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A density functional theory study of electric potential saturation: planar geometry

Gabriel Tellez·Emmanuel Trizac
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Abstract

We investigate the possibility of electrostatic potential saturation, which may lead to the phenomenon of effective charge saturation. The system under study is a uniformly charged infinite plane immersed in an arbitrary electrolyte made up of several micro-species. To describe the electric double layer, we use a generic density functional theory in which the local micro-ionic density profiles are arbitrary functions of the local electrostatic potential. A necessary and sufficient condition is obtained for saturation, whereby the electrostatic potential created by the plane becomes independent of its bare charge, provided the latter is large enough.

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Gabriel Tellez, Emmanuel Trizac. 2003-08-01. A density functional theory study of electric potential saturation: planar geometry. https://doi.org/10.1103/physreve.68.061401

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