Conductance of concentrated electrolytes: multivalency and the Wien effect

Yael Avni; David Andelman; Henri Orland

doi:10.1063/5.0111645

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arXiv · 2207.10116

Conductance of concentrated electrolytes: multivalency and the Wien effect

Yael Avni·David Andelman·Henri Orland

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Abstract

The electric conductivity of ionic solutions is well understood at low ionic concentrations of up to a few millimolar but becomes difficult to unravel at higher concentrations that are still common in nature and technological applications. A model for the conductivity at high concentrations was recently put forth for monovalent electrolytes at low electric fields. The model relies on applying a stochastic density-functional theory and using a modified electrostatic pair-potential that suppresses unphysical, short-range electrostatic interactions. Here, we extend the theory to multivalent ions as well as to high electric fields where a deviation from Ohm's law known as the Wien effect occurs. Our results are in good agreement with experiments and recent simulations.

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Yael Avni, David Andelman, Henri Orland. 2022-09-29. Conductance of concentrated electrolytes: multivalency and the Wien effect. https://doi.org/10.1063/5.0111645

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