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arXiv · 1102.4918

Determination of the zeta potential for highly charged colloidal suspensions

Giovanni Giupponi·Ignacio Pagonabarraga
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Abstract

We compute the electrostatic potential at the surface, or zeta potential $ζ$, of a charged particle embedded in a colloidal suspension using a hybrid mesoscopic model. We show that for weakly perturbing electric fields, the value of $ζ$ obtained at steady state during electrophoresis is statistically indistinguishable from $ζ$ in thermodynamic equilibrium. We quantify the effect of counterions concentration on $ζ$. We also evaluate the relevance of the lattice resolution for the calculation of $ζ$ and discuss how to identify the effective electrostatic radius.

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Giovanni Giupponi, Ignacio Pagonabarraga. 2011-02-24. Determination of the zeta potential for highly charged colloidal suspensions. https://doi.org/10.1098/rsta.2011.0024

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