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DOE OSTI · 1746961

Materials Data on Sm2Ga2Fe15C2 by Materials Project

Abstract

Sm2Fe15Ga2C2 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 bent 120 degrees geometry to nine Fe and two equivalent C atoms. There are a spread of Sm–Fe bond distances ranging from 3.10–3.44 Å. Both Sm–C bond lengths are 2.52 Å. In the second Sm site, Sm is bonded in a distorted bent 120 degrees geometry to nine Fe and two equivalent C atoms. There are a spread of Sm–Fe bond distances ranging from 3.06–3.49 Å. Both Sm–C bond lengths are 2.55 Å. There are ten inequivalent Fe sites. In the first Fe site, Fe is bonded in a 2-coordinate geometry to one Sm, eleven Fe, and two equivalent Ga atoms. There are a spread of Fe–Fe bond distances ranging from 2.40–2.79 Å. Both Fe–Ga bond lengths are 2.68 Å. In the second 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 2.57–2.77 Å. In the third Fe site, Fe is bonded in a single-bond geometry to six Fe and one C atom. There are a spread of Fe–Fe bond distances ranging from 2.45–2.61 Å. The Fe–C bond length is 1.85 Å. In the fourth Fe site, Fe is bonded in a single-bond geometry to six Fe and one C atom. There are a spread of Fe–Fe bond distances ranging from 2.48–2.55 Å. The Fe–C bond length is 1.84 Å. In the fifth Fe site, Fe is bonded to two Sm, nine Fe, and one Ga atom to form distorted FeSm2GaFe9 cuboctahedra that share corners with eight FeSm2GaFe9 cuboctahedra, corners with four equivalent CSm2GaFe3 octahedra, edges with three FeSm2GaFe9 cuboctahedra, edges with two equivalent CSm2GaFe3 octahedra, and faces with nine FeSm2GaFe9 cuboctahedra. The corner-sharing octahedra tilt angles range from 22–30°. There are a spread of Fe–Fe bond distances ranging from 2.45–2.71 Å. The Fe–Ga bond length is 2.56 Å. In the sixth Fe site, Fe is bonded to two Sm, nine Fe, and one Ga atom to form distorted FeSm2GaFe9 cuboctahedra that share corners with eight FeSm2GaFe9 cuboctahedra, corners with two equivalent CSm2GaFe3 octahedra, edges with four FeSm2GaFe9 cuboctahedra, faces with eight FeSm2GaFe9 cuboctahedra, and faces with two equivalent CSm2GaFe3 octahedra. The corner-sharing octahedra tilt angles range from 40–47°. There are a spread of Fe–Fe bond distances ranging from 2.43–2.46 Å. The Fe–Ga bond length is 2.50 Å. In the seventh Fe site, Fe is bonded to two Sm, eight Fe, and two equivalent Ga atoms to form distorted FeSm2Ga2Fe8 cuboctahedra that share corners with fourteen FeSm2GaFe9 cuboctahedra, edges with two FeSm3Ga2Fe7 cuboctahedra, faces with ten FeSm2GaFe9 cuboctahedra, and faces with four equivalent CSm2GaFe3 octahedra. Both Fe–Fe bond lengths are 2.47 Å. Both Fe–Ga bond lengths are 2.51 Å. In the eighth Fe site, Fe is bonded to three Sm, seven Fe, and two equivalent Ga atoms to form distorted FeSm3Ga2Fe7 cuboctahedra that share corners with eleven FeSm2GaFe9 cuboctahedra, corners with four equivalent CSm2GaFe3 octahedra, edges with four FeSm2GaFe9 cuboctahedra, faces with eight FeSm2GaFe9 cuboctahedra, and faces with two equivalent CSm2GaFe3 octahedra. The corner-sharing octahedra tilt angles range from 66–70°. Both Fe–Ga bond lengths are 2.59 Å. In the ninth Fe site, Fe is bonded in a single-bond geometry to five Fe and one C atom. The Fe–Fe bond length is 2.54 Å. The Fe–C bond length is 1.86 Å. In the tenth Fe site, Fe is bonded to three Sm and nine Fe atoms to form distorted FeSm3Fe9 cuboctahedra that share corners with eleven FeSm2GaFe9 cuboctahedra, corners with four equivalent CSm2GaFe3 octahedra, edges with four FeSm2GaFe9 cuboctahedra, faces with eight FeSm2GaFe9 cuboctahedra, and faces with two equivalent CSm2GaFe3 octahedra. The corner-sharing octahedra tilt angles range from 62–66°. Ga is bonded in a single-bond geometry to five Fe and one C atom. The Ga–C bond length is 2.16 Å. C is bonded to two Sm, three Fe, and one Ga atom to form CSm2GaFe3 octahedra that share corners with ten FeSm2GaFe9 cuboctahedra, corners with two equivalent CSm2GaFe3 octahedra, edges with two equivalent FeSm2GaFe9 cuboctahedra, and faces with six FeSm2GaFe9 cuboctahedra. The corner-sharing octahedra tilt angles range from 62–64°.

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2020-06-04. Materials Data on Sm2Ga2Fe15C2 by Materials Project. https://doi.org/10.17188/1746961

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