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arXiv · 1401.2064

Quantifying the effects of neglecting many-body interactions in coarse-grained models of complex fluids

Douglas J. Ashton·Nigel B. Wilding
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Abstract

We describe a general simulation scheme for assessing the thermodynamic consequences of neglecting many-body effects in coarse-grained models of complex fluids. The method exploits the fact that the asymptote of a simple-to-measure structural function provides direct estimates of virial coefficients. Comparing the virial coefficients of an atomistically detailed system with those of a coarse-grained version described by pair potentials, permits the role of many-body effects to be quantified. The approach is applied to two models: (i) a size-asymmetrical colloid-polymer mixture, and (ii) a solution of star polymers. In the latter case, coarse-graining to an effective fluid described by pair potentials is found to neglect important aspects of the true behaviour.

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Douglas J. Ashton, Nigel B. Wilding. 2014-01-09. Quantifying the effects of neglecting many-body interactions in coarse-grained models of complex fluids. https://doi.org/10.1103/physreve.89.031301

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