Computing counterion densities at intermediate coupling.
By decomposing the Coulomb interaction into a long-distance component appropriate for mean-field theory, and a non-mean-field short distance component, we compute the counterion density near a charged surface for all values of the counterion coupling parameter. A modified strong-coupling expansion that is manifestly finite at all coupling strengths is used to treat the short-distance component. We find a nonperturbative correction related to the lateral counterion correlations that modifies the density at intermediate coupling.
Santangelo
Christian D
CD
Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, PA 19104, USA. santancd@physics.upenn.edu