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arXiv · 1606.02095

Mechanism of chain collapse of strongly charged polyelectrolytes

Anvy Moly Tom·Satyavani Vemparala·R. Rajesh·Nikolai V. Brilliantov
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Abstract

We perform extensive molecular dynamics simulations of a charged polymer in a good solvent in the regime where the chain is collapsed. We analyze the dependence of the gyration radius $R_g $ on the reduced Bjerrum length $\ell_B$ and find two different regimes. In the first one, called as a weak electrostatic regime, $R_g \sim \ell_B^{-1/2}$, which is consistent only with the predictions of the counterion-fluctuation theory. In the second one, called a strong electrostatic regime, we find $R_g \sim \ell_B^{-1/5}$. To explain the novel regime we modify the counterion-fluctuation theory.

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Anvy Moly Tom, Satyavani Vemparala, R. Rajesh, Nikolai V. Brilliantov. 2016-06-07. Mechanism of chain collapse of strongly charged polyelectrolytes. https://doi.org/10.1103/physrevlett.117.147801

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