Distribution of charge particles confined between three interfacial surfaces

We present a model of a charged membrane where the charge density is distributed in a region of thickness d(m). The model consists of three flat regions having the same dielectric constant were charged particles can be distributed with cylindrical symmetry. The concentration profile of particles and their pair correlation functions were calculated for various parameters of the model (distance and charge density). The particles profiles, at the limit of large distances and small charge densities, are equal to those found in the solution of the Poisson-Boltzmann equation. For high charge density, the contact profiles show a significant structure, and they are different to those found by the Poisson-Boltzmann solution and for a model of stiff membranes. These results indicate that a model of membrane with thickness d(m) (internal structure) may be necessary to study the effects of pressure between the surfaces.