Solving the Poisson-Boltzmann equation to obtain interaction energies between confined, like-charged cylinders

We numerically solve the nonlinear Poisson-Boltzmann equation for two cylinders confined by two parallel charged plates. The repulsive electrical double layer component of the cylinder pair potential is substantially reduced by confinement between like-charged plates. While the effective cylinder surface charge is increased by the confinement, the effective interaction screening length is reduced, this effect being dominant so that the repulsive confined cylinder-cylinder interaction potential is reduced. (C) 1998 American Institute of Physics. [S0021-9606(98)50144-4].