YFeO_3的电子结构和光学性质的第一性原理研究  

First-principles study on the electronic structure and optical properties of YFeO_3

作　　者：宋庆功[1,2] 刘立伟[2] 赵辉[2] 严慧羽[1] 杜全国[1] 

机构地区：[1]中国民航大学理学院低维材料与技术研究所,天津300300 [2]河北工业大学理学院,天津300130

出　　处：《物理学报》2012年第10期370-375,共6页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:60979008);中央高校基本科研业务费专项资金(批准号:ZXH2010D014)资助的课题~~

摘　　要：稀土正铁氧体YFeO_3呈正交钙钛矿结构,其晶体和纳米晶材料在电极材料、传感器和光催化领域具有重要的应用价值.用平面波赝势方法,采用广义梯度近似、改进的Perdew-Burke-Emzerhof交换-关联势、实空间超软赝势计算方案,研究了YFeO_3晶体的几何结构、电子结构和光学性质.计算得到的晶格参量与报道的实验结果一致.通过对能带结构、态密度、介电函数、吸收系数和光电导率的计算和分析,确定YFeO_3是直接能隙半导体,能隙E_g约为2.22 eV,阐明了YFeO_3晶体和纳米晶具有较好的可见光催化性能.Rare-earth orthoferrites （such as YFeO3） with orthorhombic perovskite-type structure are promising candidates in the fields of electrode materials, gas sensors and pbotocatalysts. The geometric structure, the electronic structure and the optical properties of YFeO3 crystal are investigated by using the plane-wave pseudo-potential method, with the scheme of generalized gradient approximation, revised Perdew-Burke-Emzerhof exchange-correlation potential and ultrasoft pseudopotential. The obtained lattice parameters are in good accordance with experimental results reported. The results confirm that YFeO3 crystal is a direct semiconductor with a gap （Eg） of about 2.22 eV, based on the analyses about band structure, density of state, dielectric function, absorption coefficient, and photoconductivity. It is clarified that YFeO3 crystal and nanocrystalline possess good photocatalytic activities for visible light.

关 键 词：YFeO3 第一性原理 电子结构 光学性质 

分 类 号：O482.3[理学—固体物理]