Cesium halide double-perovskites (Cs₂AgCrX₆; X = Cl, Br, and I) have been investigated for potential applications in optoelectronic devices. Density functional theory (DFT) has been utilized to study the structural, chemical bonding, electronic, mechanical, optical, and thermoelectric properties of these materials. Structural analysis has revealed that these compounds favor a face-centered cubic double-perovskite crystal structure with space group Fm-3m. The electronic properties show that Cs₂AgCrX₆ (X = Cl, Br) are indirect whereas Cs₂AgCrI₆ is a direct band-gap semiconductor, and their band-gap values are 2.81, 2.1, and 0.9 eV, respectively. The bonding nature between Ag-X and Cr-X atoms is covalent, while ionic bonds exist between Cs-X atoms. The systems are good dielectric materials and have the potential to be used in optoelectronic devices. Post-DFT calculations have been performed to calculate thermoelectric parameters. The increase of the Seebeck coefficient in these materials with temperature up to 400 K satisfies the Mott formula. Above this temperature, thermal excitations of extrinsic carriers decrease the Seebeck coefficient. The mechanical properties of these compounds indicate that they are ductile and anisotropic.

已经研究了卤化铯双钙钛矿（Cs ₂ AgCrX ₆；X = Cl、Br 和 I）在光电器件中的潜在应用。密度泛函理论 (DFT) 已被用于研究这些材料的结构、化学键合、电子、机械、光学和热电特性。结构分析表明，这些化合物有利于具有空间群Fm -3 m的面心立方双钙钛矿晶体结构。电子特性表明 Cs ₂ AgCrX ₆ (X = Cl, Br) 是间接的，而 Cs ₂ AgCrI ₆是直接带隙半导体，它们的带隙值分别为 2.81、2.1 和 0.9 eV。Ag-X 和 Cr-X 原子之间的键合性质是共价键，而 Cs-X 原子之间存在离子键。该系统是良好的介电材料，具有用于光电器件的潜力。已执行后 DFT 计算以计算热电参数。这些材料的塞贝克系数随温度升高到 400 K 的增加满足莫特公式。高于此温度，外在载流子的热激发会降低塞贝克系数。这些化合物的机械性能表明它们具有延展性和各向异性。