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DOE OSTI · 1664887

Materials Data on Er4Fe29Si5 by Materials Project

Abstract

Er4Fe29Si5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Er sites. In the first Er site, Er is bonded in a 6-coordinate geometry to seventeen Fe and two Si atoms. There are a spread of Er–Fe bond distances ranging from 2.87–3.26 Å. There are one shorter (3.05 Å) and one longer (3.30 Å) Er–Si bond lengths. In the second Er site, Er is bonded in a 10-coordinate geometry to eighteen Fe and one Si atom. There are a spread of Er–Fe bond distances ranging from 2.88–3.29 Å. The Er–Si bond length is 3.04 Å. There are sixteen inequivalent Fe sites. In the first Fe site, Fe is bonded to three Er, seven Fe, and two Si atoms to form distorted FeEr3Fe7Si2 cuboctahedra that share corners with sixteen FeEr2Fe8Si2 cuboctahedra, edges with seven FeEr3Fe8Si cuboctahedra, and faces with twelve FeEr3Fe7Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.39–2.55 Å. There are one shorter (2.36 Å) and one longer (2.59 Å) Fe–Si bond lengths. In the second Fe site, Fe is bonded to three Er, eight Fe, and one Si atom to form FeEr3Fe8Si cuboctahedra that share corners with sixteen FeEr3Fe7Si2 cuboctahedra, edges with nine FeEr2Fe8Si2 cuboctahedra, and faces with ten FeEr2Fe8Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.39–2.56 Å. The Fe–Si bond length is 2.54 Å. In the third Fe site, Fe is bonded to three Er, eight Fe, and one Si atom to form FeEr3Fe8Si cuboctahedra that share corners with sixteen FeEr2Fe8Si2 cuboctahedra, edges with eight FeEr3Fe7Si2 cuboctahedra, and faces with eleven FeEr3Fe7Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.38–2.56 Å. The Fe–Si bond length is 2.54 Å. In the fourth Fe site, Fe is bonded to three Er, seven Fe, and two Si atoms to form distorted FeEr3Fe7Si2 cuboctahedra that share corners with sixteen FeEr3Fe7Si2 cuboctahedra, edges with eight FeEr2Fe8Si2 cuboctahedra, and faces with eleven FeEr3Fe7Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.39–2.56 Å. There are one shorter (2.36 Å) and one longer (2.58 Å) Fe–Si bond lengths. In the fifth Fe site, Fe is bonded to three Er, eight Fe, and one Si atom to form FeEr3Fe8Si cuboctahedra that share corners with fourteen FeEr2Fe8Si2 cuboctahedra, edges with eight FeEr2Fe8Si2 cuboctahedra, and faces with eleven FeEr3Fe7Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.39–2.58 Å. The Fe–Si bond length is 2.56 Å. In the sixth Fe site, Fe is bonded to three Er, eight Fe, and one Si atom to form distorted FeEr3Fe8Si cuboctahedra that share corners with fifteen FeEr2Fe8Si2 cuboctahedra, edges with seven FeEr3Fe7Si2 cuboctahedra, and faces with twelve FeEr3Fe7Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.40–2.58 Å. The Fe–Si bond length is 2.48 Å. In the seventh Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Er, seven Fe, and three Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.44–2.52 Å. There are a spread of Fe–Si bond distances ranging from 2.42–2.95 Å. In the eighth Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent Er, eight Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.43–2.51 Å. There are one shorter (2.81 Å) and one longer (2.82 Å) Fe–Si bond lengths. In the ninth Fe site, Fe is bonded in a 12-coordinate geometry to two Er, eight Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.42–2.51 Å. There are one shorter (2.81 Å) and one longer (2.82 Å) Fe–Si bond lengths. In the tenth Fe site, Fe is bonded in a 12-coordinate geometry to two Er, seven Fe, and three Si atoms. There are one shorter (2.44 Å) and one longer (2.52 Å) Fe–Fe bond lengths. There are a spread of Fe–Si bond distances ranging from 2.41–2.95 Å. In the eleventh Fe site, Fe is bonded to two Er, eight Fe, and two equivalent Si atoms to form distorted FeEr2Fe8Si2 cuboctahedra that share corners with twelve FeEr2Fe8Si2 cuboctahedra, edges with five FeEr3Fe8Si cuboctahedra, and faces with twelve FeEr3Fe7Si2 cuboctahedra. There are one shorter (2.42 Å) and one longer (2.43 Å) Fe–Fe bond lengths. Both Fe–Si bond lengths are 2.74 Å. In the twelfth Fe site, Fe is bonded in a 12-coordinate geometry to two Er, eight Fe, and two equivalent Si atoms. There are one shorter (2.42 Å) and one longer (2.43 Å) Fe–Fe bond lengths. There are one shorter (2.77 Å) and one longer (2.78 Å) Fe–Si bond lengths. In the thirteenth Fe site, Fe is bonded to two Er, eight Fe, and two Si atoms to form distorted FeEr2Fe8Si2 cuboctahedra that share corners with fourteen FeEr2Fe8Si2 cuboctahedra, edges with seven FeEr3Fe7Si2 cuboctahedra, and faces with ten FeEr2Fe8Si2 cuboctahedra. There are one shorter (2.47 Å) and one longer (2.53 Å) Fe–Si bond lengths. In the fourteenth Fe site, Fe is bonded to two equivalent Er, eight Fe, and two equivalent Si atoms to form distorted FeEr2Fe8Si2 cuboctahedra that share corners with fourteen FeEr3Fe8Si cuboctahedra, edges with six FeEr3Fe7Si2 cuboctahedra, and faces with ten FeEr3Fe7Si2 cuboctahedra. Both Fe–Si bond lengths are 2.47 Å. In the fifteenth Fe site, Fe is bonded to two equivalent Er, eight Fe, and two equivalent Si atoms to form distorted FeEr2Fe8Si2 cuboctahedra that share corners with fourteen FeEr2Fe8Si2 cuboctahedra, edges with eight FeEr3Fe8Si cuboctahedra, and faces with ten FeEr2Fe8Si2 cuboctahedra. Both Fe–Si bond lengths are 2.52 Å. In the sixteenth Fe site, Fe is bonded to two equivalent Er, eight Fe, and two equivalent Si atoms to form distorted FeEr2Fe8Si2 cuboctahedra that share corners with sixteen FeEr3Fe7Si2 cuboctahedra, edges with six FeEr3Fe8Si cuboctahedra, and faces with ten FeEr3Fe8Si cuboctahedra. Both Fe–Si bond lengths are 2.54 Å. There are three inequivalent Si sites. In the first Si site, Si is bonded in a 12-coordinate geometry to two equivalent Er, eight Fe, and two equivalent Si atoms. Both Si–Si bond lengths are 2.68 Å. In the second Si site, Si is bonded in a 12-coordinate geometry to one Er, eleven Fe, and two Si atoms. The Si–Si bond length is 2.48 Å. In the third Si site, Si is bonded in a 8-coordinate geometry to one Er, twelve Fe, and one Si atom. The Si–Si bond length is 2.51 Å.

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2020-06-05. Materials Data on Er4Fe29Si5 by Materials Project. https://doi.org/10.17188/1664887

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