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arXiv · 2511.22927

Two-Electron Correlations in the Metallic Electron Gas

Zhiyi Li·Pengcheng Hou·Bao-Zong Wang·Youjin Deng·Kun Chen
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Abstract

We present high-precision \emph{ab initio} calculations of the four-point vertex function for the three-dimensional uniform electron gas using variational diagrammatic Monte Carlo. From these results, we extract Landau parameters that reveal a density-driven crossover from underscreening to overscreening, and obtain the full two-electron scattering amplitude on the Fermi surface with controlled accuracy. A residual analysis of the scattering amplitude against the charge-channel Kukkonen--Overhauser (KO$^+$) interaction shows that only a minimal s-wave correction in the antiparallel-spin channel is needed, defining the sKO$^+$ ansatz: KO$^+$ within the local-density approximation plus this short-range correction. Using both our direct VDMC amplitudes and the sKO$^+$ ansatz, we compute the electron-electron contribution to the thermal resistivity, obtaining quantitative agreement with experiments on simple metals (Al, Na, K, Rb). sKO$^+$ thus provides a controlled UEG-based effective interaction for simple-metal transport and future first-principles extensions.

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Zhiyi Li, Pengcheng Hou, Bao-Zong Wang, Youjin Deng, Kun Chen. 2025-11-28. Two-Electron Correlations in the Metallic Electron Gas. https://arxiv.org/abs/2511.22927

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