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arXiv · 0907.3124

Ionic conductivity on a wetting surface

Brian Skinner·M. S. Loth·B. I. Shklovskii
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Abstract

Recent experiments measuring the electrical conductivity of DNA molecules highlight the need for a theoretical model of ion transport along a charged surface. Here we present a simple theory based on the idea of unbinding of ion pairs. The strong humidity dependence of conductivity is explained by the decrease in the electrostatic self-energy of a separated pair when a layer of water (with high dielectric constant) is adsorbed to the surface. We compare our prediction for conductivity to experiment, and discuss the limits of its applicability.

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Brian Skinner, M. S. Loth, B. I. Shklovskii. 2009-10-13. Ionic conductivity on a wetting surface. https://doi.org/10.1103/physreve.80.041925

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