Abstract The structural, electronic, magnetic, thermoelectric and thermodynamic properties of Ba3MnNb2O9 have been investigated using the full-potential linearized augmented plane wave method. Besides, the thermodynamic properties of the materials of interest have been studied using the quasi-harmonic Debye model accommodating the lattice vibrations effects. A comparison between the computed crystal structure parameters and the corresponding experimental counterparts shows a very good agreement between them. The band structures (BS) and density of states (DOS) ensure the magnetic semiconductors nature of the studied complex perovskite. Moreover, the thermoelectric properties of this compound were studied using the transport quasi-classical theory. The effects of pressure and temperature on the studied properties are found to be highly effective in tuning some of the macroscopic properties of the compound in question.

中文翻译：

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复合钙钛矿 Ba3MnNb2O9 热电和热力学性质的第一性原理研究

摘要 使用全电位线性化增强平面波方法研究了 Ba3MnNb2O9 的结构、电子、磁、热电和热力学性质。此外，使用适应晶格振动效应的准谐波德拜模型研究了感兴趣材料的热力学性质。计算出的晶体结构参数与相应的实验对应物之间的比较表明它们之间非常吻合。能带结构 (BS) 和态密度 (DOS) 确保所研究的复合钙钛矿的磁性半导体性质。此外，使用输运准经典理论研究了该化合物的热电性质。