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The on-top pair-correlation density in the homogeneous electron liquid

Zhixin Qian
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Abstract

The ladder theory, in which the Bethe-Goldstone equation for the effective potential between two scattering particles plays a central role, is well known for its satisfactory description of the short-range correlations in the homogeneous electron liquid. By solving exactly the Bethe-Goldstone equation in the limit of large transfer momentum between two scattering particles, we obtain accurate results for the on-top pair-correlation density $g(0)$, in both three dimensions and two dimensions. Furthermore, we prove, in general, the ladder theory satisfies the cusp condition for the pair-correlation density $g(r)$ at zero distance $r=0$.

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Zhixin Qian. 2005-09-07. The on-top pair-correlation density in the homogeneous electron liquid. https://doi.org/10.1103/physrevb.73.035106

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