Anomalous bending of a polyelectrolyte
Abstract
We report on a study of the shape of a stiff, charged rod that is subjected to equal and opposite force couples at its two ends. Unlike a neutral elastic rod, which forms a constant curvature configuration under such influences, the charged rod tends to flatten in the interior and accumulate the curvature in the end points, to maximally reduce the electrostatic self-repulsion. The effect of this nonuniform bending on the effective elasticity and on the statistical conformations of a fluctuating charged rod is discussed. An alternative definition for the electrostatic persistence length is suggested. This new definition is found to be consistent with a corresponding length that can be deduced from the end-to-end distribution function of a fluctuating polyelectrolyte.
Cite
@article{arxiv.cond-mat/0208178,
title = {Anomalous bending of a polyelectrolyte},
author = {Roya Zandi and Joseph Rudnick and Ramin Golestanian},
journal= {arXiv preprint arXiv:cond-mat/0208178},
year = {2009}
}
Comments
RevTeX 4, 10 pages, 11 eps figures