Ground-state correlation energy of counterions at a charged planar wall: Gibbs-Bogoliubov lower-bound approach

Hiroshi Frusawa

doi:10.1016/j.physleta.2020.126512

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arXiv · 2004.09994

Ground-state correlation energy of counterions at a charged planar wall: Gibbs-Bogoliubov lower-bound approach

Hiroshi Frusawa

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Abstract

Recent simulation results imply the lowering of the ground-state correlation energy per counterion at a charged planar wall, compared with that of the 2D and 3D one-component plasma systems. Our aim is to correctly evaluate the ground-state energy of strongly-coupled counterion systems by considering a quasi-2D bound state where bound counterions are confined to a layer of molecular thickness. We use a variational approach based on the Gibbs-Bogoliubov inequality for the lower-bound free energy so that the liquid-state theory can be incorporated into the formulations. The soft mean spherical approximation demonstrates that the lowered ground-state energy can be reproduced by the obtained analytical form of a quasi-2D bound state.

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Hiroshi Frusawa. 2020-05-08. Ground-state correlation energy of counterions at a charged planar wall: Gibbs-Bogoliubov lower-bound approach. https://doi.org/10.1016/j.physleta.2020.126512

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