Universal reduction of pressure between charged surfaces by long-wavelength surface charge modulation

TL;DR

This paper predicts that long-wavelength surface charge modulations universally decrease the pressure between charged surfaces with counterions, due to enhanced counterion localization near the surfaces, confirmed by Monte Carlo simulations.

Contribution

Theoretical prediction of universal pressure reduction caused by long-wavelength surface charge modulations, supported by Monte Carlo simulations.

Findings

Surface charge modulations reduce pressure between charged surfaces.

Enhanced counterion localization near surfaces due to modulations.

Monte Carlo simulations confirm the theoretical prediction.

Abstract

We predict theoretically that long-wavelength surface charge modulations universally reduce the pressure between the charged surfaces with counterions compared with the case of uniformly charged surfaces with the same average surface charge density. The physical origin of this effect is the fact that surface charge modulations always lead to enhanced counterion localization near the surfaces, and hence, fewer charges at the midplane. We confirm the last prediction with Monte Carlo simulations.