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arXiv · cond-mat/0310540

Distribution of counterions near discretely charged planes and rods

Mark L. Henle·Christian D. Santangelo·Deena M. Patel·Philip A. Pincus
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Abstract

Realistic charged macromolecules are characterized by discrete (rather than homogeneous) charge distributions. We investigate the effects of surface charge discretization on the counterion distribution at the level of mean-field theory using a two-state model. Both planar and cylindrical geometries are considered; for the latter case, we compare our results to numerical solutions of the full Poisson-Boltzmann equation. We find that the discretization of the surface charge can cause enhanced localization of the counterions near the surface; for charged cylinders, counterion condensation can exceed Oosawa-Manning condensation.

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Mark L. Henle, Christian D. Santangelo, Deena M. Patel, Philip A. Pincus. 2004-04-30. Distribution of counterions near discretely charged planes and rods. https://doi.org/10.1209/epl%2Fi2003-10205-1

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