  We applied the mean-field approach to a columnar bundle assembled by the
parallel arrangement of stiff polyelectrolyte rods in a salt bath. The
electrostatic potential can be divided into two regions: inside the bundle for
condensed counter-ions, and outside the bundle for free small ions. To
determine the distribution of condensed counter-ions inside the bundle, we use
a local self-consistent condition that depends on the charge density, the
electrostatic potential, and the net polarization. The results showed that,
upon bundle formation, the electric charge of polyelectrolytes, even those
inside the bundle, tend to survive in an inhomogeneous manner, and thus their
width remains finite under thermal equilibrium because of the long-range effect
of charge instability.
