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DOE OSTI · 1676952

Materials Data on Sm2Fe15Co2C3 by Materials Project

Abstract

Sm2Fe15Co2C3 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent Sm sites. In the first Sm site, Sm is bonded in a distorted trigonal planar geometry to four Fe and three C atoms. There are a spread of Sm–Fe bond distances ranging from 3.12–3.37 Å. There are two shorter (2.52 Å) and one longer (2.53 Å) Sm–C bond lengths. In the second Sm site, Sm is bonded in a distorted trigonal planar geometry to four Fe and three C atoms. There are one shorter (3.13 Å) and three longer (3.36 Å) Sm–Fe bond lengths. There are two shorter (2.51 Å) and one longer (2.52 Å) Sm–C bond lengths. There are ten inequivalent Fe sites. In the first Fe site, Fe is bonded in a single-bond geometry to four Fe and one C atom. There are a spread of Fe–Fe bond distances ranging from 2.45–2.74 Å. The Fe–C bond length is 1.89 Å. In the second Fe site, Fe is bonded in a single-bond geometry to four Fe and one C atom. There are a spread of Fe–Fe bond distances ranging from 2.44–2.74 Å. The Fe–C bond length is 1.88 Å. In the third Fe site, Fe is bonded in a single-bond geometry to four Fe and one C atom. There are a spread of Fe–Fe bond distances ranging from 2.44–2.75 Å. The Fe–C bond length is 1.89 Å. In the fourth Fe site, Fe is bonded to two Sm, nine Fe, and one Co atom to form distorted FeSm2Fe9Co cuboctahedra that share corners with four FeSm2Fe9Co cuboctahedra, corners with two equivalent CSm2Fe3Co octahedra, faces with four FeSm2Fe9Co cuboctahedra, and faces with four CSm2Fe3Co octahedra. The corner-sharing octahedra tilt angles range from 45–46°. There are a spread of Fe–Fe bond distances ranging from 2.48–2.67 Å. The Fe–Co bond length is 2.47 Å. In the fifth Fe site, Fe is bonded to two Sm, eight Fe, and two equivalent Co atoms to form distorted FeSm2Fe8Co2 cuboctahedra that share corners with four equivalent FeSm2Fe9Co cuboctahedra, corners with two equivalent CSm2Fe4 octahedra, faces with four equivalent FeSm2Fe9Co cuboctahedra, and faces with four equivalent CSm2Fe3Co octahedra. The corner-sharing octahedral tilt angles are 45°. There are two shorter (2.49 Å) and two longer (2.67 Å) Fe–Fe bond lengths. Both Fe–Co bond lengths are 2.47 Å. In the sixth Fe site, Fe is bonded in a 2-coordinate geometry to one Sm and thirteen Fe atoms. There are a spread of Fe–Fe bond distances ranging from 2.37–2.66 Å. In the seventh Fe site, Fe is bonded in a 4-coordinate geometry to one Sm, eleven Fe, and two equivalent Co atoms. The Fe–Fe bond length is 2.66 Å. Both Fe–Co bond lengths are 2.65 Å. In the eighth Fe site, Fe is bonded in a single-bond geometry to three Fe and one C atom. The Fe–C bond length is 1.91 Å. In the ninth Fe site, Fe is bonded in a single-bond geometry to three Fe and one C atom. The Fe–C bond length is 1.90 Å. In the tenth Fe site, Fe is bonded in a single-bond geometry to three Fe and one C atom. The Fe–C bond length is 1.91 Å. Co is bonded in a single-bond geometry to three Fe and one C atom. The Co–C bond length is 1.88 Å. There are two inequivalent C sites. In the first C site, C is bonded to two Sm, three Fe, and one Co atom to form CSm2Fe3Co octahedra that share corners with two equivalent FeSm2Fe9Co cuboctahedra, corners with four CSm2Fe3Co octahedra, and faces with four FeSm2Fe9Co cuboctahedra. The corner-sharing octahedra tilt angles range from 60–61°. In the second C site, C is bonded to two Sm and four Fe atoms to form CSm2Fe4 octahedra that share corners with two equivalent FeSm2Fe8Co2 cuboctahedra, corners with four equivalent CSm2Fe3Co octahedra, and faces with four equivalent FeSm2Fe9Co cuboctahedra. The corner-sharing octahedral tilt angles are 60°.

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2020-05-02. Materials Data on Sm2Fe15Co2C3 by Materials Project. https://doi.org/10.17188/1676952

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