Density-functional characterization of antiferromagnetism in oxygen-deficient anatase and rutile TiO 2
Density-functional characterization of antiferromagnetism in oxygen-deficient anatase and rutile TiO 2
复制标题
DOI：
10.1103/physrevb.81.033202
复制
发表时间：
2009-10
影响因子：
3.7
通讯作者：
Kesong Yang;Ying Dai;Baibiao Huang;Y. Feng
中科院分区：
文献类型：
--
作者：
Kesong Yang;Ying Dai;Baibiao Huang;Y. Feng
我们为近期实验[周S等人，《物理评论B》79，113201（2009）]中观察到的缺氧锐钛矿和金红石TiO₂中Ti³⁺离子的局域磁矩提供了理论依据。我们的第一性原理GGA + U计算结果表明，在锐钛矿相中，一个氧空位会将两个Ti⁴⁺离子转变为两个Ti³⁺离子，这导致每个Ti³⁺的局域磁矩为1.0 μB。然而，这两个Ti³⁺离子形成了稳定的反铁磁态，并且在缺氧金红石相TiO₂中也观察到了类似的反铁磁性。计算结果与缺氧Ti - O体系中实验观察到的类反铁磁行为非常吻合。
We present theoretical evidence for local magnetic moments on Ti3+ ions in oxygen-deficient anatase and rutile TiO2 observed in a recent experiment [S. Zhou, et al., Phys. Rev. B 79, 113201 (2009)]. Results of our first-principles GGA+U calculations reveal that an oxygen vacancy converts two Ti4+ ions to two Ti3+ ions in anatase phase, which results in a local magnetic moment of 1.0 $\mu_B$ per Ti3+. The two Ti3+ ions, however, form a stable antiferromagnetic state, and similar antiferromagnetism is also observed in oxygen-deficient rutile phase TiO2. The calculated results are in good agreement with the experimentally observed antiferromagnetic-like behavior in oxygen-deficient Ti-O systems.