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DOE OSTI · 1741733

Materials Data on U2(CuNi)5 by Materials Project

Abstract

U2(NiCu)5 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are two inequivalent U sites. In the first U site, U is bonded in a 1-coordinate geometry to ten Ni and six Cu atoms. There are a spread of U–Ni bond distances ranging from 2.79–3.02 Å. There are four shorter (2.83 Å) and two longer (2.86 Å) U–Cu bond lengths. In the second U site, U is bonded in a 4-coordinate geometry to seven Ni and nine Cu atoms. There are a spread of U–Ni bond distances ranging from 2.80–3.02 Å. There are a spread of U–Cu bond distances ranging from 2.81–2.85 Å. There are five inequivalent Ni sites. In the first Ni site, Ni is bonded to three equivalent U, five Ni, and four Cu atoms to form distorted NiU3Cu4Ni5 cuboctahedra that share corners with four NiU3Cu5Ni4 cuboctahedra, corners with fourteen CuU3Cu3Ni6 cuboctahedra, edges with six equivalent NiU3Cu4Ni5 cuboctahedra, faces with six NiU3Cu5Ni4 cuboctahedra, and faces with twelve CuU3Cu3Ni6 cuboctahedra. There are a spread of Ni–Ni bond distances ranging from 2.44–2.85 Å. There are two shorter (2.39 Å) and two longer (2.41 Å) Ni–Cu bond lengths. In the second Ni site, Ni is bonded to three U, four Ni, and five Cu atoms to form distorted NiU3Cu5Ni4 cuboctahedra that share corners with eight NiU3Cu4Ni5 cuboctahedra, corners with ten CuU3Cu3Ni6 cuboctahedra, edges with six NiU3Cu5Ni4 cuboctahedra, faces with three equivalent NiU3Cu4Ni5 cuboctahedra, and faces with fifteen CuU3Cu3Ni6 cuboctahedra. There are two shorter (2.81 Å) and one longer (2.84 Å) Ni–Ni bond lengths. There are a spread of Ni–Cu bond distances ranging from 2.41–2.43 Å. In the third Ni site, Ni is bonded to three U, four Ni, and five Cu atoms to form distorted NiU3Cu5Ni4 cuboctahedra that share corners with eight NiU3Cu4Ni5 cuboctahedra, corners with ten CuU3Cu3Ni6 cuboctahedra, edges with six NiU3Cu5Ni4 cuboctahedra, faces with three equivalent NiU3Cu4Ni5 cuboctahedra, and faces with fifteen CuU3Cu3Ni6 cuboctahedra. There are two shorter (2.80 Å) and one longer (2.81 Å) Ni–Ni bond lengths. There are a spread of Ni–Cu bond distances ranging from 2.40–2.45 Å. In the fourth Ni site, Ni is bonded in a 4-coordinate geometry to four U, three Ni, and nine Cu atoms. There are a spread of Ni–Cu bond distances ranging from 2.81–2.86 Å. In the fifth Ni site, Ni is bonded in a 4-coordinate geometry to four U, six Ni, and six Cu atoms. There are a spread of Ni–Cu bond distances ranging from 2.80–2.85 Å. There are three inequivalent Cu sites. In the first Cu site, Cu is bonded to three U, six Ni, and three Cu atoms to form distorted CuU3Cu3Ni6 cuboctahedra that share corners with six NiU3Cu4Ni5 cuboctahedra, corners with twelve CuU3Cu3Ni6 cuboctahedra, edges with six CuU3Cu3Ni6 cuboctahedra, faces with nine NiU3Cu4Ni5 cuboctahedra, and faces with nine CuU3Cu3Ni6 cuboctahedra. There are a spread of Cu–Cu bond distances ranging from 2.37–2.40 Å. In the second Cu site, Cu is bonded to three U, six Ni, and three Cu atoms to form distorted CuU3Cu3Ni6 cuboctahedra that share corners with six NiU3Cu4Ni5 cuboctahedra, corners with twelve CuU3Cu3Ni6 cuboctahedra, edges with six CuU3Cu3Ni6 cuboctahedra, faces with nine NiU3Cu4Ni5 cuboctahedra, and faces with nine CuU3Cu3Ni6 cuboctahedra. There are a spread of Cu–Cu bond distances ranging from 2.36–2.43 Å. In the third Cu site, Cu is bonded to three equivalent U, five Ni, and four Cu atoms to form CuU3Cu4Ni5 cuboctahedra that share corners with eight CuU3Cu3Ni6 cuboctahedra, corners with ten NiU3Cu4Ni5 cuboctahedra, edges with six equivalent CuU3Cu4Ni5 cuboctahedra, faces with six NiU3Cu5Ni4 cuboctahedra, and faces with twelve CuU3Cu3Ni6 cuboctahedra.

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2020-05-03. Materials Data on U2(CuNi)5 by Materials Project. https://doi.org/10.17188/1741733

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