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DOE OSTI · 1727827

Materials Data on U2Co15Ge2 by Materials Project

Abstract

U2Co15Ge2 crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. there are two inequivalent U sites. In the first U site, U is bonded in a 6-coordinate geometry to eighteen Co atoms. There are a spread of U–Co bond distances ranging from 2.81–3.19 Å. In the second U site, U is bonded to eighteen Co and two equivalent Ge atoms to form distorted UCo18Ge2 hexagonal bipyramids that share corners with six equivalent UCo18Ge2 hexagonal bipyramids and faces with twenty-four CoU2Co8Ge2 cuboctahedra. There are a spread of U–Co bond distances ranging from 2.83–3.16 Å. Both U–Ge bond lengths are 2.91 Å. There are seven inequivalent Co sites. In the first Co site, Co is bonded to two equivalent U, eight Co, and two equivalent Ge atoms to form distorted CoU2Co8Ge2 cuboctahedra that share corners with fourteen CoU2Co8Ge2 cuboctahedra, edges with six CoU3Co8Ge cuboctahedra, faces with ten CoU2Co8Ge2 cuboctahedra, and faces with two equivalent UCo18Ge2 hexagonal bipyramids. There are a spread of Co–Co bond distances ranging from 2.41–2.46 Å. Both Co–Ge bond lengths are 2.52 Å. In the second Co site, Co is bonded to two equivalent U, eight Co, and two equivalent Ge atoms to form distorted CoU2Co8Ge2 cuboctahedra that share corners with fourteen CoU2Co8Ge2 cuboctahedra, edges with six CoU3Co8Ge cuboctahedra, faces with ten CoU2Co8Ge2 cuboctahedra, and faces with two equivalent UCo18Ge2 hexagonal bipyramids. There are four shorter (2.41 Å) and four longer (2.45 Å) Co–Co bond lengths. Both Co–Ge bond lengths are 2.53 Å. In the third Co site, Co is bonded in a 12-coordinate geometry to two U, eight Co, and two equivalent Ge atoms. There are a spread of Co–Co bond distances ranging from 2.50–2.61 Å. Both Co–Ge bond lengths are 2.86 Å. In the fourth Co site, Co is bonded in a 12-coordinate geometry to two U, eight Co, and two equivalent Ge atoms. There are a spread of Co–Co bond distances ranging from 2.50–2.60 Å. Both Co–Ge bond lengths are 2.86 Å. In the fifth Co site, Co is bonded in a 12-coordinate geometry to two U, eight Co, and two equivalent Ge atoms. There are two shorter (2.50 Å) and two longer (2.53 Å) Co–Co bond lengths. Both Co–Ge bond lengths are 2.85 Å. In the sixth Co site, Co is bonded to three U, eight Co, and one Ge atom to form distorted CoU3Co8Ge cuboctahedra that share corners with fifteen CoU2Co8Ge2 cuboctahedra, edges with eight CoU2Co8Ge2 cuboctahedra, faces with ten CoU2Co8Ge2 cuboctahedra, and faces with three equivalent UCo18Ge2 hexagonal bipyramids. Both Co–Co bond lengths are 2.33 Å. The Co–Ge bond length is 2.61 Å. In the seventh Co site, Co is bonded to three U, eight Co, and one Ge atom to form distorted CoU3Co8Ge cuboctahedra that share corners with fifteen CoU2Co8Ge2 cuboctahedra, edges with eight CoU2Co8Ge2 cuboctahedra, faces with ten CoU2Co8Ge2 cuboctahedra, and faces with three equivalent UCo18Ge2 hexagonal bipyramids. The Co–Ge bond length is 2.61 Å. Ge is bonded in a 8-coordinate geometry to one U, twelve Co, and one Ge atom. The Ge–Ge bond length is 2.48 Å.

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2020-06-05. Materials Data on U2Co15Ge2 by Materials Project. https://doi.org/10.17188/1727827

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