Journal of Chemical Physics, Vol.118, No.24, 11286-11296, 2003
Two-body polyelectrolyte-mediated bridging interactions
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-Huckel 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 strong and weak coupling, whereas conformations of the chain can be described as weakly or 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. (C) 2003 American Institute of Physics.