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DOE OSTI · 1681737

Materials Data on U(Fe5Si)2 by Materials Project

Abstract

UFe10Si2 crystallizes in the orthorhombic Fmmm space group. The structure is three-dimensional. U is bonded in a 12-coordinate geometry to sixteen Fe and four equivalent Si atoms. There are a spread of U–Fe bond distances ranging from 2.92–3.14 Å. All U–Si bond lengths are 3.14 Å. There are three inequivalent Fe sites. In the first Fe site, Fe is bonded in a 10-coordinate geometry to one U, eleven Fe, and two equivalent Si atoms. There are a spread of Fe–Fe bond distances ranging from 2.37–2.93 Å. Both Fe–Si bond lengths are 2.51 Å. In the second Fe site, Fe is bonded to two equivalent U and ten Fe atoms to form FeU2Fe10 cuboctahedra that share corners with four equivalent SiU2Fe8Si2 cuboctahedra, corners with six equivalent FeU2Fe10 cuboctahedra, edges with four equivalent SiU2Fe8Si2 cuboctahedra, faces with two equivalent FeU2Fe10 cuboctahedra, and faces with four equivalent SiU2Fe8Si2 cuboctahedra. There are two shorter (2.38 Å) and four longer (2.41 Å) Fe–Fe bond lengths. In the third Fe site, Fe is bonded in a 12-coordinate geometry to two equivalent U, eight Fe, and two equivalent Si atoms. There are one shorter (2.52 Å) and one longer (2.58 Å) Fe–Fe bond lengths. Both Fe–Si bond lengths are 2.37 Å. Si is bonded to two equivalent U, eight Fe, and two equivalent Si atoms to form distorted SiU2Fe8Si2 cuboctahedra that share corners with four equivalent FeU2Fe10 cuboctahedra, corners with six equivalent SiU2Fe8Si2 cuboctahedra, edges with four equivalent FeU2Fe10 cuboctahedra, faces with two equivalent SiU2Fe8Si2 cuboctahedra, and faces with four equivalent FeU2Fe10 cuboctahedra. Both Si–Si bond lengths are 2.38 Å.

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2020-06-05. Materials Data on U(Fe5Si)2 by Materials Project. https://doi.org/10.17188/1681737

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