Thi Han Nguyen, Khuong Dien Vo, Lin Ming-Fa
Department of Physics, National Cheng Kung University, 701 Tainan, Taiwan.
Hierarchical Green-Energy Material (Hi-GEM) Research Center, National Cheng Kung University, 701 Tainan, Taiwan.
ACS Omega. 2022 Jul 13;7(29):25210-25218. doi: 10.1021/acsomega.2c02088. eCollection 2022 Jul 26.
We used first-principles calculations to investigate the electrical and optical properties of CsGeX (X = Cl, Br, and I) compounds. These materials present rich and unique physical and chemical phenomena, such as the optimal geometric structure, the electronic band structure, the charge density distribution, and the special van Hove singularities in the electronic density of states. The optical properties cover a slight red shift of the optical gap, corresponding to weak electron-hole interactions, strong absorption coefficients, and weak reflectance spectra. The presented theoretical framework will provide a full understanding of the various phenomena and promising applications for solar cells and other electro-optic materials.
我们采用第一性原理计算来研究CsGeX（X = Cl、Br和I）化合物的电学和光学性质。这些材料呈现出丰富而独特的物理和化学现象，如最优几何结构、电子能带结构、电荷密度分布以及电子态密度中特殊的范霍夫奇点。光学性质包括光学带隙的轻微红移，这对应着较弱的电子 - 空穴相互作用、较强的吸收系数和较弱的反射光谱。所提出的理论框架将有助于全面理解各种现象，并为太阳能电池和其他电光材料带来有前景的应用。
