Abstract Structural parameters, elastic constants, electronic structure and optical functions of the ternary tetragonal chalcogenides KAlTe2 and KInTe2 are predicted via ab initio calculations. The calculated structural parameters and interatomic distances agree very well with the existing experimental results. The computed band structures show that the two studied materials are semiconductors with indirect band-gaps. The computed partial density of states diagrams, charges transfer and distribution of charge density show that the interatomic bonds are mainly of a covalent nature. The calculated elastic constants indicate that the title compounds are mechanically stable and elastically strongly anisotropic. The calculated optical spectra for both explored compounds exhibit a significant optical anisotropy. Both compounds have a low absorption in the visible range compared to the infrared (IR) domain. The refractive index spectrum of KInTe2 is more anisotropic than that of KAlTe2.

中文翻译：

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三元四方碲化物 KBTe2 (B = Al, In) 的结构、弹性、电子和光学特性的理论研究

摘要 三元四方硫族化物KAlTe2 和KInTe2 的结构参数、弹性常数、电子结构和光学函数是通过从头计算来预测的。计算的结构参数和原子间距离与现有的实验结果非常吻合。计算的能带结构表明，所研究的两种材料是具有间接带隙的半导体。计算的部分状态密度图、电荷转移和电荷密度分布表明原子间键主要具有共价性质。计算出的弹性常数表明标题化合物具有机械稳定性和弹性强各向异性。两种探索化合物的计算光谱都表现出显着的光学各向异性。与红外 (IR) 域相比，这两种化合物在可见光范围内的吸收率较低。KInTe2 的折射率谱比 KAlTe2 的折射率谱更具各向异性。