Abstract

The electronic, magnetic, and optical properties of MnGa₂O₄ in the structure of the normal and inverse spinels are subjected to an ab initio investigation and comparison. The generalized gradient approximation (GGA) predicts that the normal MnGa₂O₄ spinel is a semiconductor with a bandgap of about 0.7 eV, and a bandgap in the structure of the inverse spinel appears only in terms of the GGA + U approach. A simple exchange interaction model is used to calculate exchange integrals. In both structure types, MnGa₂O₄ exhibits antiferromagnetic behavior, and the normal structure is energetically favorable. The inverse spinel becomes energetically favorable only when a negative pressure is applied. The absorption spectra of the normal spinel are found to have a spectral window at a wavelength larger than 450 nm.

中文翻译：

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从头开始研究正，反MnGa 2 O 4尖晶石的结构，磁性和光学性质之间的关系

摘要

对正，反尖晶石结构中的MnGa ₂ O ₄的电子，磁性和光学性质进行从头开始的研究和比较。广义梯度近似（GGA）预测正常的MnGa ₂ O ₄尖晶石是带隙约为0.7 eV的半导体，反尖晶石结构中的带隙仅在GGA + U方法方面出现。一个简单的交换交互模型用于计算交换积分。在两种结构类型中，MnGa ₂ O ₄表现出反铁磁行为，并且正常结构在能量上有利。仅当施加负压时，反尖晶石在能量上变得有利。发现普通尖晶石的吸收光谱在大于450nm的波长处具有光谱窗口。