Sincrotrone Trieste, Area Science Park, Basovizza (Ts), Italy.
J Phys Condens Matter. 2012 Feb 1;24(4):045504. doi: 10.1088/0953-8984/24/4/045504. Epub 2012 Jan 5.
Resonant valence band x-ray photoelectron spectra (ResPES) excited near the 2p(3/2) core level energies, 2p x-ray photoelectron spectra (XPS) and L(3,2) x-ray absorption spectra (XAS) of Ti and Mn in single crystals of 1T-Mn(0.2)TiSe(2) were studied for the first time. The ionic-covalent character of the bonds formed by the Mn atoms with the neighboring Se atoms in the octahedral coordination is established. From the XPS and XAS measurements compared with the results of atomic multiplet calculations of Ti and Mn L(3,2) XAS, it is found that the Ti atoms are in the ionic state of 4 + and the Mn atoms are in the state of 2 +. In ResPES of Mn(0.2)TiSe(2) excited near the Ti 2p(3/2) and Mn 2p(3/2) absorption edges the Ti 3d and Mn 3d bands at binding energies just below the Fermi level are observed. According to theoretical calculations of E(k) the Ti 3d states are localized in the vicinity of the Γ point and the Mn 3d states are localized along the direction K-Γ-M in the Brillouin zone of the crystal.
首次研究了 1T-Mn(0.2)TiSe(2)单晶中 Ti 和 Mn 的共振价带 X 光电子能谱(ResPES)激发近 2p(3/2)芯能级、2p X 光电子能谱(XPS)和 L(3,2)X 射线吸收光谱(XAS)。确立了 Mn 原子与八面体配位中相邻 Se 原子形成的键的离子-共价性质。通过 XPS 和 XAS 测量与 Ti 和 Mn L(3,2)XAS 的原子多组态计算结果进行比较,发现 Ti 原子处于 4+的离子态,Mn 原子处于 2+的状态。在 Mn(0.2)TiSe(2)的 ResPES 激发近 Ti 2p(3/2)和 Mn 2p(3/2)吸收边时,在费米能级以下的结合能处观察到 Ti 3d 和 Mn 3d 带。根据 E(k)的理论计算,Ti 3d 态在Γ点附近局域化,Mn 3d 态在晶体布里渊区的 K-Γ-M 方向上局域化。