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DOE OSTI · 1753199

Materials Data on UFe5Co5Si2 by Materials Project

Abstract

UFe5Co5Si2 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. U is bonded in a 4-coordinate geometry to ten Fe, six Co, and four equivalent Si atoms. There are a spread of U–Fe bond distances ranging from 3.00–3.12 Å. There are a spread of U–Co bond distances ranging from 2.77–3.04 Å. There are two shorter (3.10 Å) and two longer (3.11 Å) U–Si bond lengths. There are four inequivalent Fe sites. In the first Fe site, Fe is bonded to two equivalent U, five Fe, and five Co atoms to form distorted FeU2Fe5Co5 cuboctahedra that share corners with four equivalent SiU2Fe3Co5Si2 cuboctahedra, corners with eight FeU2Fe5Co5 cuboctahedra, an edgeedge with one FeU2Fe3Co5Si2 cuboctahedra, edges with four equivalent SiU2Fe3Co5Si2 cuboctahedra, faces with four FeU2Fe5Co5 cuboctahedra, and faces with four equivalent SiU2Fe3Co5Si2 cuboctahedra. There are a spread of Fe–Fe bond distances ranging from 2.36–2.42 Å. There are a spread of Fe–Co bond distances ranging from 2.35–2.52 Å. In the second Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent U, three Fe, five Co, and two equivalent Si atoms. The Fe–Fe bond length is 2.54 Å. There are a spread of Fe–Co bond distances ranging from 2.54–2.61 Å. Both Fe–Si bond lengths are 2.37 Å. In the third Fe site, Fe is bonded to two equivalent U, three Fe, five Co, and two equivalent Si atoms to form distorted FeU2Fe3Co5Si2 cuboctahedra that share corners with four equivalent FeU2Fe5Co5 cuboctahedra, corners with four equivalent SiU2Fe3Co5Si2 cuboctahedra, edges with two equivalent SiU2Fe3Co5Si2 cuboctahedra, edges with four FeU2Fe5Co5 cuboctahedra, faces with four equivalent FeU2Fe5Co5 cuboctahedra, and faces with four equivalent SiU2Fe3Co5Si2 cuboctahedra. The Fe–Fe bond length is 2.54 Å. There are a spread of Fe–Co bond distances ranging from 2.55–2.61 Å. Both Fe–Si bond lengths are 2.38 Å. In the fourth Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent U, four Fe, four Co, and two equivalent Si atoms. There are a spread of Fe–Co bond distances ranging from 2.53–2.61 Å. Both Fe–Si bond lengths are 2.37 Å. There are five inequivalent Co sites. In the first Co site, Co is bonded in a 10-coordinate geometry to one U, five Fe, two Co, and two equivalent Si atoms. There are one shorter (2.51 Å) and one longer (2.58 Å) Co–Co bond lengths. Both Co–Si bond lengths are 2.46 Å. In the second Co site, Co is bonded in a 10-coordinate geometry to one U, five Fe, two Co, and two equivalent Si atoms. The Co–Co bond length is 2.53 Å. Both Co–Si bond lengths are 2.47 Å. In the third Co site, Co is bonded in a 10-coordinate geometry to one U, four Fe, three Co, and two equivalent Si atoms. There are one shorter (2.50 Å) and two longer (2.60 Å) Co–Co bond lengths. Both Co–Si bond lengths are 2.44 Å. In the fourth Co site, Co is bonded in a 10-coordinate geometry to one U, six Fe, one Co, and two equivalent Si atoms. Both Co–Si bond lengths are 2.46 Å. In the fifth Co site, Co is bonded in a 12-coordinate geometry to two equivalent U, four Fe, four Co, and two equivalent Si atoms. Both Co–Si bond lengths are 2.32 Å. Si is bonded to two equivalent U, three Fe, five Co, and two equivalent Si atoms to form distorted SiU2Fe3Co5Si2 cuboctahedra that share corners with six FeU2Fe5Co5 cuboctahedra, corners with six equivalent SiU2Fe3Co5Si2 cuboctahedra, edges with five FeU2Fe5Co5 cuboctahedra, faces with two equivalent SiU2Fe3Co5Si2 cuboctahedra, and faces with six FeU2Fe5Co5 cuboctahedra. There are one shorter (2.41 Å) and one longer (2.42 Å) Si–Si bond lengths.

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2020-06-04. Materials Data on UFe5Co5Si2 by Materials Project. https://doi.org/10.17188/1753199

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