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Conformation of a Polyelectrolyte Complexed to a Like-Charged Colloid

Rene Messina·Christian Holm·Kurt Kremer
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Abstract

We report results from a molecular dynamics (MD) simulation on the conformations of a long flexible polyelectrolyte complexed to a charged sphere, \textit{both negatively charged}, in the presence of neutralizing counterions in the strong Coulomb coupling regime. The structure of this complex is very sensitive to the charge density of the polyelectrolyte. For a fully charged polyelectrolyte the polymer forms a dense two-dimensional "disk", whereas for a partially charged polyelectrolyte the monomers are spread over the colloidal surface. A mechanism involving the \textit{overcharging} of the polyelectrolyte by counterions is proposed to explain the observed conformations.

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Rene Messina, Christian Holm, Kurt Kremer. 2001-11-19. Conformation of a Polyelectrolyte Complexed to a Like-Charged Colloid. https://doi.org/10.1103/physreve.65.041805

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