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Charge-Fluctuation-Induced Non-analytic Bending Rigidity

A. W. C. Lau·P. Pincus
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Abstract

In this Letter, we consider a neutral system of mobile positive and negative charges confined on the surface of curved films. This may be an appropriate model for: i) a highly charged membrane whose counterions are confined to a sheath near its surface; ii) a membrane composed of an equimolar mixture of anionic and cationic surfactants in aqueous solution. We find that the charge fluctuations contribute a non-analytic term to the bending rigidity that varies logarithmically with the radius of curvature. This may lead to spontaneous vesicle formation, which is indeed observed in similar systems.

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A. W. C. Lau, P. Pincus. 1998-01-28. Charge-Fluctuation-Induced Non-analytic Bending Rigidity. https://doi.org/10.1103/physrevlett.81.1338

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