Fatmi M, Bouferrache K, Ghebouli M A, Ghebouli B, Alomairy S, Alanazi Faisal Katib
Research Unit on Emerging Materials (RUEM), University Ferhat Abbas of Setif 1, Setif, 19000, Algeria.
Department of Physics, Faculty of Science, University of M'sila University Pole, Road Bourdj Bou Arreiridj, 28000, M'sila, Algeria.
Sci Rep. 2025 Jul 30;15(1):27859. doi: 10.1038/s41598-025-13916-1.
In this research, the structural, electronic, optical, and thermoelectric properties of LiInX₂ (X = S, Te) compounds were investigated using first-principles calculations based on Density Functional Theory (DFT). The Full-Potential Linearized Augmented Plane Wave (FP-LAPW) method implemented in the Wien2k package was employed, with the Generalized Gradient Approximation (GGA) and Tran-Blaha modified Becke-Johnson (mBJ-GGA) approximation applied to study the electronic properties. The results revealed that LiInS₂ crystallizes in an orthorhombic system with space group Pna21, while LiInTe₂ crystallizes in a tetragonal system with space group I-42d. The lattice constants and elastic parameters were calculated, showing good agreement with available experimental values. The elastic properties, including elastic constants, moduli, and mechanical stability criteria, were also evaluated to provide insight into the structural robustness and potential mechanical performance of the compounds. Electronic band structure calculations revealed that both compounds possess direct band gaps, with values of 3.61 eV for LiInS₂ and 2.33 eV for LiInTe₂ using the mBJ-GGA approximation, which are close to experimental measurements. Phonon dispersion studies were conducted to verify the dynamic stability of both compounds. Our findings demonstrate that LiInX₂ (X = S, Te) compounds possess suitable electronic band structures, strong optical absorption in the visible and UV ranges, and favorable thermoelectric characteristics. These results highlight their potential as promising materials for both optoelectronic devices and thermoelectric energy conversion technologies.
在本研究中，基于密度泛函理论（DFT）采用第一性原理计算研究了LiInX₂（X = S，Te）化合物的结构、电子、光学和热电性质。采用了Wien2k软件包中实现的全势线性缀加平面波（FP-LAPW）方法，并应用广义梯度近似（GGA）和Tran-Blaha修正的Becke-Johnson（mBJ-GGA）近似来研究电子性质。结果表明，LiInS₂结晶为正交晶系，空间群为Pna21，而LiInTe₂结晶为四方晶系，空间群为I-42d。计算了晶格常数和弹性参数，与现有的实验值显示出良好的一致性。还评估了弹性性质，包括弹性常数、模量和力学稳定性判据，以深入了解化合物的结构稳健性和潜在的力学性能。电子能带结构计算表明，两种化合物都具有直接带隙，使用mBJ-GGA近似时，LiInS₂的值为3.61 eV，LiInTe₂的值为2.33 eV，这与实验测量值接近。进行了声子色散研究以验证两种化合物的动态稳定性。我们的研究结果表明，LiInX₂（X = S，Te）化合物具有合适的电子能带结构，在可见光和紫外范围内有强烈的光吸收，以及良好的热电特性。这些结果突出了它们作为光电器件和热电能量转换技术有前景的材料的潜力。
