The vacancy ordered double perovskites are attractive materials for applications in optoelectronics, and other renewable energy technologies. In this research work, we have addressed the electronic, optical, thermoelectric, and thermodynamic properties of Cs₂TiCl₆ and Cs₂TiBr₆ double perovskites. The structural and dynamical stability is ensured by Goldsmith tolerance factor and positive phonon frequencies, respectively. The elastic constants, Poisson's, and Pugh's ratio show the mechanical stability and ductile behavior. Their ultralow thermal conductivity appears as important factors for device fabrication. The band structures reveal indirect band gaps 2.87eV, and 2.17eV for Cs₂TiCl₆ and Cs₂TiBr₆, respectively. The optical analysis has been done using the computed dielectric constant, absorption coefficient and refractive index. Thermoelectric calculations are executed using BoltzTraP code to investigate the electrical conductivity, thermal conductivity and Seebeck coefficient. The computed figure of merit (0.75 for Cs₂TiCl₆ and 0.78 for Cs₂TiBr₆) at room temperature reveals their excellent potential renewable energy applications.

空位有序双钙钛矿是用于光电子和其他可再生能源技术的有吸引力的材料。在这项研究工作中，我们研究了 Cs ₂ TiCl ₆和 Cs ₂ TiBr ₆双钙钛矿的电子、光学、热电和热力学特性。Goldsmith 容差因子和正声子频率分别确保了结构和动力学稳定性。弹性常数、泊松比和普格比显示了机械稳定性和延展性。它们的超低热导率似乎是器件制造的重要因素。能带结构揭示了 Cs ₂ TiCl _{6 的}间接带隙 2.87eV 和 2.17eV和Cs ₂ TiBr ₆，分别。使用计算出的介电常数、吸收系数和折射率进行了光学分析。使用 BoltzTraP 代码执行热电计算，以研究电导率、热导率和塞贝克系数。所计算的品质因数（0.75 Cs的图₂的TiCl ₆和铯0.78 ₂ TiBr ₆）在室温下揭示了其优异的潜在可再生能源应用。