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arXiv · 1503.06615

The effective colloid interaction in the Asakura-Oosawa model. Assessment of non-pairwise terms from the virial expansion

Andrés Santos·Mariano López de Haro·Giacomo Fiumara·Franz Saija
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Abstract

The relevance of neglecting three- and four-body interactions in the coarse-grained version of the Asakura-Oosawa model is examined. A mapping between the first few virial coefficients of the binary nonadditive hard-sphere mixture representative of this model and those arising from the coarse-grained (pairwise) depletion potential approximation allows for a quantitative evaluation of the effect of such interactions. This turns out to be especially important for large size ratios and large reservoir polymer packing fractions.

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Andrés Santos, Mariano López de Haro, Giacomo Fiumara, Franz Saija. 2015-06-15. The effective colloid interaction in the Asakura-Oosawa model. Assessment of non-pairwise terms from the virial expansion. https://doi.org/10.1063/1.4922031

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