Search of new lead free perovskite for solar cell and other optoelectronic applications is an active area of research. Herein, we report investigation of the detailed structural, electronic and optical properties of the tin based perovskite, X₂SnY₆ (X = K, Rb, Cs; Y= Cl, Br, I), using density functional theory (DFT). A highly accurate scheme of the DFT, full potential linearized augmented plane wave method, was employed for present calculations. Structural parameters obtained through volume optimization process were found in fair agreement with available experimental results. The electronic band structure indicates direct band nature making them ideal for various optoelectronic applications. The prominent contribution to the density of states comes from Sn-s and X-p orbitals. The optical properties suggest that Cs₂SnI₆ and Rb₂SnI₆ possess maximum optical absorption. Moreover, some of the compounds with I anions have band gap in the order of 1 eV, indicating their ability for efficient optoelectronic devices.

寻找用于太阳能电池和其他光电应用的新型无铅钙钛矿是一个活跃的研究领域。在此，我们报告了对锡基钙钛矿X ₂ SnY ₆的详细结构，电子和光学性质的研究。（X = K，Rb，Cs; Y = Cl，Br，I），使用密度泛函理论（DFT）。DFT的高精度方案，全电位线性化增强平面波方法，用于当前计算。通过体积优化过程获得的结构参数与可获得的实验结果完全吻合。电子频带结构表明直接频带性质，使其成为各种光电应用的理想选择。Sn-s和Xp轨道对态密度的显着贡献。光学性质表明Cs ₂ SnI ₆和Rb ₂ SnI ₆具有最大的光吸收。此外，某些带有I阴离子的化合物的带隙约为1 eV，表明它们具有有效的光电器件的能力。