Temperature-dependent dynamic disproportionation in LiNiO2
Nickelate materials offer diverse functionalities for energy and computing applications. Lithium nickel oxide (LiNiO<sub>2</sub>) is an archetypal layered nickelate, but the electronic structure of this correlated material is not yet fully understood. Here we investigate the temperature-dependent speciation and spin dynamics of Ni ions in LiNiO<sub>2</sub>. Ab initio simulations predict that Ni ions disproportionate into three states, which dynamically interconvert and whose populations vary with temperature. These predictions are verified using x-ray absorption spectroscopy, x-ray magnetic circular dichroism, and resonant inelastic x-ray scattering at the Ni L<sub>3,2</sub>-edge. Charge-transfer multiplet calculations consistent with disproportionation reproduce all experimental features. Our results support a model of dynamic disproportionation that explains diverse physical observations of LiNiO<sub>2</sub>, including magnetometry, thermally activated electronic conduction, diffractometry, core-level spectroscopies, and the stability of ubiquitous antisite defects. This unified understanding of the material properties of LiNiO<sub>2</sub> is important for applications of nickelate materials as battery cathodes, catalysts, and superconductors.
Authors
- Lijin An
- Peter Bencok (ORCID: https://orcid.org/0000-0002-6515-6706)
- Andrey D. Poletayev (ORCID: https://orcid.org/0000-0002-7892-8963)
- Robert S. Weatherup (ORCID: https://orcid.org/0000-0002-3993-9045)
- Robert A. House (ORCID: https://orcid.org/0000-0002-7415-477X)
- Robert J. Green (ORCID: https://orcid.org/0000-0003-1849-1576)
- Leanne A. H. Jones (ORCID: https://orcid.org/0000-0002-4654-3882)
- Grant Harris
- Ronny Sutarto (ORCID: https://orcid.org/0000-0002-1969-3690)
- Jack E. N. Swallow
- Benjamin J. Morgan (ORCID: https://orcid.org/0000-0002-3056-8233)
- Jonathon Cottom (ORCID: https://orcid.org/0000-0002-5918-9464)
- M. Saiful Islam (ORCID: https://orcid.org/0000-0003-0373-116X)
Institutions
- University of British Columbia (CA)
- Diamond Light Source (GB)
- University of Saskatchewan (CA)
- University of Oxford (GB)
- MRC Weatherall Institute of Molecular Medicine (GB)
- Advanced Research Center for Nanolithography (Netherlands) (NL)
- The Faraday Institution (GB)
- University of Bath (GB)
- Canadian Light Source (Canada) (CA)
- Bath Spa University (GB)
Publication Details
- Journal
- Nature Communications
- Published
- 2025-10-23
- DOI
- https://doi.org/10.1038/s41467-025-64429-4
- Primary Topic
- Advanced Condensed Matter Physics
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Canadian Light Source
- Diamond Light Source
- UK Research and Innovation
- Royal Academy of Engineering
- European Commission
- Canadian Institutes of Health Research
- Natural Sciences and Engineering Research Council of Canada