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DOE OSTI · 1283804

Materials Data on Ho(FeSn)6 by Materials Project

Abstract

HoFe6Sn6 crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded to twelve Fe and eight Sn atoms to form distorted HoFe12Sn8 hexagonal bipyramids that share corners with four equivalent HoFe12Sn8 hexagonal bipyramids, faces with sixteen FeHo2Fe4Sn6 cuboctahedra, and faces with four HoFe12Sn8 hexagonal bipyramids. There are a spread of Ho–Fe bond distances ranging from 3.49–3.52 Å. There are a spread of Ho–Sn bond distances ranging from 3.02–3.17 Å. In the second Ho site, Ho is bonded to twelve Fe and eight Sn atoms to form distorted HoFe12Sn8 hexagonal bipyramids that share faces with eight FeHo2Fe4Sn6 cuboctahedra and faces with six HoFe12Sn8 hexagonal bipyramids. There are eight shorter (3.49 Å) and four longer (3.50 Å) Ho–Fe bond lengths. There are a spread of Ho–Sn bond distances ranging from 3.02–3.16 Å. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent Ho, four Fe, and six Sn atoms to form distorted FeHo2Fe4Sn6 cuboctahedra that share corners with eight FeHo2Fe4Sn6 cuboctahedra, edges with four FeHo2Fe4Sn6 cuboctahedra, faces with eight FeHo2Fe4Sn6 cuboctahedra, and faces with four equivalent HoFe12Sn8 hexagonal bipyramids. There are two shorter (2.71 Å) and two longer (2.72 Å) Fe–Fe bond lengths. There are a spread of Fe–Sn bond distances ranging from 2.72–2.83 Å. In the second Fe site, Fe is bonded to two equivalent Ho, four equivalent Fe, and six Sn atoms to form distorted FeHo2Fe4Sn6 cuboctahedra that share corners with six FeHo2Fe4Sn6 cuboctahedra, edges with three equivalent FeHo2Fe4Sn6 cuboctahedra, a faceface with one FeHo2Fe4Sn6 cuboctahedra, and faces with four HoFe12Sn8 hexagonal bipyramids. All Fe–Fe bond lengths are 2.71 Å. There are a spread of Fe–Sn bond distances ranging from 2.71–2.84 Å. In the third Fe site, Fe is bonded in a 12-coordinate geometry to two Ho, four Fe, and six Sn atoms. There are two shorter (2.71 Å) and one longer (2.72 Å) Fe–Fe bond lengths. There are a spread of Fe–Sn bond distances ranging from 2.70–2.83 Å. In the fourth Fe site, Fe is bonded to two equivalent Ho, four Fe, and six Sn atoms to form distorted FeHo2Fe4Sn6 cuboctahedra that share corners with ten FeHo2Fe4Sn6 cuboctahedra, edges with five FeHo2Fe4Sn6 cuboctahedra, faces with five FeHo2Fe4Sn6 cuboctahedra, and faces with four HoFe12Sn8 hexagonal bipyramids. There are a spread of Fe–Sn bond distances ranging from 2.69–2.83 Å. There are nine inequivalent Sn sites. In the first Sn site, Sn is bonded in a 12-coordinate geometry to three Ho and six Fe atoms. In the second Sn site, Sn is bonded in a 7-coordinate geometry to one Ho and six Fe atoms. In the third Sn site, Sn is bonded in a 6-coordinate geometry to six Fe atoms. In the fourth Sn site, Sn is bonded in a 8-coordinate geometry to one Ho, six Fe, and one Sn atom. The Sn–Ho bond length is 3.02 Å. Both Sn–Fe bond lengths are 2.84 Å. The Sn–Sn bond length is 2.92 Å. In the fifth Sn site, Sn is bonded in a 8-coordinate geometry to one Ho, six Fe, and one Sn atom. All Sn–Fe bond lengths are 2.83 Å. The Sn–Sn bond length is 2.92 Å. In the sixth Sn site, Sn is bonded in a 8-coordinate geometry to one Ho, six Fe, and one Sn atom. The Sn–Sn bond length is 2.92 Å. In the seventh Sn site, Sn is bonded in a 8-coordinate geometry to two equivalent Ho and six Fe atoms. In the eighth Sn site, Sn is bonded in a 12-coordinate geometry to three Ho and six Fe atoms. In the ninth Sn site, Sn is bonded in a 6-coordinate geometry to six Fe atoms.

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2020-05-02. Materials Data on Ho(FeSn)6 by Materials Project. https://doi.org/10.17188/1283804

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