The effect of electron localization on the electronic structure and migration barrier of oxygen vacancies in rutile

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	The effect of electron localization on the electronic structure and migration barrier of oxygen vacancies in rutile
	L. G. Zhu; Q. M. Hu; R. Yang
	2014
发表期刊	Journal of Physics-Condensed Matter
ISSN	0953-8984
卷号	26 期号:5
摘要	By applying the on-site Coulomb interaction (Hubbard term U) to the Ti d orbital, the influence of electron localization on the electronic structure as well as the transport of oxygen vacancies (V-O) in rutile was investigated. With U = 4.5 eV, the positions of defect states in the bandgap were correctly reproduced. The unbonded electrons generated by taking out one neutral oxygen atom are spin parallel and mainly localized on the Ti atoms near V-O, giving rise to a magnetic moment of 2 mu(B), in agreement with the experimental finding. With regard to the migration barrier of V-O, surprisingly, we found that U = 4.5 eV only changed the value of the energy barrier by +/- 0.15 eV, depending on the diffusion path. The most probable diffusion path (along [1 (1) over bar0]) is the same as that calculated by using the traditional GGA functional. To validate the GGA + U method itself, a hybrid functional with a smaller supercell was used, and the trend of the more probable diffusion path was not changed. In this regard, the traditional GGA functional might still be reliable in the study of intrinsic-defect transportation in rutile. Analyzing the atomic distortion and density of states of the transition states for different diffusion paths, we found that the anisotropy of the diffusion could be rationalized according to the various atomic relaxations and the different positions of the valence bands relative to the Fermi level of the transition states.
部门归属	[zhu, linggang ; hu, qing-miao ; yang, rui] chinese acad sci, shenyang natl lab mat sci, inst met res, shenyang 110016, peoples r china. ; zhu, lg (reprint author), chinese acad sci, shenyang natl lab mat sci, inst met res, shenyang 110016, peoples r china. ; qmhu@imr.ac.cn
关键词	Dft Plus u Bandgap State Diffusion Total-energy Calculations Wave Basis-set Tio2 Dynamics Anatase Metals Oxide Bulk
URL	查看原文
语种	英语
文献类型	期刊论文
条目标识符	http://ir.imr.ac.cn/handle/321006/72511
专题	中国科学院金属研究所
推荐引用方式 GB/T 7714	L. G. Zhu,Q. M. Hu,R. Yang. The effect of electron localization on the electronic structure and migration barrier of oxygen vacancies in rutile[J]. Journal of Physics-Condensed Matter,2014,26(5).
APA	L. G. Zhu,Q. M. Hu,&R. Yang.(2014).The effect of electron localization on the electronic structure and migration barrier of oxygen vacancies in rutile.Journal of Physics-Condensed Matter,26(5).
MLA	L. G. Zhu,et al."The effect of electron localization on the electronic structure and migration barrier of oxygen vacancies in rutile".Journal of Physics-Condensed Matter 26.5(2014).