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Register a new userBound Pairs: Direct Evidence for Long-range Attraction between Like-Charged Colloids
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Added by
Butchi V. R. Tata Dr.
Publication date
2007
fields
Physics
and research's language is
English
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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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