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DOE OSTI · 1276858

Materials Data on U4Al18Ni5 by Materials Project

Abstract

U4Ni5Al18 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. there are four inequivalent U sites. In the first U site, U is bonded in a 12-coordinate geometry to two equivalent Ni and thirteen Al atoms. Both U–Ni bond lengths are 3.20 Å. There are a spread of U–Al bond distances ranging from 2.99–3.44 Å. In the second U site, U is bonded in a 12-coordinate geometry to two equivalent Ni and thirteen Al atoms. Both U–Ni bond lengths are 3.20 Å. There are a spread of U–Al bond distances ranging from 2.99–3.35 Å. In the third U site, U is bonded in a 12-coordinate geometry to two equivalent Ni and thirteen Al atoms. Both U–Ni bond lengths are 3.21 Å. There are a spread of U–Al bond distances ranging from 3.00–3.55 Å. In the fourth U site, U is bonded in a 7-coordinate geometry to two equivalent Ni and thirteen Al atoms. Both U–Ni bond lengths are 3.22 Å. There are a spread of U–Al bond distances ranging from 2.97–3.37 Å. There are five inequivalent Ni sites. In the first Ni site, Ni is bonded in a 7-coordinate geometry to two equivalent U and seven Al atoms. There are a spread of Ni–Al bond distances ranging from 2.37–2.62 Å. In the second Ni site, Ni is bonded in a 7-coordinate geometry to two equivalent U and seven Al atoms. There are a spread of Ni–Al bond distances ranging from 2.33–2.49 Å. In the third Ni site, Ni is bonded in a 7-coordinate geometry to two equivalent U and seven Al atoms. There are a spread of Ni–Al bond distances ranging from 2.34–2.50 Å. In the fourth Ni site, Ni is bonded in a 9-coordinate geometry to nine Al atoms. There are a spread of Ni–Al bond distances ranging from 2.39–2.73 Å. In the fifth Ni site, Ni is bonded in a 7-coordinate geometry to two equivalent U and seven Al atoms. There are a spread of Ni–Al bond distances ranging from 2.36–2.58 Å. There are eighteen inequivalent Al sites. In the first Al site, Al is bonded in a distorted single-bond geometry to three U, one Ni, and four Al atoms. There are two shorter (2.84 Å) and two longer (2.87 Å) Al–Al bond lengths. In the second Al site, Al is bonded in a 12-coordinate geometry to four U and seven Al atoms. There are a spread of Al–Al bond distances ranging from 2.85–3.07 Å. In the third Al site, Al is bonded in a 12-coordinate geometry to four U and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.78–3.19 Å. In the fourth Al site, Al is bonded in a 2-coordinate geometry to two U, two Ni, and two equivalent Al atoms. In the fifth Al site, Al is bonded to two U, two equivalent Ni, and eight Al atoms to form distorted face-sharing AlU2Al8Ni2 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.71–2.82 Å. In the sixth Al site, Al is bonded in a 2-coordinate geometry to three U, two equivalent Ni, and one Al atom. In the seventh Al site, Al is bonded in a 5-coordinate geometry to two U and five Ni atoms. In the eighth Al site, Al is bonded in a 3-coordinate geometry to three U, three Ni, and one Al atom. In the ninth Al site, Al is bonded in a 3-coordinate geometry to three U, three Ni, and one Al atom. The Al–Al bond length is 2.98 Å. In the tenth Al site, Al is bonded in a 3-coordinate geometry to two equivalent U, three Ni, and one Al atom. In the eleventh Al site, Al is bonded in a distorted water-like geometry to three U, two equivalent Ni, and one Al atom. In the twelfth Al site, Al is bonded in a distorted bent 150 degrees geometry to three U, two Ni, and three Al atoms. In the thirteenth Al site, Al is bonded in a distorted trigonal non-coplanar geometry to three U, three Ni, and one Al atom. In the fourteenth Al site, Al is bonded in a 12-coordinate geometry to four U and seven Al atoms. There are two shorter (2.86 Å) and one longer (3.02 Å) Al–Al bond lengths. In the fifteenth Al site, Al is bonded in a distorted single-bond geometry to three U, one Ni, and four Al atoms. In the sixteenth Al site, Al is bonded in a 3-coordinate geometry to two equivalent U, three Ni, and one Al atom. In the seventeenth Al site, Al is bonded in a distorted bent 150 degrees geometry to three U, two Ni, and three Al atoms. In the eighteenth Al site, Al is bonded in a 3-coordinate geometry to three U, three Ni, and one Al atom.

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2020-06-24. Materials Data on U4Al18Ni5 by Materials Project. https://doi.org/10.17188/1276858

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