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DOE OSTI · 1697058

Materials Data on Sm2V(Fe8N)2 by Materials Project

Abstract

Sm2V(Fe8N)2 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 bent 120 degrees geometry to eight Fe and two equivalent N atoms. There are a spread of Sm–Fe bond distances ranging from 3.09–3.38 Å. Both Sm–N bond lengths are 2.49 Å. In the second Sm site, Sm is bonded in a bent 120 degrees geometry to one V, eight Fe, and two equivalent N atoms. The Sm–V bond length is 3.20 Å. There are a spread of Sm–Fe bond distances ranging from 3.10–3.39 Å. Both Sm–N bond lengths are 2.50 Å. V is bonded in a 1-coordinate geometry to one Sm and thirteen Fe atoms. There are a spread of V–Fe bond distances ranging from 2.29–2.76 Å. There are ten inequivalent Fe sites. In the first Fe site, Fe is bonded in a single-bond geometry to one V, four Fe, and one N atom. There are a spread of Fe–Fe bond distances ranging from 2.44–2.58 Å. The Fe–N bond length is 1.89 Å. In the second Fe site, Fe is bonded in a single-bond geometry to one V, four Fe, and one N atom. There are a spread of Fe–Fe bond distances ranging from 2.44–2.61 Å. The Fe–N bond length is 1.89 Å. In the third Fe site, Fe is bonded to two Sm, one V, and nine Fe atoms to form distorted FeSm2VFe9 cuboctahedra that share corners with eight FeSm2VFe9 cuboctahedra, corners with four equivalent NSm2Fe4 octahedra, edges with three FeSm2VFe9 cuboctahedra, edges with two equivalent NSm2Fe4 octahedra, and faces with nine FeSm2VFe9 cuboctahedra. The corner-sharing octahedra tilt angles range from 25–28°. There are a spread of Fe–Fe bond distances ranging from 2.46–2.75 Å. In the fourth Fe site, Fe is bonded in a single-bond geometry to one V, four Fe, and one N atom. There are a spread of Fe–Fe bond distances ranging from 2.48–2.57 Å. The Fe–N bond length is 1.93 Å. In the fifth Fe site, Fe is bonded to three Sm, one V, and eight Fe atoms to form FeSm3VFe8 cuboctahedra that share corners with eleven FeSm2VFe9 cuboctahedra, corners with four equivalent NSm2Fe4 octahedra, edges with four FeSm3Fe9 cuboctahedra, faces with eight FeSm2VFe9 cuboctahedra, and faces with two equivalent NSm2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 64–70°. There are two shorter (2.46 Å) and two longer (2.55 Å) Fe–Fe bond lengths. In the sixth Fe site, Fe is bonded in a single-bond geometry to four Fe and one N atom. There are one shorter (2.47 Å) and one longer (2.48 Å) Fe–Fe bond lengths. The Fe–N bond length is 1.93 Å. In the seventh Fe site, Fe is bonded to three Sm and nine Fe atoms to form FeSm3Fe9 cuboctahedra that share corners with eleven FeSm2VFe9 cuboctahedra, corners with four equivalent NSm2Fe4 octahedra, edges with four FeSm3VFe8 cuboctahedra, faces with eight FeSm2VFe9 cuboctahedra, and faces with two equivalent NSm2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 63–69°. There are two shorter (2.47 Å) and one longer (2.69 Å) Fe–Fe bond lengths. In the eighth Fe site, Fe is bonded to two Sm, one V, and nine Fe atoms to form distorted FeSm2VFe9 cuboctahedra that share corners with eight FeSm2VFe9 cuboctahedra, corners with two equivalent NSm2Fe4 octahedra, edges with four FeSm2VFe9 cuboctahedra, faces with eight FeSm2VFe9 cuboctahedra, and faces with two equivalent NSm2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 44–46°. The Fe–Fe bond length is 2.66 Å. In the ninth Fe site, Fe is bonded to two Sm, one V, and nine Fe atoms to form distorted FeSm2VFe9 cuboctahedra that share corners with fourteen FeSm2VFe9 cuboctahedra, edges with two FeSm3Fe9 cuboctahedra, faces with ten FeSm2VFe9 cuboctahedra, and faces with four equivalent NSm2Fe4 octahedra. The Fe–Fe bond length is 2.70 Å. In the tenth Fe site, Fe is bonded in a distorted single-bond geometry to one V and six Fe atoms. N is bonded to two Sm and four Fe atoms to form NSm2Fe4 octahedra that share corners with ten FeSm2VFe9 cuboctahedra, corners with two equivalent NSm2Fe4 octahedra, edges with two equivalent FeSm2VFe9 cuboctahedra, and faces with six FeSm3Fe9 cuboctahedra. The corner-sharing octahedral tilt angles are 61°.

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2020-06-04. Materials Data on Sm2V(Fe8N)2 by Materials Project. https://doi.org/10.17188/1697058

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