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DOE OSTI · 1754830

Materials Data on Sm2Fe15Co2 by Materials Project

Abstract

Sm2Fe15Co2 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 10-coordinate geometry to seventeen Fe and two equivalent Co atoms. There are a spread of Sm–Fe bond distances ranging from 3.00–3.28 Å. Both Sm–Co bond lengths are 3.11 Å. In the second Sm site, Sm is bonded in a 10-coordinate geometry to fifteen Fe and four equivalent Co atoms. There are a spread of Sm–Fe bond distances ranging from 3.00–3.29 Å. There are two shorter (3.21 Å) and two longer (3.24 Å) Sm–Co bond lengths. There are ten inequivalent Fe sites. In the first Fe site, Fe is bonded in a 12-coordinate geometry to two Sm, nine Fe, and one Co atom. There are a spread of Fe–Fe bond distances ranging from 2.44–2.77 Å. The Fe–Co bond length is 2.65 Å. In the second Fe site, Fe is bonded in a 12-coordinate geometry to two Sm, nine Fe, and one Co atom. There are a spread of Fe–Fe bond distances ranging from 2.44–2.74 Å. The Fe–Co bond length is 2.53 Å. In the third Fe site, Fe is bonded in a 12-coordinate geometry to two Sm, eight Fe, and two equivalent Co atoms. There are a spread of Fe–Fe bond distances ranging from 2.45–2.76 Å. There are one shorter (2.53 Å) and one longer (2.66 Å) Fe–Co bond lengths. 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 equivalent CoSm3Fe9 cuboctahedra, corners with ten FeSm2Fe9Co cuboctahedra, edges with two equivalent CoSm3Fe9 cuboctahedra, edges with four FeSm3Fe9 cuboctahedra, faces with two equivalent CoSm3Fe9 cuboctahedra, and faces with eight FeSm2Fe9Co cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.45–2.61 Å. The Fe–Co bond length is 2.44 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 two equivalent CoSm3Fe9 cuboctahedra, corners with twelve FeSm2Fe9Co cuboctahedra, edges with two equivalent CoSm3Fe9 cuboctahedra, edges with four FeSm3Fe9 cuboctahedra, faces with two equivalent CoSm3Fe9 cuboctahedra, and faces with eight FeSm2Fe9Co cuboctahedra. There are two shorter (2.46 Å) and two longer (2.60 Å) Fe–Fe bond lengths. Both Fe–Co bond lengths are 2.44 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 2.40–2.67 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 2.62 Å. Both Fe–Co bond lengths are 2.63 Å. In the eighth Fe site, Fe is bonded to three Sm and nine Fe atoms to form FeSm3Fe9 cuboctahedra that share corners with fifteen FeSm2Fe9Co cuboctahedra, edges with four FeSm2Fe9Co cuboctahedra, edges with four equivalent CoSm3Fe9 cuboctahedra, faces with four equivalent CoSm3Fe9 cuboctahedra, and faces with six FeSm2Fe9Co cuboctahedra. Both Fe–Fe bond lengths are 2.48 Å. In the ninth Fe site, Fe is bonded to three Sm, eight Fe, and one Co atom to form FeSm3Fe8Co cuboctahedra that share corners with five equivalent CoSm3Fe9 cuboctahedra, corners with ten FeSm2Fe9Co cuboctahedra, an edgeedge with one CoSm3Fe9 cuboctahedra, edges with seven FeSm2Fe9Co cuboctahedra, faces with two equivalent CoSm3Fe9 cuboctahedra, and faces with eight FeSm2Fe9Co cuboctahedra. The Fe–Co bond length is 2.45 Å. In the tenth Fe site, Fe is bonded to three Sm, seven Fe, and two equivalent Co atoms to form FeSm3Fe7Co2 cuboctahedra that share corners with six equivalent CoSm3Fe9 cuboctahedra, corners with nine FeSm2Fe9Co cuboctahedra, edges with eight FeSm2Fe9Co cuboctahedra, faces with two equivalent CoSm3Fe9 cuboctahedra, and faces with eight FeSm2Fe9Co cuboctahedra. Both Fe–Co bond lengths are 2.47 Å. Co is bonded to three Sm and nine Fe atoms to form distorted CoSm3Fe9 cuboctahedra that share corners with two equivalent CoSm3Fe9 cuboctahedra, corners with thirteen FeSm2Fe9Co cuboctahedra, edges with two equivalent CoSm3Fe9 cuboctahedra, edges with six FeSm2Fe9Co cuboctahedra, faces with two equivalent CoSm3Fe9 cuboctahedra, and faces with eight FeSm2Fe9Co cuboctahedra.

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2020-06-04. Materials Data on Sm2Fe15Co2 by Materials Project. https://doi.org/10.17188/1754830

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