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arXiv · 1711.00006

Better than counting: Density profiles from force sampling

Daniel de las Heras·Matthias Schmidt
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Abstract

Calculating one-body density profiles in equilibrium via particle-based simulation methods involves counting of events of particle occurrences at (histogram-resolved) space points. Here we investigate an alternative method based on a histogram of the local force density. Via an exact sum rule the density profile is obtained with a simple spatial integration. The method circumvents the inherent ideal gas fluctuations. We have tested the method in Monte Carlo, Brownian Dynamics and Molecular Dynamics simulations. The results carry a statistical uncertainty smaller than that of the standard, counting, method, reducing therefore the computation time.

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Daniel de las Heras, Matthias Schmidt. 2017-10-31. Better than counting: Density profiles from force sampling. https://doi.org/10.1103/physrevlett.120.218001

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