Eur. Phys. J. Special Topics 216, 95-105 (2013)
https://doi.org/10.1140/epjst/e2013-01732-4

Regular Article

On thermodynamics and mobility of ions enclosed within charged nanoporous system

¹ University of Ljubljana, Faculty of Chemistry and Chemical Technology, Aškerčeva 5, 1001 Ljubljana, Slovenia
² UPMC Univ. Paris 06, UMR 7195, PECSA, 75005 Paris, France

^a e-mail: vojko.vlachy@fkkt.uni-lj.si

Received: 30 November 2012
Revised: 6 December 2012
Published online: 31 January 2013

Abstract

New simulations and integral equation results are presented for a model partly quenched system composed of monovalent ions. Static and dynamic properties of the system are explored using the replica Ornstein–Zernike theory in the hypernetted chain approximation and Brownian dynamic simulations. The model system consists of two subsystems: one is a collection of charged obstacles (matrix), and the other is an invading electrolyte. The overall system is electroneutral, while the subsystems are not. Charged species are represented by Lennard–Jones spheres of equal size, with either positive or negative charge in the center. The solvent is treated as a continuous dielectric. The purpose of this study is to correlate the mobility of ions (self-diffusion coefficients) with their individual activity coefficients. In addition, the effects of the matrix preparation and of the conditions of observation (dielectric constant of solvent, temperature) are investigated. For the first time, the effect of the charged obstacles on the excess internal energy of the electrolyte solution is also examined.