The structure of electrolytes in cylindrical pores

Abstract

The hypernetted chain/mean-spherical approximation (HNC/MSA) equations are derived for ion distributions within and surrounding a charged cylindrical pore for the restricted primitive model of electrolytes. The equilibrium density profiles, mean electrostatic potential profiles, as well as other electrical double-layer structural parameters are presented and compared with the results of the Poisson–Boltzmann (PB) equation and with grand Canonical Monte Carlo data. Quantitative and qualitative differences between the HNC/MSA and the PB theories are found which are especially large for small pore diameters. The effect of geometry is investigated through a comparison with HNC/MSA results for electrolyte confined within a slit pore formed by two parallel plates of infinite extension.