This study presents the synthesis of nano-crystalline spinel ferrites AFeO (A = Co, Ni, Zn, and Mg), through the sol-gel method, yielding crystallite sizes ranging from 12 to 28 nm. The variation in IR and Raman spectra due to M-O-M bonding supports the variation in lattice parameters. The magnetization measurements revealed that CoFeO has a high saturation magnetization of ∼55 emu/g and coercivity of ∼1350 Oe, while ZnFeO exhibited saturation magnetization value of ∼8 emu/g and coercivity of ∼16 Oe. In addition, the electronic structure calculated using DFT, which corroborated the antiparallel alignment of Fe ions in the tetrahedral and octahedral sites, validating the measured magnetic moments. Notably, the CoFeO ferrite exhibited a higher squareness ratio than other ferrites, signifying its suitability as a magnetic material for audio-video recording.

中文翻译：

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揭示 AFe2O4（A = Co、Ni、Zn 和 Mg）的电子结构和磁性：将实验与 DFT 研究相结合

本研究介绍了通过溶胶-凝胶法合成纳米晶尖晶石铁氧体 AFeO（A = Co、Ni、Zn 和 Mg），产生的微晶尺寸范围为 12 至 28 nm。MOM 键合导致的红外和拉曼光谱的变化支持了晶格参数的变化。磁化强度测量表明，CoFeO具有~55 emu/g的高饱和磁化强度和~1350 Oe的矫顽力，而ZnFeO表现出~8 emu/g的饱和磁化强度值和~16 Oe的矫顽力。此外，使用DFT计算的电子结构证实了四面体和八面体位点中Fe离子的反平行排列，验证了测量的磁矩。值得注意的是，CoFeO铁氧体表现出比其他铁氧体更高的矩形比，这表明它适合作为音频视频记录的磁性材料。