Magnetic phase transitions in the system La₁₋xBixMnO₃₊λ

• Published in: Физика низких температур
• Date: 2002
• Main Authors: Troyanchuk, I.O., Mantytskaja, O.S., Szymczak, H., Shvedun, M.Yu.
• Format: Article
• Language: English
• Published: Фізико-технічний інститут низьких температур ім. Б.І. Вєркіна НАН України 2002
• Subjects: Дефекты в кристаллах
• Online Access: https://nasplib.isofts.kiev.ua/handle/123456789/130236
• Journal Title: Digital Library of Periodicals of National Academy of Sciences of Ukraine
• Cite this: Magnetic phase transitions in the system La₁₋xBixMnO₃₊λ / I.O. Troyanchuk, O.S. Mantytskaja, H.Szymczak, M.Yu. Shvedun // Физика низких температур. — 2002. — Т. 28, № 7. — С. 790-795. — Бібліогр.: 28 назв. — англ.

The crystal structure and magnetic properties of the La₁₋xBixMnO₃₊λ system (0⩽x⩽1;λ⩽0.08) are studied as functions of the oxygen and bismuth contents. In oxidized samples La₁₋xBixMnO₃₊λ a phase transition from a ferromagnetic state (rhombohedric phase) to a state of the spin glass type (quasitetragonal phase) is observed with increase of the bismuth concentration. The reduced samples La₁₋xBixMnO₃ are weak ferromagnets down to x⩽0.6 and then transform into a ferromagnetic state. It is supposed that the Bi³⁺ ions stabilize the dx2−y2 orbitals in the nearest Mn³⁺ ions whereas the dz2 orbitals of the La³⁺ ions are stabilized. The orbitally disordered phases and dx2−y2-orbitally ordered phases are ferromagnetic, the dz2-orbitally ordered phases show antiferromagnetic ordering, and the state of the orbital glass type corresponds to a state of the spin glass type. The crystal structure and magnetic properties of the La₁₋xBixMnO₃₊λ system (0⩽x⩽1;λ⩽0.08) are studied as functions of the oxygen and bismuth contents. In oxidized samples La₁₋xBixMnO₃₊λ a phase transition from a ferromagnetic state (rhombohedric phase) to a state of the spin glass type (quasitetragonal phase) is observed with increase of the bismuth concentration. The reduced samples La₁₋xBixMnO₃ are weak ferromagnets down to x⩽0.6 and then transform into a ferromagnetic state. It is supposed that the Bi³⁺ ions stabilize the dx2−y2 orbitals in the nearest Mn³⁺ ions whereas the dz2 orbitals of the La³⁺ ions are stabilized. The orbitally disordered phases and dx2−y2-orbitally ordered phases are ferromagnetic, the dz2-orbitally ordered phases show antiferromagnetic ordering, and the state of the orbital glass type corresponds to a state of the spin glass type.