Double perovskites are usually strongly correlated electronic systems that offer many multifunctional properties and are most commonly formed in the monoclinic crystal phase. In this study, we used a first-principles DFT approach in studying the optical and magnetic aspects of Ba2MMoO6 ([Formula: see text], Fe) double perovskite structures in a new monoclinic phase in both their pure and oxygen-deficient form and compared it to their natural cubic phase. The structural parameters of our structures were consistent with the available experimental data of the similar Ca2MMoO6 compounds. The optical analysis suggests a high dielectric function for both compounds in their pure and defected state. The addition of defects increases the absorption of photons near the visible spectra. We also found the structures to be half-metallic, with a reduction of magnetic strength and half-metallic gaps when oxygen defects are added to the structure. These features suggest a possible application in the optoelectronics and spintronics industry, even when the crystal structures have oxygen vacancies.

中文翻译：

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单斜晶相中缺氧 Ba2MMoO6−μ (M=Mn, Fe and μ=0, 0.5, 1.0) 的光学和磁性：第一性原理研究

双钙钛矿通常是强相关的电子系统，具有许多多功能特性，最常见于单斜晶相。在这项研究中，我们使用第一性原理 DFT 方法来研究 Ba 的光学和磁性方面2MMoO6（[公式：见正文]，Fe）双钙钛矿结构在新的单斜晶相中以纯和缺氧形式存在，并将其与天然立方相进行比较。我们结构的结构参数与类似Ca的可用实验数据一致2MMoO6化合物。光学分析表明，这两种化合物在纯态和缺陷态都具有高介电功能。缺陷的添加增加了可见光谱附近光子的吸收。我们还发现这些结构是半金属的，当结构中添加氧缺陷时，磁强度和半金属间隙会降低。这些特征表明在光电子学和自旋电子学工业中的可能应用，即使晶体结构具有氧空位也是如此。