dipole
interactions.
