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Abstract Lanthanides in the trivalent oxidation state are typically described using an ionic picture that leads to localized magnetic moments. The hierarchical energy scales associated with trivalent lanthanides produce desirable properties for e.g., molecular magnetism, quantum materials, and quantum transduction. Here, we show that this traditional ionic paradigm breaks down for praseodymium in the tetravalent oxidation state. Synthetic, spectroscopic, and theoretical tools deployed on several solid-state Pr 4+ -oxides uncover the unusual participation of 4 f orbitals in bonding and the anomalous hybridization of the 4 f 1 configuration with ligand valence electrons, analogous to transition metals. The competition between crystal-field and spin-orbit-coupling interactions fundamentally transforms the spin-orbital magnetism of Pr 4+ , which departs from the J eff = 1/2 limit and resembles that of high-valent actinides. Our results show that Pr 4+ ions are in a class on their own, where the hierarchy of single-ion energy scales can be tailored to explore new correlated phenomena in quantum materials.
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Transduction between magnets and ions
A time-varying magnetic field generates an electric field in an ionic conductor, causing ions to move and inducing an ionic current. This magnetoionic transduction enables ionotronic transformers for signal transduction between electrons and ions.
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- Award ID(s):
- 2011754
- PAR ID:
- 10499971
- Publisher / Repository:
- Royal Society of Chemistry
- Date Published:
- Journal Name:
- Materials Horizons
- Volume:
- 8
- Issue:
- 7
- ISSN:
- 2051-6347
- Page Range / eLocation ID:
- 1959 to 1965
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1039/D1MH00418B
