Testing the relevance of effective interaction potentials between highly charged colloids in suspension

J. Dobnikar; R. Castañeda-Priego; H. H. von Grünberg; E. Trizac

doi:10.1088/1367-2630/8/11/277

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Testing the relevance of effective interaction potentials between highly charged colloids in suspension

J. Dobnikar·R. Castañeda-Priego·H. H. von Grünberg·E. Trizac

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Abstract

Combining cell and Jellium model mean-field approaches, Monte Carlo together with integral equation techniques, and finally more demanding many-colloid mean-field computations, we investigate the thermodynamic behavior, pressure and compressibility of highly charged colloidal dispersions, and at a more microscopic level, the force distribution acting on the colloids. The Kirkwood-Buff identity provides a useful probe to challenge the self-consistency of an approximate effective screened Coulomb (Yukawa) potential between colloids. Two effective parameter models are put to the test: cell against renormalized Jellium models.

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J. Dobnikar, R. Castañeda-Priego, H. H. von Grünberg, E. Trizac. 2006-09-22. Testing the relevance of effective interaction potentials between highly charged colloids in suspension. https://doi.org/10.1088/1367-2630%2F8%2F11%2F277

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