硅酸盐学报

钙钛矿陶瓷La_1－xCa_xMnO₃ (x＝0.10, 0.15, 0.20)的光电子能谱

作者：张红光卞永淞马笑尘郑伟晗李永涛刘胜利包刚

单位：南京邮电大学理学院南京210023

分类号：TB34

出版年,卷(期):页码：2014,42(7):857-861

DOI：10.7521/j.issn.0454－5648.2014.07.08

摘要：

对溶胶凝胶法制备的钙掺杂LaMnO3多晶陶瓷材料La1－xCaxMnO3 (x＝0.10, 0.15，0.20)进行了X射线衍射和各个元素的光电子能谱研究，其X射线衍射实验表明：该系列样品表现出很好的单相性，其空间结构为正交型Pbnm。Mn2p，La4d，O1s能级的光电子能谱结果表明：当掺杂浓度较低时，Ca离子在La位的掺杂不会引起La和O元素电子组态的变化，只引起Mn离子的化学价态变化。利用组态相互作用团簇模型计算了Mn2p光电子能谱，得到晶体场分裂能10Dq＝1.0eV，电荷转移能Δ＝5eV，d轨道之间的库伦排斥能Udd＝4eV，pd轨道之间的库伦排斥能Upd＝4.4eV，过渡金属离子d轨道和近邻O离子之间的轨道杂化能T(eg)＝3.8eV。

The La1－xCaxMnO3 (x＝0.10, 0.15，0.20) was prepared by a sol－gel method. The samples were characterized by X－ray diffraction and X－ray photoelectron spectroscopy. According to the results by XRD, these samples are awell－single phase with the Pbnm orthorhombic crystal structure. From the XPS spectra of Mn 2p，La 4d，O 1s core levels, there is little chemical shift for La and O ions, but a slight change for Mn ions at a low doping concentration. The Mn 2p core level was also calculated by a configuration interaction cluster model. The parameters are crystal field splitting energy (10Dq) of 1.0 eV, charge transfer (Δ) of 5 eV, dd Coulombic repulsion potential (Udd) of 4 eV, pd Coulombic repulsion potential (Upd) of 4.4 eV, and energy of transitional metal d orbital hybridized with ligand oxygen orbital (T(eg)) of 3.8 eV, respectively.

基金项目：

南京邮电大学引进人才科研启动基金(NY213055)；江苏省高校自然科学基金(13KJB140011)；江苏省自然科学青年基金(BK20130858)。

作者简介：

第一作者：张红光(1985—)，男，博士，讲师。

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