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arXiv · 1111.2705

Computing the local pressure in molecular dynamics simulations

Thomas Lion·Rosalind J. Allen
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Abstract

Computer simulations of inhomogeneous soft matter systems often require accurate methods for computing the local pressure. We present a simple derivation, based on the virial relation, of two equivalent expressions for the local (atomistic) pressure in a molecular dynamics simulation. One of these expressions, previously derived by other authors via a different route, involves summation over interactions between particles within the region of interest; the other involves summation over interactions across the boundary of the region of interest. We illustrate our derivation using simulations of a simple osmotic system; both expressions produce accurate results even when the region of interest over which the pressure is measured is very small.

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Thomas Lion, Rosalind J. Allen. 2012-07-30. Computing the local pressure in molecular dynamics simulations. https://doi.org/10.1088/0953-8984%2F24%2F28%2F284133

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