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arXiv · 1201.6081

The Dielectric Constant of Ionic Solutions: A Field-Theory Approach

Amir Levy·David Andelman·Henri Orland
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Abstract

We study the variation of the dielectric response of a dielectric liquid (e.g. water) when a salt is added to the solution. Employing field-theoretical methods we expand the Gibbs free-energy to first order in a loop expansion and calculate self-consistently the dielectric constant. We predict analytically the dielectric decrement which depends on the ionic strength in a complex way. Furthermore, a qualitative description of the hydration shell is found and is characterized by a single length scale. Our prediction fits rather well a large range of concentrations for different salts using only one fit parameter related to the size of ions and dipoles.

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Amir Levy, David Andelman, Henri Orland. 2012-01-29. The Dielectric Constant of Ionic Solutions: A Field-Theory Approach. https://doi.org/10.1103/physrevlett.108.227801

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