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Anomalous interactions in confined charge-stabilized colloid

David G. Grier·Yilong Han
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Abstract

Charge-stabilized colloidal spheres dispersed in weak 1:1 electrolytes are supposed to repel each other. Consequently, experimental evidence for anomalous long-ranged like-charged attractions induced by geometric confinement inspired a burst of activity. This has largely subsided because of nagging doubts regarding the experiments' reliability and interpretation. We describe a new class of thermodynamically self-consistent colloidal interaction measurements that confirm the appearance of pairwise attractions among colloidal spheres confined by one or two bounding walls. In addition to supporting previous claims for this as-yet unexplained effect, these measurements also cast new light on its mechanism.

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David G. Grier, Yilong Han. 2004-04-13. Anomalous interactions in confined charge-stabilized colloid. https://doi.org/10.1088/0953-8984%2F16%2F38%2F028

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