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How to mesh up Ewald sums (II): An accurate error estimate for the P3M algorithm

Markus Deserno·Christian Holm
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Abstract

We construct an accurate estimate for the root mean square force error of the particle-particle-particle-mesh (P3M) algorithm by extending a single particle pair error measure which has been given by Hockney and Eastwood. We also derive an easy-to-use analytic approximation to the error formula. This allows a straightforward and precise determination of the optimal splitting parameter (as a function of system specifications and P3M parameters) and hence knowledge of the force accuracy prior to the actual simulation. The high quality of the estimate is demonstrated in several examples.

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Markus Deserno, Christian Holm. 1998-07-07. How to mesh up Ewald sums (II): An accurate error estimate for the P3M algorithm. https://doi.org/10.1063/1.477415

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