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Computing Counterion Densities at Intermediate Coupling

Christian D. Santangelo
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Abstract

By decomposing the Coulomb interaction into a long distance component appropriate for mean-field theory, and a nonmean-field short distance component, we compute the counterion density near a charged surface for all values of the counterion coupling parameter. A modified strong-coupling expansion that is manifestly finite at all coupling strengths is used to treat the short distance component. We find a nonperturbative correction related to the lateral counterion correlations that modifies the density at intermediate coupling.

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Christian D. Santangelo. 2005-01-20. Computing Counterion Densities at Intermediate Coupling. https://doi.org/10.1103/physreve.73.041512

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