Charge Renormalization, Effective Interactions, and Thermodynamics of Deionized Colloidal Suspensions

Alan R. Denton

doi:10.1088/0953-8984/20/49/494230

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arXiv · 0809.3776

Charge Renormalization, Effective Interactions, and Thermodynamics of Deionized Colloidal Suspensions

Alan R. Denton

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Abstract

Thermodynamic properties of charge-stabilised colloidal suspensions depend sensitively on the effective charge of the macroions, which can be substantially lower than the bare charge in the case of strong counterion-macroion association. A theory of charge renormalization is proposed, combining an effective one-component model of charged colloids with a thermal criterion for distinguishing between free and associated counterions. The theory predicts, with minimal computational effort, osmotic pressures of deionized suspensions of highly charged colloids in close agreement with large-scale simulations of the primitive model.

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Alan R. Denton. 2008-09-22. Charge Renormalization, Effective Interactions, and Thermodynamics of Deionized Colloidal Suspensions. https://doi.org/10.1088/0953-8984%2F20%2F49%2F494230

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