The structural, electronic, magnetic, optical and thermoelectric properties of anti‐fluorite Cs₂NbI₆ were investigated using full potential augmented plane wave method of density functional theory. Structurally, Cs₂NbI₆ was found to be cubic in ground state from values of tolerance factor (1.04) and formation energy (−22.3 eV). While, it's ferromagnetic nature was predicted from volume optimization process. In spin down channel, the compound was explored as indirect band gap (E_g(Γ‐X) = 1.97 eV) semiconductor, while it changes to metallic in upper spin channel. Nb‐d and I‐p states were exposed as the main cause of spin dependent electronic nature (half‐metallicity). The origin of magnetism in Cs₂NbI₆ was explained on basis of crystal field theory. The calculated magnetic moment (1.001 μ_B) was found in reasonable agreement with experimental value. The optimum absorption and optical conductivity spectra in semiconductor state explored Cs₂NbI₆ as suitable for optoelectronic devices. Furthermore, the transport properties were calculated using BoltzTrap code. The nature of carriers was predicted as n type from negative values of Seebeck coefficients. Where, the figure of merit (ZT) was found to increase up to 0.85 at 900 K. The present work not only explores Cs₂NbI₆ as potential optoelectronic and thermoelectric material, but can also inspire more experimental research on this important compound.

中文翻译：

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抗萤石Cs2NbI6通过其结构，电子，磁性，光学和热电性质的重要性

使用密度泛函理论的全势增强平面波方法研究了抗萤石Cs ₂ NbI ₆的结构，电子，磁性，光学和热电性质。在结构上，从公差系数（1.04）和地层能量（-22.3 eV）的值中发现Cs ₂ NbI ₆在基态下为立方。同时，它的铁磁性质是通过体积优化过程预测的。在向下旋转通道中，该化合物被研究为间接带隙（E _g（Γ-X） = 1.97 eV）半导体，而在上方旋转通道中变为金属。NB- d和I p状态被暴露为自旋相关电子性质（半金属性）的主要原因。根据晶体场论解释了Cs ₂ NbI _6中的磁性起源。所计算出的磁矩（1.001 μ_乙）与实验值合理的协议被发现。半导体状态下的最佳吸收光谱和光导光谱表明，Cs ₂ NbI ₆适合用于光电器件。此外，使用BoltzTrap代码计算传输性质。根据塞贝克系数的负值，将载流子的性质预测为n型。哪里发现品质因数（ZT）在900 K时增加到0.85。本研究不仅探讨Cs₂ NbI ₆作为潜在的光电和热电材料，但也可以激发对该重要化合物的更多实验研究。