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

Department of Materials and Interfaces, Weizmann Institute - Rehovot 76100, Israel

Received: 27 May 2002
Accepted: 2 September 2002

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.