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arXiv · 2610.35896

Same-spin correlation screens the exchange peak of the electron gas near 2kF

Carl A. Kukkonen
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Abstract

Exchange alone gives the electron gas a local field factor with a sharp peak just below 2kF. Quantum Monte Carlo finds none. Both spin channels are computed here from their lowest diagrams with a dynamically screened interaction and no fitting. Parallel spin correlation is the negative image of exchange and removes about half the peak; the calculated spin-resolved factors account for the QMC data at rs = 1 and 2, and at q = 0 for the compressibility and spin susceptibility obtained from the ground-state energy. The two classes of diagrams are the two terms of the kernel of Hedin's vertex equation, of which the second is routinely dropped.

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Carl A. Kukkonen. 2026-10-29. Same-spin correlation screens the exchange peak of the electron gas near 2kF. https://arxiv.org/abs/2610.35896

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