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arXiv · 0910.5302

Density functional characterization of the antiferromagnetism in oxygen-deficient anatase and rutile TiO2

Kesong Yang·Ying Dai·Baibiao Huang·Yuanping Feng
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Abstract

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 $μ_B$ 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.

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Kesong Yang, Ying Dai, Baibiao Huang, Yuanping Feng. 2009-10-28. Density functional characterization of the antiferromagnetism in oxygen-deficient anatase and rutile TiO2. https://doi.org/10.1103/physrevb.81.033202

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