Issue 20, 2018

Strong-coupling theory of counterions between symmetrically charged walls: from crystal to fluid phases

Abstract

We study thermal equilibrium of classical pointlike counterions confined between symmetrically charged walls at distance d. At very large couplings when the counterion system is in its crystal phase, a harmonic expansion of particle deviations is made around the bilayer positions, with a free lattice parameter determined from a variational approach. For each of the two walls, the harmonic expansion implies an effective one-body potential at the root of all observables of interest in our Wigner strong-coupling expansion. Analytical results for the particle density profile and the pressure are in good agreement with numerical Monte Carlo data, for small as well as intermediate values of d comparable with the Wigner lattice spacing. While the strong-coupling theory is extended to the fluid regime by using the concept of a correlation hole, the Wigner calculations appear trustworthy for all electrostatic couplings investigated. Our results significantly extend the range of accuracy of analytical equations of state for strongly interacting charged planar interfaces.

Graphical abstract: Strong-coupling theory of counterions between symmetrically charged walls: from crystal to fluid phases

Supplementary files

Article information

Article type
Paper
Submitted
19 Mar 2018
Accepted
16 Apr 2018
First published
25 Apr 2018

Soft Matter, 2018,14, 4040-4052

Strong-coupling theory of counterions between symmetrically charged walls: from crystal to fluid phases

L. Šamaj, M. Trulsson and E. Trizac, Soft Matter, 2018, 14, 4040 DOI: 10.1039/C8SM00571K

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements