The electronic structure and optical absorption spectrum of V^{0} and V^{-} center in MgO are investigated using first-principles calculations based on density functional theory. It is demonstrated that the configuration with distortion is energetically favorable in PBE0 functional. The six O atoms around Mg vacancy are non-equivalent due to the distortion. The defect states localized in the band gap are obtained by applying hybrid functional calculations, which is very important for optical properties. At ambient condition, the absorption peak at ~2.5 and ~2.6 eV is assigned to V^{0} and V^{-} center, respectively. With increasing pressure, the absorption peak shows blue shift. The trend is consistent with the experimental observation.
Decoupling interface and thickness effects on hydrogen absorption in V/MgO: experiments and DFT
School of Electronic Technology and Engineering, Shanghai Technical Institute of Electronics and Information（上海电子信息职业技术学院电子技术与工程学院）；School of Materials Science and Engineering, Shanghai University（上海大学材料科学与工程学院）
Magnetic and Electronic Structure study of Fe/MgO/Fe/Co Multilayer Stack Deposited by E-Beam Evaporation
本文研究了用电子束蒸发方法在Si（100）衬底上生长的MgO/Fe/MgO/Fe/Co/Au多层膜的磁性和电子结构。X射线衍射研究描绘了多晶性质的多层膜。从振动样品磁强计（VSM）和近边X射线吸收精细结构谱（NEXAFS）在Fe & Co L-和Mg & O K-边缘获得的结果被应用于了解该堆栈的磁性和电子特性及其界面特性。表面灵敏总电子产额（TEY）模式记录的Fe L边光谱的光谱特征表明在Fe/MgO界面形成了FeOx，体敏总荧光产额（TFY）模式记录的Fe L边光谱的光谱特征表明Fe为金属性质。Co L边光谱揭示了在TEY和TFY模式中钴的金属性质的存在。上述结果与X射线反射法有很好的相关性。
Optical absorption spectra of metal oxides from time-dependent density functional theory and many-body perturbation theory based on optimally-tuned hybrid functionals
