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arXiv · 0704.0474

Application of Ewald summations to long-range dispersion forces

Pieter J. in 't Veld·Ahmed E. Ismail·Gary S. Grest
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Abstract

We present results illustrating the effects of using explicit summation terms for the $r^{-6}$ dispersion term on the interfacial properties of a Lennard-Jones fluid and SPC/E water. For the Lennard-Jones fluid, we find that the use of long-range summations, even with a short ``crossover radius,'' yields results that are consistent with simulations using large cutoff radii. Simulations of SPC/E water demonstrate that the long-range dispersion forces are of secondary importance to the Coulombic forces. In both cases, we find that the ratio of box size $L_{\parallel}$ to crossover radius $r_{\rm c}^{\mathbf k}$ plays an important role in determining the magnitude of the long-range dispersion correction, although its effect is secondary when Coulombic interactions are also present.

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Pieter J. in 't Veld, Ahmed E. Ismail, Gary S. Grest. 2007-07-13. Application of Ewald summations to long-range dispersion forces. https://doi.org/10.1063/1.2770730

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