Electronic structure and magnetic properties of BaTi1-xMnxO3

• Published in: Current applied physics 2018, 18(2), , pp.150-154
• Main Authors: Dang, N.V., Dang, N.T., Ho, T.A., Tran, N., Phan, T.L.
• Format: Article
• Language: English
• Subjects: A. Mn-BaTiO3 multiferroics; C. Electronic structure; C. Magnetic properties; 물리학
• ISSN: 1567-1739; 1878-1675
• DOI: 10.1016/j.cap.2017.11.020

The electronic structure and magnetic properties of polycrystalline BaTi1-xMnxO3 (x = 0–0.1) compounds prepared by solid-state reactions were studied. The results revealed that the increase in Mn content (x) did not change the oxidation numbers of Ba (+2) and Ti (+4) in BaTi1-xMnxO3. However, there is the change in Mn valence that Mn3+,4+ ions coexist in the samples with x = 0.01–0.04 while Mn4+ ions are almost dominant in the samples with x = 0.06–0.1. We also point out that Mn3+ and Mn4+ ions substitute for Ti4+ and prefer locating in the tetragonal and hexagonal BaTiO3 structures, respectively, in which the hexagonal phase constitutes soon as x = 0.01. Particularly, all the samples exhibit room-temperature ferromagnetism. Ferromagnetic order increases with increasing x from 0 to 0.02, but decreases as x ≥ 0.04. We think that ferromagnetism in BaTi1-xMnxO3 is related to lattice defects and/or exchange interactions between Mn3+ and Mn4+ ions. •Tetragonal-to-hexagonal phase transformation in BaTi1-xMnxO3 as x > 0.01.•Oxidation-state shift of Mn3+ → Mn4+ as x > 0.04.•Magnetic phase separation caused by the valence shift of Mn.•Ferromagnetic order caused by exchange interactions between Mn3+ and Mn4+.