Mechanism of Chain Collapse of Strongly Charged Polyelectrolytes.

Phys Rev Lett

Department of Mathematics, University of Leicester, Leicester LE1 7RH, United Kingdom.

Published: September 2016

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 ℓ_{B} and find two different regimes. In the first one, called a weak electrostatic regime, R_{g}∼ℓ_{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}∼ℓ_{B}^{-1/5}. To explain the novel regime we modify the counterion-fluctuation theory.

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http://dx.doi.org/10.1103/PhysRevLett.117.147801DOI Listing

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