A Generalized Ewald Decomposition for Screened Coulomb Interactions

A Generalized Ewald Decomposition for Screened Coulomb Interactions

Article:

"A Generalized Ewald Decomposition for Screened Coulomb Interactions"

Gautham Dharuman, Liam G. Stanton, James N. Glosli, Michael S. Murillo

The Journal of Chemical Physics, Volume 146, Issue 2, January 2017

Link: http://dx.doi.org/10.1063/1.4973842


Abstract
Medium-range interactions occur in a wide range of systems, including charged-particle systems with varying screening lengths. We generalize the Ewald method to charged systems described by interactions involving an arbitrary dielectric response function epsilon(k). We provide an error estimate and optimize the generalization to find the break-even parameters that separate a neighbor list-only algorithm from the particle-particle particle-mesh algorithm. We examine the implications of different choices of the screening length for the computational cost of computing the dynamic structure factor. We then use our new method in molecular dynamics simulations to compute the dynamic structure factor for a model plasma system and examine the wave-dispersion properties of this system.