Bound Pairs: Direct Evidence for Long-range Attraction between Like-Charged Colloids

B. V. R. Tata; P. S. Mohanty; M. C. Valsakumar

doi:10.1016/j.ssc.2008.06.026

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arXiv · 0711.2883

Bound Pairs: Direct Evidence for Long-range Attraction between Like-Charged Colloids

B. V. R. Tata·P. S. Mohanty·M. C. Valsakumar

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Abstract

We report observations of stable bound pairs in very dilute deionized aqueous suspensions of highly charged polystyrene colloidal particles, with monovalent counterions, using a confocal laser scanning microscope. Through an analysis of several thousands of time series of confocal images recorded deep inside the bulk suspension, we find that the measured pair-potential, U(r) has a long-range attractive component with well depths larger than the thermal energy. These observations provide a direct and unequivocal evidence for the existence of long-range attraction in U(r) of like-charged colloidal particles.

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B. V. R. Tata, P. S. Mohanty, M. C. Valsakumar. 2007-11-19. Bound Pairs: Direct Evidence for Long-range Attraction between Like-Charged Colloids. https://doi.org/10.1016/j.ssc.2008.06.026

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