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Three-dimensional Binary Superlattices of Oppositely-charged Colloids

Paul Bartlett·Andrew Campbell
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Abstract

We report the equilibrium self-assembly of binary crystals of oppositely-charged colloidal microspheres at high density. By varying the magnitude of the charge on near equal-sized spheres we show that the structure of the binary crystal may be switched between face-centered cubic, cesium chloride and sodium chloride. We interpret these transformations in terms of a competition between entropic and Coulombic forces.

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Paul Bartlett, Andrew Campbell. 2005-04-29. Three-dimensional Binary Superlattices of Oppositely-charged Colloids. https://doi.org/10.1103/physrevlett.95.128302

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