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arXiv · 2005.10580

Screened Coulomb interactions of general macroions with nonzero particle volume

Jeffrey C. Everts
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Abstract

A semianalytical approach is developed to calculate the effective pair potential of rigid arbitrarily shaped macroions with a nonvanishing particle volume, valid within linear screening theory and the mean-field approximation. The essential ingredient for this framework is a mapping of the particle to a singular charge distribution with adjustable effective charge and shape parameters determined by the particle surface electrostatic potential. For charged spheres this method reproduces the well-known Derjaguin-Landau-Verwey-Overbeek (DLVO) potential. Further exemplary benchmarks of the method for more complicated cases, like tori, triaxial ellipsoids, and additive torus-sphere mixtures, leads to accurate closed-form integral expressions for all particle separations and orientations. The findings are relevant for determining the phase behaviour of macroions with experiments and simulations for various particle shapes.

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Jeffrey C. Everts. 2020-05-21. Screened Coulomb interactions of general macroions with nonzero particle volume. https://doi.org/10.1103/physrevresearch.2.033144

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