Abstract This article is about structural, electronic, optical and thermoelectric properties of metal halide double perovskites Cs2AgInX6 (X = F, Cl, Br, I). These properties are computed using the highly accurate full potential linearized augmented plane wave method based of density functional theory. To acquire suitable ground state lattice parameters, generalized gradient approximation has been used. The calculated structural parameters are found in excellent agreement with the available literature. In addition, modified Becke-Johnson potential is taken into account for precise calculation of band structures. These structures discover the direct semiconducting nature of investigated compounds, however, value of the band gap decreases from F to I anion replacement. As consequences, the optical absorption edge shifts toward lower energies. To further evaluate physical behavior, thermoelectric properties such as Seebeck coefficients, thermal conductivities, electrical conductivities and figure of merits are also calculated. This study specifies present double perovskites as probable candidates for optical and thermoelectric devices.

中文翻译：

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阴离子置换对金属卤化物双钙钛矿Cs2AgInX6 (X=F, Cl, Br, I)物理性质的影响

摘要 本文介绍了金属卤化物双钙钛矿 Cs2AgInX6 (X = F, Cl, Br, I) 的结构、电子、光学和热电性能。这些特性是使用基于密度泛函理论的高精度全电位线性化增强平面波方法计算的。为了获得合适的基态晶格参数，使用了广义梯度近似。计算出的结构参数与现有文献非常吻合。此外，在能带结构的精确计算中考虑了修正的 Becke-Johnson 势。这些结构发现了所研究化合物的直接半导体性质，但是，带隙值从 F 到 I 阴离子置换降低。结果，光吸收边缘向较低能量移动。为了进一步评估物理行为，还计算了热电特性，例如塞贝克系数、热导率、电导率和品质因数。该研究将目前的双钙钛矿指定为光学和热电器件的可能候选物。