Materials Data on SmAlFe by Materials Project
SmFeAl crystallizes in the orthorhombic Amm2 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 three equivalent Sm, five Fe, and seven Al atoms. There are one shorter (3.33 Å) and two longer (3.35 Å) Sm–Sm bond lengths. There are a spread of Sm–Fe bond distances ranging from 3.08–3.25 Å. There are a spread of Sm–Al bond distances ranging from 3.19–3.23 Å. In the second Sm site, Sm is bonded in a 12-coordinate geometry to four Sm, seven Fe, and five Al atoms. The Sm–Sm bond length is 3.13 Å. There are a spread of Sm–Fe bond distances ranging from 3.12–3.25 Å. There are a spread of Sm–Al bond distances ranging from 3.09–3.26 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded to six Sm and six Al atoms to form FeSm6Al6 cuboctahedra that share corners with four equivalent AlSm6Al2Fe4 cuboctahedra, corners with fourteen FeSm6Al6 cuboctahedra, edges with six FeSm6Al6 cuboctahedra, faces with four equivalent FeSm6Al2Fe4 cuboctahedra, and faces with fourteen AlSm6Al2Fe4 cuboctahedra. There are a spread of Fe–Al bond distances ranging from 2.69–2.78 Å. In the second Fe site, Fe is bonded to six Sm, four Fe, and two equivalent Al atoms to form distorted FeSm6Al2Fe4 cuboctahedra that share corners with eight FeSm6Al6 cuboctahedra, corners with ten AlSm6Al2Fe4 cuboctahedra, edges with two equivalent FeSm6Al2Fe4 cuboctahedra, edges with four equivalent AlSm6Al4Fe2 cuboctahedra, faces with eight AlSm6Al2Fe4 cuboctahedra, and faces with ten FeSm6Al6 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.59–2.90 Å. Both Fe–Al bond lengths are 2.66 Å. In the third Fe site, Fe is bonded to six Sm, four equivalent Fe, and two equivalent Al atoms to form distorted FeSm6Al2Fe4 cuboctahedra that share corners with six FeSm6Al6 cuboctahedra, corners with twelve AlSm6Al2Fe4 cuboctahedra, edges with six FeSm6Al6 cuboctahedra, faces with eight equivalent FeSm6Al2Fe4 cuboctahedra, and faces with ten AlSm6Al2Fe4 cuboctahedra. Both Fe–Al bond lengths are 2.66 Å. There are two inequivalent Al sites. In the first Al site, Al is bonded to six Sm, four Fe, and two equivalent Al atoms to form distorted AlSm6Al2Fe4 cuboctahedra that share corners with four equivalent AlSm6Al4Fe2 cuboctahedra, corners with eight FeSm6Al6 cuboctahedra, edges with six equivalent AlSm6Al2Fe4 cuboctahedra, faces with eight AlSm6Al2Fe4 cuboctahedra, and faces with twelve FeSm6Al6 cuboctahedra. Both Al–Al bond lengths are 2.84 Å. In the second Al site, Al is bonded to six Sm, two equivalent Fe, and four Al atoms to form distorted AlSm6Al4Fe2 cuboctahedra that share corners with eight AlSm6Al2Fe4 cuboctahedra, corners with ten FeSm6Al2Fe4 cuboctahedra, edges with two equivalent AlSm6Al4Fe2 cuboctahedra, edges with four equivalent FeSm6Al2Fe4 cuboctahedra, faces with eight FeSm6Al6 cuboctahedra, and faces with ten AlSm6Al2Fe4 cuboctahedra. There are one shorter (2.74 Å) and one longer (2.76 Å) Al–Al bond lengths.