Poisson-Boltzmann equation polyelectrolyte-counterion interactions

The polyelectrolyte chains exist in the effective medium created by the counterions and ions from the simple salt. The charges on the polymer chains interact among themselves mediated by the neutralizing plasma that makes up the system except the polymer molecules. We further assume that the mediation by the background is adequately described by the Debye-Hiickel theory. This assumption allows us to deduce the key features, without resorting to heavy numerical work that will be needed to solve the very complex Poisson-Boltzmann equations for such topologically correlated objects as flexible polymers. 

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