First-principles study on electronic structure and optical properties of Ca4Bi6O13 crystal
First-principles study on electronic structure and optical properties of Ca4Bi6O13 crystal
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DOI：
10.1016/j.jpcs.2012.07.012
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发表时间：
2013
影响因子：
4
通讯作者：
Hiroyuki Nakamura;Y. Obukuro;K. Obata;S. Matsushima;M. Arai;Kenkichiro Kobayashi
中科院分区：
文献类型：
--
作者：
Hiroyuki Nakamura;Y. Obukuro;K. Obata;S. Matsushima;M. Arai;Kenkichiro Kobayashi
用GGA方法计算了ca4bi6o13的电子结构。ca4bi6o13的价带最大值和导带最小值位于Γ-point。这意味着ca4bi6o13是一种直接带隙材料。低能级的导带主要由bi6p和o2p的混合物构成。高能区的传导带由Ca - 3d态组成。低能区价带主要由bi6s态组成，高能区价带由o2p态与bi6s、6p态杂化组成。根据复介电函数ε(ω)=ε1(ω)+ ε2（ω）的谱依赖性计算了ca4bi6o13的光学性质。在ε2（ω）函数中，在3.6eV以下有一个高极化峰。
The electronic structure of Ca4Bi6O13is calculated by the GGA approach. The valence band maximum and the conduction band minimum of Ca4Bi6O13are located at Γ-point. This means that Ca4Bi6O13is a direct band gap material. The conduction band in the lower energy region is mainly constructed with the admixture of Bi 6p and O 2p. The conduction band in the higher energy region consists of Ca 3d states. The valence band in the lower energy region is mainly formed from Bi 6s states, and the valence band in the upper energy region consists of O 2p states hybridizing with Bi 6s and 6p states. The optical properties of Ca4Bi6O13are calculated from spectral dependence of the complex dielectric function, ε(ω)=ε1(ω)+iε2(ω). A highly polarized peak is observed below 3.6eV in ε2(ω) function.