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Two-body polyelectrolyte mediated bridging interactions

Rudi Podgornik
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Abstract

We investigate theoretically polyelectrolyte bridging interactions on the two-body level. The model system is composed of two macroions with two oppositely charged flexible chains. The electrostatic interactions are treated on the Debye - H\" uckel level. The formal level of the theory is provided by the Feynman-Kleinert variational method generalized to include also self-interactions between polyelectrolyte segments. The variational equations are shown to exhibit two solution branches corresponding to {\sl strong} and {\sl weak} coupling, whereas conformations of the chain can be described as {\sl weakly} or {\sl strongly paired}. We investigate the effective pair interaction between the macroions in the parameter space and comment on the relevance of the calculation for bridging interactions in experimental context.

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Rudi Podgornik. 2003-07-10. Two-body polyelectrolyte mediated bridging interactions. https://doi.org/10.1063/1.1570400

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