Orthogonal magnetic structures of Fe4O5 : representation analysis and DFT calculations
(2023) In Dalton Transactions 53(5). p.2242-2251- Abstract
The magnetic and electronic structures of Fe4O5 have been investigated at ambient and high pressures via a combination of representation analysis, density functional theory (DFT+U) calculations, and Mössbauer spectroscopy. A few spin configurations corresponding to the different irreducible representations have been considered. The total-energy calculations reveal that the magnetic ground state of Fe4O5 corresponds to an orthogonal spin order. Depending on the magnetic propagation vector k, two spin-ordered phases with minimal energy differences are realized. The lowest energy magnetic phase is related to k = (0, 0, 0) and is characterized by ferromagnetic ordering of iron magnetic moments at... (More)
The magnetic and electronic structures of Fe4O5 have been investigated at ambient and high pressures via a combination of representation analysis, density functional theory (DFT+U) calculations, and Mössbauer spectroscopy. A few spin configurations corresponding to the different irreducible representations have been considered. The total-energy calculations reveal that the magnetic ground state of Fe4O5 corresponds to an orthogonal spin order. Depending on the magnetic propagation vector k, two spin-ordered phases with minimal energy differences are realized. The lowest energy magnetic phase is related to k = (0, 0, 0) and is characterized by ferromagnetic ordering of iron magnetic moments at prismatic sites along the b-axis and antiferromagnetic ordering of iron moments at octahedral sites along the c-axis. For the k = (1/2, 0, 0) phase, the moments in the prisms are antiferromagnetically ordered along the b-axis and the moments in the octahedra are still antiferromagnetically ordered along the c-axis. Under high pressure, Fe4O5 exhibits magnetic transitions with the corresponding electronic transitions of the metal-insulator type. At a critical pressure PC ∼ 60 GPa, the Fe ions at the octahedral sites undergo a high-spin to low-spin state crossover with a decrease in the unit-cell volume of ∼4%, while the Fe ions at the prismatic sites remain in the high-spin state up to 130 GPa. This site-dependent magnetic collapse is experimentally observed in the transformation of Mössbauer spectra measured at room temperature and high pressures.
(Less)
- author
- Zhandun, Vyacheslav S. ; Kazak, Natalia V. ; Kupenko, Ilya ; Vasiukov, Denis M. LU ; Li, Xiang ; Blackburn, Elizabeth LU and Ovchinnikov, Sergei G.
- organization
- publishing date
- 2023-12-19
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Dalton Transactions
- volume
- 53
- issue
- 5
- pages
- 10 pages
- publisher
- Royal Society of Chemistry
- external identifiers
-
- pmid:38193857
- scopus:85182388123
- ISSN
- 1477-9226
- DOI
- 10.1039/d3dt03437b
- language
- English
- LU publication?
- yes
- id
- 6f10a081-4ffd-4ab7-a8f1-e8e278fe62b1
- date added to LUP
- 2024-02-15 10:32:22
- date last changed
- 2024-09-18 00:30:31
@article{6f10a081-4ffd-4ab7-a8f1-e8e278fe62b1, abstract = {{<p>The magnetic and electronic structures of Fe<sub>4</sub>O<sub>5</sub> have been investigated at ambient and high pressures via a combination of representation analysis, density functional theory (DFT+U) calculations, and Mössbauer spectroscopy. A few spin configurations corresponding to the different irreducible representations have been considered. The total-energy calculations reveal that the magnetic ground state of Fe<sub>4</sub>O<sub>5</sub> corresponds to an orthogonal spin order. Depending on the magnetic propagation vector k, two spin-ordered phases with minimal energy differences are realized. The lowest energy magnetic phase is related to k = (0, 0, 0) and is characterized by ferromagnetic ordering of iron magnetic moments at prismatic sites along the b-axis and antiferromagnetic ordering of iron moments at octahedral sites along the c-axis. For the k = (1/2, 0, 0) phase, the moments in the prisms are antiferromagnetically ordered along the b-axis and the moments in the octahedra are still antiferromagnetically ordered along the c-axis. Under high pressure, Fe<sub>4</sub>O<sub>5</sub> exhibits magnetic transitions with the corresponding electronic transitions of the metal-insulator type. At a critical pressure P<sub>C</sub> ∼ 60 GPa, the Fe ions at the octahedral sites undergo a high-spin to low-spin state crossover with a decrease in the unit-cell volume of ∼4%, while the Fe ions at the prismatic sites remain in the high-spin state up to 130 GPa. This site-dependent magnetic collapse is experimentally observed in the transformation of Mössbauer spectra measured at room temperature and high pressures.</p>}}, author = {{Zhandun, Vyacheslav S. and Kazak, Natalia V. and Kupenko, Ilya and Vasiukov, Denis M. and Li, Xiang and Blackburn, Elizabeth and Ovchinnikov, Sergei G.}}, issn = {{1477-9226}}, language = {{eng}}, month = {{12}}, number = {{5}}, pages = {{2242--2251}}, publisher = {{Royal Society of Chemistry}}, series = {{Dalton Transactions}}, title = {{Orthogonal magnetic structures of Fe<sub>4</sub>O<sub>5</sub> : representation analysis and DFT calculations}}, url = {{http://dx.doi.org/10.1039/d3dt03437b}}, doi = {{10.1039/d3dt03437b}}, volume = {{53}}, year = {{2023}}, }