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Critical behavior in colloid-polymer mixtures: theory and simulation

F. Lo Verso·R. L. C. Vink·D. Pini·L. Reatto
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Abstract

We extensively investigated the critical behavior of mixtures of colloids and polymers via the two-component Asakura-Oosawa model and its reduction to a one-component colloidal fluid using accurate theoretical and simulation techniques. In particular the theoretical approach, hierarchical reference theory [Adv. Phys. 44, 211 (1995)], incorporates realistically the effects of long-range fluctuations on phase separation giving exponents which differ strongly from their mean-field values, and are in good agreement with those of the three-dimensional Ising model. Computer simulations combined with finite-size scaling analysis confirm the Ising universality and the accuracy of the theory, although some discrepancy in the location of the critical point between one-component and full-mixture description remains. To assess the limit of the pair-interaction description, we compare one-component and two-component results.

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F. Lo Verso, R. L. C. Vink, D. Pini, L. Reatto. 2006-03-22. Critical behavior in colloid-polymer mixtures: theory and simulation. https://doi.org/10.1103/physreve.73.061407

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