Correct scaling of the correlation length from a theory for concentrated electrolytes

TL;DR

This paper develops a self-consistent theory for concentrated electrolytes, accurately predicting the scaling of correlation lengths and revealing their dependence on local charge density variance.

Contribution

It introduces a novel theoretical framework that explains the scaling behavior of correlation lengths in concentrated electrolytes, aligning with experimental observations.

Findings

Charge-charge correlations decay oscillatory with a specific length scale.

Density-density correlations decay monotonically with a similar length scale.

Correlation lengths depend critically on local charge density variance.

Abstract

Self-consistent theory for concentrated electrolytes is developed. Oscillatory decay of the charge-charge correlation function with the decay length that shows perfect agreement with the experimentally discovered and so far unexplained scaling is obtained. For the density-density correlations, monotonic asymptotic decay with the decay length comparable with the decay length of the charge correlations is found. We show that the correlation lengths in concentrated electrolytes depend crucially on the local variance of the charge density.