Theory of inhomogeneous rod-like Coulomb fluids

Rudolf Podgornik

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arXiv · 2012.06172

Theory of inhomogeneous rod-like Coulomb fluids

Rudolf Podgornik

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Abstract

A field theoretic representation of the classical partition function is derived for a system composed of a mixture of anisotropic and isotropic mobile charges that interact {\sl via} long range Coulomb and short range nematic interactions. The field theory is then solved on a saddle-point approximation level, leading to a coupled system of Poisson-Boltzmann and Maier-Saupe equations. Explicit solutions are finally obtained for a rod-like counterion-only system in proximity of a charged planar wall, generalizing the standard Gouy-Chapman results. The nematic order parameter profile, the counterion density profile and the electrostatic potential profile are interpreted within the framework of a nematic wetting layer with a (Donnan) potential difference.

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Rudolf Podgornik. 2020-12-11. Theory of inhomogeneous rod-like Coulomb fluids. https://arxiv.org/abs/2012.06172

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