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arXiv · 2004.10948

Covalency a Pathway for Achieving High Magnetisation in $TMFe_2O_4$ Compounds

M. H. N. Assadi·H. Katayama-Yoshida
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Abstract

The interplay between covalency and magnetism is non-trivial and can be harnessed for designing new functional magnetic materials. Based on a survey using density functional calculations, we show that $TM\unicode{x2013}O$ bond covalency can increase the total magnetic moment of spinel compounds of $TMFe_2O_4$ composition ($TM = V-Ni, Nb-Pd$) which are isomorphic to the much-researched magnetite. Accordingly, $PdFe_2O_4$ was found to exhibit the highest magnetic moment of 7.809 ${\mu}_B$ per formula unit which is approximately twice that of $Fe_3O_4$ with $T_c$ predicted to be well above ambient. We further propose a practical method for synthesising $PdFe_2O_4$.

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M. H. N. Assadi, H. Katayama-Yoshida. 2020-04-23. Covalency a Pathway for Achieving High Magnetisation in $TMFe_2O_4$ Compounds. https://doi.org/10.7566/jpsj.88.044706

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