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A physical method for deriving the electrostatic interaction between rod-like polyions at all mutual angles.

S L Brenner·V A Parsegian
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Abstract

The screened Coulomb interaction between polyelectrolyte cylinders immersed in an ionic bath is examined. The electrostatic force and torque acting between a pair of unlike rods is formulated for all separations in which the electrostatic potential on some dividing surface between rods can be written as a linear superposition of isolated cylinder potentials. (The surface potential on the rods themselves may be much higher than that permitted by a superposition approximation.) The mutual energy in the case of skewed rods is found to be exponential in separation and proportional to 1/sin theta where theta is the twist angle of one rod relative to the other. Rods with similar charge repel each other with a torque acting to make the rods perpendicular while rods of opposite charge attract with the parallel arrangement preferred.

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BibTeXRIS

S L Brenner, V A Parsegian. 1974. A physical method for deriving the electrostatic interaction between rod-like polyions at all mutual angles.. https://doi.org/10.1016/s0006-3495(74)85919-9

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