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Attractions between charged colloidal spheres mediated by correlated absorbed ions

190   0   0.0 ( 0 )
 Added by Francisco J. Solis
 Publication date 2000
  fields Physics
and research's language is English




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We describe arrangements of ions capable of producing short-range attractive interactions between pairs of charged colloidal spheres in the low temperature strongly correlated limit. For particles of radius $R$ with bare charge $Z$ and comparable absorbed charge $-N$ ($N sim Z$), the correlations contribution to the spheres self-energy scales as $N^{3/2}/R$, and as $N/R$ for the interaction energy between two touching spheres. We show that the re-arrangement of charges due to polarization plays an insignificant role in the nature and magnitude of the interaction.

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