Generalized Moment Correction for Long-Ranged Electrostatics

Summary, in English

Describing long-ranged electrostatics using short-ranged pair potentials is appealing because the computational complexity scales linearly with the number of particles. The foundation of the approach presented here 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 are applicable also for dipole-dipole interactions.

• Author: Björn Stenqvist; Vidar Aspelin; Mikael Lund
• Department/s: Physical Chemistry; Computational Chemistry; LINXS - Institute of advanced Neutron and X-ray Science; eSSENCE: The e-Science Collaboration
• Publishing year: 2020
• Language: English
• Pages: 3737-3745
• Publication/Series: Journal of Chemical Theory and Computation
• Volume: 16
• Issue: 6
• Links: http://dx.doi.org/10.1021/acs.jctc.9b01003
• Document type: Journal article
• Publisher: The American Chemical Society (ACS)
• Topic: Theoretical Chemistry (including Computational Chemistry)
• Status: Published
• ISBN/ISSN/Other: ISSN: 1549-9618