First-principles calculation of defect energetics in cubic-BaTiO3 and a comparison with SrTiO3
First-principles calculation of defect energetics in cubic-BaTiO3 and a comparison with SrTiO3
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DOI：
10.1016/j.actamat.2007.07.054
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发表时间：
2007-11
期刊：
影响因子：
9.4
通讯作者：
Hak-Sung Lee;T. Mizoguchi;Takahisa Yamamoto;Suk-joong L. Kang;Y. Ikuhara
中科院分区：
文献类型：
--
作者：
Hak-Sung Lee;T. Mizoguchi;Takahisa Yamamoto;Suk-joong L. Kang;Y. Ikuhara
采用第一性原理平面波赝势方法研究了BaTiO 3的结构弛豫和本征空位的形成能.将计算的缺陷形成能和原子弛豫与先前报道的SrTiO 3的数据[Tanaka T，Matsunaga K，Ikuhara Y，Yamamoto T. Phys Rev B 2003;68：205213]。结果表明，在氧化状态下，部分肖特基物种VTi ~（2-）+VO ~（2+）和VBa ~（2-）+VO ~（2+）的形成能最低。相反，随着氧化学势降低，即还原条件，O空位在BaTiO 3中占主导地位。关于原子弛豫，发现BaTiO 3和SrTiO 3显示出幅度上的差异。BaTiO_3的空位形成能高于SrTiO_3。
The structural relaxation and formation energies of intrinsic vacancies in cubic-BaTiO3were studied by using a first-principles plane-wave-based pseudopotential calculation. The calculated defect formation energies and the atomic relaxations were compared with previously reported data for SrTiO3[Tanaka T, Matsunaga K, Ikuhara Y, Yamamoto T. Phys Rev B 2003;68:205213]. It was found that the formation energies of the partial Schottky species, VTi2-+VO2+and VBa2-+VO2+, are the lowest in the oxidized condition. In contrast, as the oxygen chemical potential decreased, namely the reduced condition, the O vacancy becomes dominant in cubic-BaTiO3. Concerning the atomic relaxation, it was found that BaTiO3and SrTiO3show a difference in magnitude. It was also found that the overall vacancy formation energy in BaTiO3is higher than that in SrTiO3.