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DOE OSTI · 1759218

Materials Data on Sm2Fe14B by Materials Project

Abstract

Sm2Fe14B crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. there are two inequivalent Sm sites. In the first Sm site, Sm is bonded in a 12-coordinate geometry to sixteen Fe and two equivalent B atoms. There are a spread of Sm–Fe bond distances ranging from 3.03–3.23 Å. Both Sm–B bond lengths are 3.26 Å. In the second Sm site, Sm is bonded in a 1-coordinate geometry to sixteen Fe and one B atom. There are a spread of Sm–Fe bond distances ranging from 3.05–3.36 Å. The Sm–B bond length is 2.87 Å. There are six inequivalent Fe sites. In the first Fe site, Fe is bonded to two Sm and ten Fe atoms to form a mixture of distorted corner, edge, and face-sharing FeSm2Fe10 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.38–2.64 Å. In the second Fe site, Fe is bonded to four Sm and eight Fe atoms to form a mixture of corner and face-sharing FeSm4Fe8 cuboctahedra. All Fe–Fe bond lengths are 2.56 Å. In the third Fe site, Fe is bonded in a distorted L-shaped geometry to two equivalent Sm, four Fe, and two equivalent B atoms. There are two shorter (2.50 Å) and two longer (2.76 Å) Fe–Fe bond lengths. Both Fe–B bond lengths are 2.07 Å. In the fourth Fe site, Fe is bonded in a 2-coordinate geometry to two Sm and twelve Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.63–2.77 Å. In the fifth Fe site, Fe is bonded in a distorted single-bond geometry to two Sm, seven Fe, and one B atom. The Fe–Fe bond length is 2.58 Å. The Fe–B bond length is 2.08 Å. In the sixth Fe site, Fe is bonded to three Sm and nine Fe atoms to form distorted FeSm3Fe9 cuboctahedra that share corners with fourteen FeSm2Fe10 cuboctahedra, edges with three FeSm3Fe9 cuboctahedra, and faces with twelve FeSm2Fe10 cuboctahedra. The Fe–Fe bond length is 2.41 Å. B is bonded in a 6-coordinate geometry to three Sm and six Fe atoms.

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2020-09-03. Materials Data on Sm2Fe14B by Materials Project. https://doi.org/10.17188/1759218

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