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arXiv · 2410.06891

On the oxygen $p$ states in superconducting nickelates

Frank Lechermann
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Abstract

While key attention in transition-metal oxides is usually devoted to the $d$ states of the transition-metal ion, the O$(2p)$ states usually also carry important physics. We here examine these $p$ states in representatives of the novel superconducting nickelates, as described in realistic dynamical mean-field theory. Since the materials are located on the boundary between Mott-Hubbard and charge-transfer systems, the role of oxygen is expectedly subtle. Strong reduction of doped holes on oxygen and first asymmetry effects are featured in infinite-layer nickelates. A pronounced nature of bridging $p_z$ orbitals is identified in the La$_3$Ni$_2$O$_7$ system.

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Frank Lechermann. 2024-10-09. On the oxygen $p$ states in superconducting nickelates. https://doi.org/10.34734/fzj-2025-01965

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