Article

# Flexible Polyelectrolytes with Monovalent Salt

(Impact Factor: 1.72). 07/2004; DOI: 10.1016/j.physa.2005.05.048
Source: arXiv

ABSTRACT We present a model for describing flexible polyelectrolytes in a good solvent a nd in the presence of monovalent salt . The molecule composed by $N$ monomers is characterized by the end to end distanc e $R_e=b (Z-1)^\gamma$ and the number of associated counterions $n$. At high tem peratures the polyelectrolyte behaves as a neutral polymer ($\gamma=0.588$). Dec reasing the temperature, the macromolecule changes from this extended configurat ion($\gamma=0.588$) to a stretched form ($\gamma\approx 1$). At even lower temp eratures, above the Manning condensation threshold, the polyelectrolyte collapse s ($\gamma\approx 0.3$). Our results show good agreement with simulations.

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