title: Solvation effects on like-charge attraction.
abstract: We present results of molecular dynamics simulations of the electrostatic interaction between two parallel charged rods in the presence of divalent counterions. Such polyelectrolytes have been considered as a simple model for understanding electrostatic interactions in highly charged biomolecules such as DNA. Since there are correlations between the free charge carriers, the phenomenon of like charge attraction appears for specific parameters. We explore the role of solvation effects and the resulting deviations from Coulomb's law on the nanoscale on this peculiar phenomenon. The behavior of the force between the charged rods in a simulation with atomistic representation of water molecules is completely different from a model in which water is modeled as a continuum dielectric. By calculating counterion-rodion pair correlation functions, we find that the presence of water molecules changes the structure of the counterion cloud and results in both qualitative and quantitative changes of the force between highly charged polyelectrolytes.
authors: Department of Physics and Astronomy, The University of British Columbia, 6224 Agricultural Road, Vancouver, British Columbia V6T 1Z4, Canada.
authors: Shahzad
authors: S
authors: Ghanbarian
authors: Jörg
authors: J
authors: Rottler
mesh_terms: D055595:Mechanical Phenomena; D008968:Molecular Conformation; D056004:Molecular Dynamics Simulation; D011108:Polymers / Q000737:chemistry; D012997:Solvents / Q000737:chemistry*; D055672:Static Electricity
chemical_list: D011108:Polymers; D012997:Solvents