Following recent computational discovery of the Cs₂InSbCl₆ and Cs₂InBiCl₆ compounds, density functional theory screening of their fundamental physical properties is warranted to establish their potential as optoelectronic materials. Thus, in this paper, we report the results of detailed calculations of the structural, elastic, electronic, and optical properties of the Cs₂InSbCl₆ and Cs₂InBiCl₆ crystals using the full-potential augmented plane wave plus local orbitals method with the generalized gradient approximation (GGA) and Tran–Blaha modified Becke–Johnson potential (TB-mBJ) to model the exchange–correlation interactions. Calculations were performed both with and without including spin–orbit coupling effect. Ab initio molecular dynamics calculations show the thermal stability of the title compounds at 300 K. Predicted elastic constants show that the studied materials exhibit moderate resistant to external stress, strong elastic anisotropy, ductile nature, and mechanical stability. Cs₂InSbCl₆ and Cs₂InBiCl₆ are direct bandgap (Г–Г) semiconductors. Calculated optical properties reveal that the title compounds are characterized by strong absorption in a large energy window including the high-energy part of the sun visible spectrum.

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中文翻译：

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Cs2InSbCl6和Cs2InBiCl6双钙钛矿的一些基本物理性质的密度泛函理论筛选

随着最近对 Cs ₂ InSbCl ₆和 Cs ₂ InBiCl ₆化合物的计算发现，有必要对其基本物理性质进行密度泛函理论筛选，以确定它们作为光电材料的潜力。因此，在本文中，我们报告了 Cs ₂ InSbCl ₆和 Cs ₂ InBiCl _{6的结构、弹性、电子和光学性质的详细计算结果。}晶体使用具有广义梯度近似 (GGA) 的全势增强平面波加局部轨道方法和 Tran-Blaha 改进的贝克-约翰逊势 (TB-mBJ) 来模拟交换相关相互作用。在有和没有包括自旋轨道耦合效应的情况下进行计算。从头算分子动力学计算显示标题化合物在 300 K 下的热稳定性。预测的弹性常数表明，所研究的材料表现出适度的外部应力耐受性、强弹性各向异性、延展性和机械稳定性。Cs ₂ InSbCl ₆和 Cs ₂ InBiCl ₆是直接带隙（Г-Г）半导体。计算的光学性质表明，标题化合物的特征在于在包括太阳可见光谱的高能部分在内的大能量窗口中具有强吸收。

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