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arXiv · 1102.4229

Asymptotics for Two-dimensional Atoms

Phan Thanh Nam·Fabian Portmann·Jan Philip Solovej
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Abstract

We prove that the ground state energy of an atom confined to two dimensions with an infinitely heavy nucleus of charge $Z>0$ and $N$ quantum electrons of charge -1 is $E(N,Z)=-{1/2}Z^2\ln Z+(E^{\TF}(λ)+{1/2}c^{\rm H})Z^2+o(Z^2)$ when $Z\to \infty$ and $N/Z\to λ$, where $E^{\TF}(λ)$ is given by a Thomas-Fermi type variational problem and $c^{\rm H}\approx -2.2339$ is an explicit constant. We also show that the radius of a two-dimensional neutral atom is unbounded when $Z\to \infty$, which is contrary to the expected behavior of three-dimensional atoms.

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Phan Thanh Nam, Fabian Portmann, Jan Philip Solovej. 2011-06-16. Asymptotics for Two-dimensional Atoms. https://arxiv.org/abs/1102.4229

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