The concentrations of electrolytes in charged cylindrical pores: The hydrostatic hypernetted chain/mean spherical approximation

The zeroth order (hydrostatic) approximation for inhomogeneous system is applied in the hypernetted chain/mean spherical (HNC/MSA) equations for charged cylindrical pores. The derived equations are introduced as hydrostatic hypernetted chain/mean spherical approximation (HHNC/MSA). These equations are solved using the collocation version of the finite element method. Equilibrium density profiles and mean electrostatic potential profiles are presented and compared with the results of HNC/MSA equations. Density profiles and Exclusion coefficient profiles for 1:1 and 1:2 electrolytes are also compared with the grand canonical Monte Carlo (GCMC) data. Good agreement between the present calculations and GCMC data are observed. Quantitative differences between the present calculations and HNC/MSA are found which are especially significant for large pore diameters and high electrolyte concentrations.