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The Foam Analogy in Charged Colloidal Crystals

W. Kung·P. Ziherl·R. D. Kamien
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Abstract

We model charged colloidal suspensions using an analogy with foams. We study the solid--solid phase transitions of these systems as a function of particle volume-fraction and ionic strength. The screened Coulomb interaction is replaced by an interaction between walls of the Voronoi cells around each particle. We fit the surface charge to reproduce the phase diagram for the charged suspension studied by Sirota, et al. [Phys. Rev. Lett. 62, 1524 (1989)]. With this fit parameter we are able to calculate the elastic moduli of the system and find good agreement with the available data.

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W. Kung, P. Ziherl, R. D. Kamien. 2001-11-29. The Foam Analogy in Charged Colloidal Crystals. https://doi.org/10.1103/physreve.65.050401

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