钼掺杂镧钙锶锰氧化物的化学价态和电子结构

Valence States and Electronic Structure of Mo Doped La_(0.7)Sr_(0.15)Ca_(0.15)MnO_3

采用传统固相法分别利用不同价态的MoO3和MoO2原料制备了Mo掺杂Mn位的La0.7Sr0.15Ca0.15-MnO3材料,主要利用光电子能谱和X射线吸收谱研究了过渡金属元素的电子结构特征和化学价态的不同。结果表明:用两种价态的Mo原料制备的钙钛矿锰氧化物体系的Mo离子价态表现不同,MoO2制备的材料体系价态偏低。同时,该变化还引起了Mn离子电子结构变化以及氧原子轨道能级与周围配位原子能级杂化强度的不同,这些内在电子结构的不同将成为材料表现出不同物理属性的可能原因。

The Mo doped La0.7 Sr0.15 Ca0.15 MnO3 were prepared by different raw material MoO3 and MoO2 with distinct valence states of Mo ion respectively using a conventional solid-state route. The electronic structure and va lence states of those two samples were mainly investigated by photoelectron spectroscopy and X-ray absorption spectroscopy. The results show that the valence state of Mo ion in prepared sample by MoO2 is a little lower than that prepared by MoO3, and the related electronic structure of Mn ion and the hybridization between O 2p orbital state and ligand atomic energy level are correspondingly affected, which may be the reason of the distinct physical properties exhibited in Mo doped samples.