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DOE OSTI · 1651527

Materials Data on Ho2Ga3(Fe7C)2 by Materials Project

Abstract

Ho2Ga3(Fe7C)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. Ho is bonded in a distorted bent 120 degrees geometry to six Fe, three Ga, and two equivalent C atoms. There are a spread of Ho–Fe bond distances ranging from 3.03–3.31 Å. There are two shorter (3.32 Å) and one longer (3.38 Å) Ho–Ga bond lengths. Both Ho–C bond lengths are 2.51 Å. There are five inequivalent Fe sites. In the first Fe site, Fe is bonded in a 1-coordinate geometry to one Ho, ten Fe, and three Ga atoms. There are a spread of Fe–Fe bond distances ranging from 2.32–2.78 Å. There are one shorter (2.65 Å) and two longer (2.66 Å) Fe–Ga bond lengths. In the second Fe site, Fe is bonded to three equivalent Ho, seven Fe, and two equivalent Ga atoms to form FeHo3Ga2Fe7 cuboctahedra that share corners with four equivalent FeHo3Ga2Fe7 cuboctahedra, corners with five GaHo2Fe10 cuboctahedra, corners with four equivalent CHo2Fe4 octahedra, an edgeedge with one FeHo3Ga2Fe7 cuboctahedra, edges with three GaHo2Fe10 cuboctahedra, a faceface with one FeHo3Ga2Fe7 cuboctahedra, faces with three GaHo2Fe10 cuboctahedra, and faces with two equivalent CHo2Fe4 octahedra. The corner-sharing octahedra tilt angles range from 63–69°. There are a spread of Fe–Fe bond distances ranging from 2.50–2.60 Å. Both Fe–Ga bond lengths are 2.48 Å. In the third Fe site, Fe is bonded in a single-bond geometry to three Fe, two Ga, and one C atom. The Fe–Fe bond length is 2.61 Å. There are one shorter (2.49 Å) and one longer (2.50 Å) Fe–Ga bond lengths. The Fe–C bond length is 1.91 Å. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Ho, eight Fe, and two equivalent Ga atoms. Both Fe–Fe bond lengths are 2.51 Å. Both Fe–Ga bond lengths are 2.46 Å. In the fifth Fe site, Fe is bonded in a single-bond geometry to four Fe, two Ga, and one C atom. There are one shorter (2.44 Å) and one longer (2.45 Å) Fe–Ga bond lengths. The Fe–C bond length is 1.84 Å. There are two inequivalent Ga sites. In the first Ga site, Ga is bonded to two equivalent Ho and ten Fe atoms to form distorted GaHo2Fe10 cuboctahedra that share corners with four equivalent GaHo2Fe10 cuboctahedra, corners with six equivalent FeHo3Ga2Fe7 cuboctahedra, edges with two equivalent FeHo3Ga2Fe7 cuboctahedra, faces with two equivalent FeHo3Ga2Fe7 cuboctahedra, faces with four equivalent GaHo2Fe10 cuboctahedra, and faces with four equivalent CHo2Fe4 octahedra. In the second Ga site, Ga is bonded to two equivalent Ho and ten Fe atoms to form distorted GaHo2Fe10 cuboctahedra that share corners with two equivalent FeHo3Ga2Fe7 cuboctahedra, corners with four GaHo2Fe10 cuboctahedra, corners with two equivalent CHo2Fe4 octahedra, edges with two equivalent FeHo3Ga2Fe7 cuboctahedra, faces with two equivalent FeHo3Ga2Fe7 cuboctahedra, faces with four GaHo2Fe10 cuboctahedra, and faces with two equivalent CHo2Fe4 octahedra. The corner-sharing octahedral tilt angles are 46°. C is bonded to two equivalent Ho and four Fe atoms to form CHo2Fe4 octahedra that share corners with two equivalent GaHo2Fe10 cuboctahedra, corners with four equivalent FeHo3Ga2Fe7 cuboctahedra, corners with two equivalent CHo2Fe4 octahedra, faces with two equivalent FeHo3Ga2Fe7 cuboctahedra, and faces with four GaHo2Fe10 cuboctahedra. The corner-sharing octahedral tilt angles are 63°.

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2020-06-04. Materials Data on Ho2Ga3(Fe7C)2 by Materials Project. https://doi.org/10.17188/1651527

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