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DOE OSTI · 1679925

Materials Data on Ho4Fe29Si5 by Materials Project

Abstract

Ho4Fe29Si5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Ho sites. In the first Ho site, Ho is bonded in a 6-coordinate geometry to seventeen Fe and two Si atoms. There are a spread of Ho–Fe bond distances ranging from 2.87–3.26 Å. There are one shorter (3.06 Å) and one longer (3.32 Å) Ho–Si bond lengths. In the second Ho site, Ho is bonded in a 10-coordinate geometry to eighteen Fe and one Si atom. There are a spread of Ho–Fe bond distances ranging from 2.89–3.30 Å. The Ho–Si bond length is 3.04 Å. There are sixteen inequivalent Fe sites. In the first Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Ho, eight Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.42–2.58 Å. There are one shorter (2.81 Å) and one longer (2.82 Å) Fe–Si bond lengths. In the second Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Ho, seven Fe, and three Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.45–2.56 Å. There are a spread of Fe–Si bond distances ranging from 2.42–2.97 Å. In the third Fe site, Fe is bonded in a 12-coordinate geometry to two Ho, eight Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.43–2.58 Å. There are one shorter (2.81 Å) and one longer (2.83 Å) Fe–Si bond lengths. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to two Ho, seven Fe, and three Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.45–2.56 Å. There are a spread of Fe–Si bond distances ranging from 2.41–2.97 Å. In the fifth Fe site, Fe is bonded to two Ho, eight Fe, and two equivalent Si atoms to form distorted FeHo2Fe8Si2 cuboctahedra that share corners with twelve FeHo2Fe8Si2 cuboctahedra, edges with five FeHo2Fe8Si2 cuboctahedra, and faces with twelve FeHo3Fe7Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.42–2.60 Å. There are one shorter (2.71 Å) and one longer (2.72 Å) Fe–Si bond lengths. In the sixth Fe site, Fe is bonded in a 12-coordinate geometry to two Ho, eight Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.43–2.58 Å. Both Fe–Si bond lengths are 2.77 Å. In the seventh Fe site, Fe is bonded to three Ho, seven Fe, and two Si atoms to form distorted FeHo3Fe7Si2 cuboctahedra that share corners with sixteen FeHo2Fe8Si2 cuboctahedra, edges with seven FeHo3Fe8Si cuboctahedra, and faces with twelve FeHo2Fe8Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.39–2.48 Å. There are one shorter (2.36 Å) and one longer (2.59 Å) Fe–Si bond lengths. In the eighth Fe site, Fe is bonded to three Ho, eight Fe, and one Si atom to form a mixture of face, edge, and corner-sharing FeHo3Fe8Si cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.39–2.44 Å. The Fe–Si bond length is 2.54 Å. In the ninth Fe site, Fe is bonded to three Ho, eight Fe, and one Si atom to form a mixture of face, edge, and corner-sharing FeHo3Fe8Si cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.38–2.41 Å. The Fe–Si bond length is 2.54 Å. In the tenth Fe site, Fe is bonded to three Ho, seven Fe, and two Si atoms to form a mixture of distorted face, edge, and corner-sharing FeHo3Fe7Si2 cuboctahedra. There are one shorter (2.40 Å) and one longer (2.44 Å) Fe–Fe bond lengths. There are one shorter (2.36 Å) and one longer (2.58 Å) Fe–Si bond lengths. In the eleventh Fe site, Fe is bonded to three Ho, eight Fe, and one Si atom to form a mixture of face, edge, and corner-sharing FeHo3Fe8Si cuboctahedra. Both Fe–Fe bond lengths are 2.39 Å. The Fe–Si bond length is 2.57 Å. In the twelfth Fe site, Fe is bonded to three Ho, eight Fe, and one Si atom to form distorted FeHo3Fe8Si cuboctahedra that share corners with fifteen FeHo2Fe8Si2 cuboctahedra, edges with seven FeHo3Fe7Si2 cuboctahedra, and faces with twelve FeHo2Fe8Si2 cuboctahedra. Both Fe–Fe bond lengths are 2.41 Å. The Fe–Si bond length is 2.48 Å. In the thirteenth Fe site, Fe is bonded to two Ho, eight Fe, and two Si atoms to form a mixture of distorted face, edge, and corner-sharing FeHo2Fe8Si2 cuboctahedra. There are one shorter (2.46 Å) and one longer (2.53 Å) Fe–Si bond lengths. In the fourteenth Fe site, Fe is bonded to two equivalent Ho, eight Fe, and two equivalent Si atoms to form distorted FeHo2Fe8Si2 cuboctahedra that share corners with fourteen FeHo2Fe8Si2 cuboctahedra, edges with six FeHo3Fe7Si2 cuboctahedra, and faces with ten FeHo2Fe8Si2 cuboctahedra. Both Fe–Si bond lengths are 2.46 Å. In the fifteenth Fe site, Fe is bonded to two equivalent Ho, eight Fe, and two equivalent Si atoms to form a mixture of distorted face, edge, and corner-sharing FeHo2Fe8Si2 cuboctahedra. Both Fe–Si bond lengths are 2.52 Å. In the sixteenth Fe site, Fe is bonded to two equivalent Ho, eight Fe, and two equivalent Si atoms to form distorted FeHo2Fe8Si2 cuboctahedra that share corners with sixteen FeHo2Fe8Si2 cuboctahedra, edges with six FeHo3Fe8Si cuboctahedra, and faces with ten FeHo3Fe8Si cuboctahedra. Both Fe–Si bond lengths are 2.55 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded in a 12-coordinate geometry to two equivalent Ho, eight Fe, and two equivalent Si atoms. Both Si–Si bond lengths are 2.70 Å. In the second Si site, Si is bonded in a 12-coordinate geometry to one Ho, eleven Fe, and two Si atoms. The Si–Si bond length is 2.49 Å. In the third Si site, Si is bonded in a 8-coordinate geometry to one Ho, twelve Fe, and one Si atom. The Si–Si bond length is 2.52 Å.

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2020-06-04. Materials Data on Ho4Fe29Si5 by Materials Project. https://doi.org/10.17188/1679925

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