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arXiv · cond-mat/9803258

Steric Effects in Electrolytes: A Modified Poisson-Boltzmann Equation

I. Borukhov·D. Andelman·H. Orland
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Abstract

The adsorption of large ions from solution to a charged surface is investigated theoretically. A generalized Poisson--Boltzmann equation, which takes into account the finite size of the ions is presented. We obtain analytical expressions for the electrostatic potential and ion concentrations at the surface, leading to a modified Grahame equation. At high surface charge densities the ionic concentration saturates to its maximum value. Our results are in agreement with recent experiments.

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I. Borukhov, D. Andelman, H. Orland. 1998-03-21. Steric Effects in Electrolytes: A Modified Poisson-Boltzmann Equation. https://doi.org/10.1103/physrevlett.79.435

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