Abstract During the last decade, Inorganic Halide Double Perovskite materials have attracted widespread interest as a promising eco-friendly and non-toxic alternative to lead based hybrid halide organic–inorganic perovskites materials, with outstanding Stability, Structural and electronic properties. In this study, First-Principles density functional theory (DFT) calculations were performed on the structural, stability, electronic and optical properties of the transition metal-based double perovskites materials Cs2InGaX6 (X = Cl, Br, or I). Our results reveal that all these materials exhibit excellent thermodynamic and structural stability owing to their negative formation energies and Goldsmith's factors. It is also observed that Cs2InGaCl6, Cs2InGaBr6, and Cs2InGaI6 materials exhibit band gaps calculated by different functional (GGA-PBE and TB-mpj) in visible-range between 0.89 and 3.24 eV. Furthermore, the computed optical properties reveal strong absorption in UV, visible, and IR range with high optical conductivity and low reflectivity. These obtained results predict that the three transition metal-based double perovskites materials carries promising application in nano-electronic and optoelectronic device applications and can be considered as photovoltaic absorber materials.

中文翻译：

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Cs2InGaX6（X=Cl、Br 或 I）：具有增强光电特性的新兴无机卤化物双钙钛矿

摘要 在过去十年中，无机卤化物双钙钛矿材料作为一种有前途的环保无毒铅基杂化卤化物有机-无机钙钛矿材料的替代品，具有出色的稳定性、结构和电子特性，引起了广泛的关注。在这项研究中，对基于过渡金属的双钙钛矿材料 Cs2InGaX6（X = Cl、Br 或 I）的结构、稳定性、电子和光学性质进行了第一性原理密度泛函理论 (DFT) 计算。我们的结果表明，由于它们的负形成能和戈德史密斯因素，所有这些材料都表现出优异的热力学和结构稳定性。还观察到 Cs2InGaCl6、Cs2InGaBr6、和 Cs2InGaI6 材料在 0.89 和 3.24 eV 之间的可见光范围内表现出由不同功能（GGA-PBE 和 TB-mpj）计算的带隙。此外，计算出的光学特性显示在紫外线、可见光和红外线范围内具有高光导率和低反射率的强吸收。这些获得的结果预测这三种基于过渡金属的双钙钛矿材料在纳米电子和光电器件应用中具有广阔的应用前景，可被视为光伏吸收材料。