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Configurational temperatures and interactions in charge-stabilized colloid

Yilong Han·David G. grier
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Abstract

We demonstrate that the configurational temperature formalism can be derived from the classical hypervirial theorem, and introduce a hierarchy of hyperconfigurational temperature definitions, which are particularly well suited for experimental studies. We then use these analytical tools to probe the electrostatic interactions in monolayers of charge-stabilized colloidal spheres confined by parallel glass surfaces. The configurational and hyperconfigurational temperatures, together with a novel thermodynamic sum rule, provide previously lacking self-consistency tests for interaction measurements based on digital video microscopy, and thereby cast new light on controversial reports of confinement-induced like-charge attractions. We further introduce a new method for measuring the pair potential directly that uses consistency of the configurational and hyperconfigurational temperatures as a set of constraints for a model-free search.

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Yilong Han, David G. grier. 2004-07-27. Configurational temperatures and interactions in charge-stabilized colloid. https://doi.org/10.1063/1.1844351

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