Electrostatic potential around charged finite rodlike macromolecules: nonlinear Poisson-Boltzmann theory.
In this paper, we show that the far field electrostatic potential created by a highly charged finite size cylinder within the nonlinear Poisson-Boltzmann (PB) theory, is remarkably close to the potential created within the linearized PB approximation by the same object at a well-chosen fixed potential. Comparing the nonlinear electrostatic potential with its linear counterpart associated to a fixed potential boundary condition (called the effective surface potential), we deduce the effective charge of the highly charged cylinder. Values of the effective surface potential are provided as a function of the bare surface charge and Debye length of the ionic solution. This allows to compute the anisotropic electrostatic interaction energy of two distant finite rods.
Chapot
David
D
Laboratoire de Physique de l'E.N.S. de Lyon, UMR CNRS 5672, 46 Allée d'Italie, 69364 Lyon Cedex, France.
Bocquet
Lydéric
L
Trizac
Emmanuel
E