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arXiv · 1403.3368

Three-body interactions in complex fluids: virial coefficients from simulation finite-size effects

Douglas J. Ashton·Nigel B. Wilding
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Abstract

A simulation technique is described for quantifying the contribution of three-body interactions to the thermodynamical properties of coarse-grained representations of complex fluids. The method is based on comparing the third virial coefficient $B_3$ for a complex fluid with that of an approximate coarse-grained model described by a pair potential. To obtain $B_3$ we introduce a new technique which expresses its value in terms of the measured volume-dependent asymptote of a certain structural function. The strategy is applicable to both Molecular Dynamics and Monte Carlo simulation. Its utility is illustrated via measurements of three-body effects in models of star polymer and highly size-asymmetrical colloid-polymer mixtures.

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Douglas J. Ashton, Nigel B. Wilding. 2014-05-02. Three-body interactions in complex fluids: virial coefficients from simulation finite-size effects. https://doi.org/10.1063/1.4883718

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