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arXiv · 0909.4586

Valence Fluctuations and Quasiparticle Multiplets in Pu Chalcogenides and Pnictides

Chuck-Hou Yee·Gabriel Kotliar·Kristjan Haule
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Abstract

The spectra of Pu chalcogenides and pnictides are computed with LDA+DMFT and interpreted with the aid of valence histograms and slave-boson calculations. We find the chalcogenides are mixed-valent ($n_f = 5.2$) materials with a strongly $T$-dependent low-energy density of states and a triplet of quasiparticle peaks below the Fermi level. Furthermore, we predict a doublet of reflected peaks above the Fermi level. In the pnictides, the raising of $f^6$ states relative to $f^5$ suppresses valence fluctuations, resulting in integral-valent ($n_f = 5.0$) local moment metals.

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Chuck-Hou Yee, Gabriel Kotliar, Kristjan Haule. 2009-09-25. Valence Fluctuations and Quasiparticle Multiplets in Pu Chalcogenides and Pnictides. https://doi.org/10.1103/physrevb.81.035105

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