Anomalous interactions in confined charge-stabilized colloid
نویسندگان
چکیده
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 asyet unexplained effect, these measurements also cast new light on its mechanism. PACS numbers: 82.70.Dd,05.40.-a,61.20.p
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