层状类钙钛矿有机-无机杂合物(C_nH_(2n+1)NH_3)_2SnI_4的第一性原理研究  

First Principle Calculations of the Layered Perovskite-type Organic-inorganic Hybrids (C_nH_(2n+1)NH_3)_2SnI_4

作　　者：郭丽玲[1] 翟晓雪[1] 孙璋[1] 刘韩星[1] 

机构地区：[1]武汉理工大学材料科学与工程学院,武汉430070

出　　处：《武汉理工大学学报》2013年第9期16-20,共5页Journal of Wuhan University of Technology

基　　金：国家自然科学基金(NSFC50972113,NSFC51372187)

摘　　要：用第一性原理方法,计算了空间群分别为Pbca和P21/a的杂合物(C4H9NH3)2SnI4、(C12H25NH3)2SnI4。计算结果表明,费米面附近的能带来自无机元中各原子的原子轨道,无机元的结构直接决定了带隙的大小,其中桥位碘连接的Sn—I—Sn键角对带隙大小有明显影响,该键角偏离180°幅度越大,带隙就越大。有机元的原子轨道对费米面附近的能带无贡献,不直接对带隙产生影响。但有机元对无机元有模板作用,不同有机元的氨基头与无机层之间的夹角不同,与无机层中的碘原子形成不同氢键。氢键的大小与方向会引起Sn—I—Sn键角的变化,从而间接地改变带隙。Ab inito functional theory study on layered organic-inorganic perovskite-type hybrids （（;4 H9 NH3 ）2 SnI4 and （C12H25 NH3 ）2 SnI4 （their space group are Pbca and P21/a）. The results indicate that band gap nearby Fermi surface comes from inorganic layers. Thus, the band gap is determined by the structure of the inorganic part. The Sn-I-Sn bond angle of the bridge I is the most important influencing factor on the band gap. The more deviation from 180° the bond angle is, the larger the band gap is. The organic layer does not influence the band gap directly, but the organic parts template the inorganic layer through interlayer hydrogen bonds. The angle between the amino head and the inorganic layer is different with the different organic components. The strength and the orientation of the hydrogen bond would result in the change of the Sn-I-Sn angle thus change the hand gap indirectly.

关 键 词：层状类钙钛矿 有机一无机杂合物 第一性原理计算 带隙 

分 类 号：Q438.2[生物学—生理学]