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arXiv · 1908.02926

Cerium as a possible stabilizer of ThMn$_{12}$-type iron-based compounds: A first-principles study

Yosuke Harashima·Taro Fukazawa·Takashi Miyake
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Abstract

The structural stability of CeFe$_{12}$ is investigated by using first-principles calculation. The formation energies of CeFe$_{12}$ relative to the Ce$_{2}$Fe$_{17}$ + bcc-Fe phase and to the CeFe$_{2}$ + bcc-Fe phase are calculated with the assumptions of trivalency and tetravalency for Ce. Those values are compared with corresponding results in $R$Fe$_{12}$ for $R=$ Nd, Sm, and Zr. Our results suggest that the tetravalent Ce is a promising stabilizer of the ThMn$_{12}$ structure. We also show that the stabilizing effect of an element depends as much on the valency as on the size of the $R$ element by investigating $R$Fe$_{12}$ where $R$ is assumed to have a hypothetical valency on the basis of first-principles calculation.

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Yosuke Harashima, Taro Fukazawa, Takashi Miyake. 2019-08-08. Cerium as a possible stabilizer of ThMn$_{12}$-type iron-based compounds: A first-principles study. https://doi.org/10.1016/j.scriptamat.2020.01.004

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