Jahn-Teller distortion, octahedra rotations and orbital ordering in perovskites : KScF
© 2024 Wiley Periodicals LLC.
| Publié dans: | Journal of computational chemistry. - 1984. - 45(2024), 14 vom: 30. Mai, Seite 1067-1077 |
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| Auteur principal: | |
| Autres auteurs: | , , |
| Format: | Article en ligne |
| Langue: | English |
| Publié: |
2024
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| Accès à la collection: | Journal of computational chemistry |
| Sujets: | Journal Article Jahn‐Teller deformation KScF density functional calculation magnetic ordering octahedra rotation orbital ordering phase transition |
| Résumé: | © 2024 Wiley Periodicals LLC. The KScF 3 perovskite has been used as a model for investigating the relative importance of the Jahn-Teller (JT) lift of degeneracy, the ScF 6 octahedra rotation (OR), and the quadrupole-quadrupole interaction linked to different occupancy of the Sc t 2 g subshell in various sites of the unit cell (orbital ordering, OO). The group-subgroup sequence P m 3 ¯ m , P 4 m m m , P 4 m b m , and P n m a , supplemented by C m m m and I 4 m c m , has been explored by using an all electron Gaussian type basis set, hybrid functionals, and the CRYSTAL17 code. The JT lift of degeneracy provides a stabilization about 5 times larger than the sum of the OO and OR effects. The energy gained in the transition from P 4 m m m to P 4 m b m , consisting in a rotation of the octahedra around the c axis, is 1077 μ E h . From P 4 m b m to P n m a , additional rotations around the a and b axes are possible, and the d Sc electron can occupy a different t 2 g orbital, with a total energy reduction of 2318 μ E h . The rotation of the octahedra reduces the strength of superexchange: in going from P 4 m m m to P n m a the G-AFM stabilization with respect to FM shrinks by a factor 4 |
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| Description: | Date Revised 12.04.2024 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
| ISSN: | 1096-987X |
| DOI: | 10.1002/jcc.27306 |