Density functional theory’s (DFT) full potential linearized augmented plane wave method has been used to explore the structural and optoelectronic properties of bismuth-based tetragonal BiOCl, BiOBr and BiOI semiconductors. The generalized gradient approximation (GGA) has been used for structural optimization to approximate lattice constants and bulk moduli, which are found to be consistent with the current literature. Electronic band structures are computed using the modified Becke and Johnson generalized gradient approximation (mBJ) and within the Engel and Vosko generalized gradient approximation (EV-GGA), respectively. Based on the band structure analysis, these functional materials are indirect bandgap semiconductors with a wide range of potential applications. In addition, optical properties are also computed within mBJ and found to be appealing for optoelectronics and photocatalysis.

中文翻译：

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卤氧化铋的结构和光电性质的理论研究

密度泛函理论 (DFT) 的全势线性化增强平面波方法已被用于探索铋基四方 BiOCl、BiOBr 和 BiOI 半导体的结构和光电特性。广义梯度近似（GGA）已被用于结构优化以近似晶格常数和体积模量，这与当前的文献一致。电子能带结构分别使用改进的 Becke 和 Johnson 广义梯度近似 (mBJ) 以及 Engel 和 Vosko 广义梯度近似 (EV-GGA) 计算。基于能带结构分析，这些功能材料是具有广泛潜在应用的间接带隙半导体。此外，