Counterion-Mediated Weak and Strong Coupling Electrostatic Interaction between Like-Charged Cylindrical Dielectrics

TL;DR

This paper investigates how dielectric mismatch and counterion valency influence electrostatic interactions between like-charged cylinders, using theoretical analysis and Monte Carlo simulations to explore weak and strong coupling regimes.

Contribution

It introduces a detailed analysis of counterion-mediated interactions considering dielectric effects and compares weak and strong coupling limits with simulation results.

Findings

Dielectric mismatch induces image charges affecting interactions.

Weak and strong coupling regimes show distinct interaction behaviors.

Simulations confirm theoretical predictions in respective regimes.

Abstract

We examine the effective counterion-mediated electrostatic interaction between two like-charged dielectric cylinders immersed in a continuous dielectric medium containing neutralizing mobile counterions. We focus on the effects of image charges induced as a result of the dielectric mismatch between the cylindrical cores and the surrounding dielectric medium and investigate the counterion-mediated electrostatic interaction between the cylinders in both limits of weak and strong electrostatic couplings (corresponding, e.g., to systems with monovalent and multivalent counterions, respectively). The results are compared with extensive Monte-Carlo simulations exhibiting good agreement with the limiting weak and strong coupling results in their respective regime of validity.