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Kondo--lattice-like effects of hydrogen in transition metals

R. Eder·H. F. Pen·G. A. Sawatzky
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Abstract

We discuss the possibility of a Kondo like effect associated with H in metals resulting from the strong dependence of the H1s orbital radius on the occupation number. We demonstrate that such a strong breathing property of the orbital radius, which translates directly into a strong occupation dependent hopping, results in the formation of local singlet-like bound states involving one electron on H and one on the surrounding metal orbitals. We also show that already at a mean field level an occupation dependent hopping integral leads to a substantial potential energy correction on hydrogen, and that the failure of LDA to incorporate this correction is probably responsible for the incorrect prediction of a metallic ground state for the YH3 switchable mirror compounds.

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R. Eder, H. F. Pen, G. A. Sawatzky. 1997-04-09. Kondo--lattice-like effects of hydrogen in transition metals. https://doi.org/10.1103/physrevb.56.10115

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