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DOE OSTI · 1712046

Materials Data on ThScFe6 by Materials Project

Abstract

ThScFe6 crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent Th sites. In the first Th site, Th is bonded in a 12-coordinate geometry to three equivalent Sc and twelve Fe atoms. All Th–Sc bond lengths are 3.16 Å. There are a spread of Th–Fe bond distances ranging from 2.91–2.99 Å. In the second Th site, Th is bonded in a distorted hexagonal planar geometry to one Sc and eighteen Fe atoms. The Th–Sc bond length is 3.44 Å. There are six shorter (2.91 Å) and twelve longer (3.26 Å) Th–Fe bond lengths. In the third Th site, Th is bonded in a 6-coordinate geometry to eighteen Fe atoms. There are a spread of Th–Fe bond distances ranging from 2.91–3.31 Å. There are three inequivalent Sc sites. In the first Sc site, Sc is bonded in a 12-coordinate geometry to twelve Fe atoms. There are a spread of Sc–Fe bond distances ranging from 2.89–2.96 Å. In the second Sc site, Sc is bonded in a 12-coordinate geometry to four Th and twelve Fe atoms. There are a spread of Sc–Fe bond distances ranging from 2.87–3.06 Å. In the third Sc site, Sc is bonded in a 12-coordinate geometry to twelve Fe atoms. There are a spread of Sc–Fe bond distances ranging from 2.89–2.96 Å. There are ten inequivalent Fe sites. In the first Fe site, Fe is bonded to three equivalent Th and nine Fe atoms to form distorted FeTh3Fe9 cuboctahedra that share corners with fifteen FeSc6Fe6 cuboctahedra, edges with six equivalent FeTh3Fe9 cuboctahedra, and faces with nineteen FeTh3Sc3Fe6 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.53–2.91 Å. In the second Fe site, Fe is bonded to three equivalent Th and nine Fe atoms to form distorted FeTh3Fe9 cuboctahedra that share corners with eighteen FeTh3Sc3Fe6 cuboctahedra, edges with six equivalent FeTh3Fe9 cuboctahedra, and faces with twenty-two FeSc6Fe6 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.50–2.91 Å. In the third Fe site, Fe is bonded to six Sc and six Fe atoms to form FeSc6Fe6 cuboctahedra that share corners with eighteen FeTh3Fe9 cuboctahedra, edges with six equivalent FeSc6Fe6 cuboctahedra, and faces with nineteen FeTh3Fe9 cuboctahedra. All Fe–Fe bond lengths are 2.45 Å. In the fourth Fe site, Fe is bonded to three equivalent Th, three equivalent Sc, and six Fe atoms to form FeTh3Sc3Fe6 cuboctahedra that share corners with fifteen FeTh3Fe9 cuboctahedra, edges with six equivalent FeTh3Sc3Fe6 cuboctahedra, and faces with twenty FeTh3Fe9 cuboctahedra. There are three shorter (2.48 Å) and three longer (2.53 Å) Fe–Fe bond lengths. In the fifth Fe site, Fe is bonded to two equivalent Th, three Sc, and seven Fe atoms to form FeTh2Sc3Fe7 cuboctahedra that share corners with nineteen FeTh3Fe9 cuboctahedra, edges with eight FeTh2Sc3Fe7 cuboctahedra, and faces with seventeen FeTh3Fe9 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.51–2.56 Å. In the sixth Fe site, Fe is bonded to three Th, two equivalent Sc, and seven Fe atoms to form distorted FeTh3Sc2Fe7 cuboctahedra that share corners with twenty-one FeTh3Fe9 cuboctahedra, edges with eight FeTh2Sc3Fe7 cuboctahedra, and faces with twenty FeTh3Fe9 cuboctahedra. There are two shorter (2.51 Å) and three longer (2.53 Å) Fe–Fe bond lengths. In the seventh Fe site, Fe is bonded to two equivalent Th, three Sc, and seven Fe atoms to form FeTh2Sc3Fe7 cuboctahedra that share corners with twenty-one FeTh3Fe9 cuboctahedra, edges with eight FeTh2Sc3Fe7 cuboctahedra, and faces with twenty FeTh3Fe9 cuboctahedra. There are two shorter (2.51 Å) and three longer (2.53 Å) Fe–Fe bond lengths. In the eighth Fe site, Fe is bonded to four Th, one Sc, and seven Fe atoms to form distorted FeTh4ScFe7 cuboctahedra that share corners with nineteen FeTh3Fe9 cuboctahedra, edges with eight FeTh4ScFe7 cuboctahedra, and faces with seventeen FeTh3Fe9 cuboctahedra. There are three shorter (2.51 Å) and two longer (2.53 Å) Fe–Fe bond lengths. In the ninth Fe site, Fe is bonded to three equivalent Th and nine Fe atoms to form a mixture of distorted edge, face, and corner-sharing FeTh3Fe9 cuboctahedra. In the tenth Fe site, Fe is bonded in a 12-coordinate geometry to three equivalent Th and nine Fe atoms.

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2020-06-04. Materials Data on ThScFe6 by Materials Project. https://doi.org/10.17188/1712046

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