First principles calculation of magnetic order in a low-temperature phase of the iron ludwigite
| Autor: | Maria Matos, André S. Pimentel, J. Terra, Donald E. Ellis |
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| Rok vydání: | 2015 |
| Předmět: |
Materials science
Magnetic order Spins Spin polarization Condensed matter physics Fe ludwigite Crystal structure Condensed Matter Physics DFT Electronic Optical and Magnetic Materials Spin magnetic moment Magnetization Phase (matter) Atom Non-collinear spin Theory Condensed Matter::Strongly Correlated Electrons Spin (physics) |
| Zdroj: | Journal of Magnetism and Magnetic Materials. 374:148-152 |
| ISSN: | 0304-8853 |
| Popis: | The magnetic order of a low-temperature dimerized phase of Fe 3 O 2 BO 3 is investigated through a density functional approach which considers full non-collinear spin–spin interactions, focusing on the 15 K crystalline structure. It is found that Fe spins in the (Fe–Fe) 5+ dimer, formed during the room temperature structural change of Fe 3 O 2 BO 3 , are parallel and have little freedom to rotate under interaction with neighbor Fe atoms. While the Fe dimer behaves as a heavy single magnetic unit the spin magnetic moment of the third Fe 3+ atom of the Fe triad has, on the contrary, much more freedom to rotate. This is responsible for a canted spin ordering, revealed by a rotation of ~80° of the trivalent Fe spin relative to the spin orientation of the dimer, due to spin–spin interaction with divalent Fe atoms outside the triad . Canting is thus seen to be responsible for the very low net magnetization, experimentally observed in this compound ( T |
| Databáze: | OpenAIRE |
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