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DOE OSTI · 1276891

Materials Data on Sm4Al23Ni6 by Materials Project

Abstract

Sm4Ni6Al23 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Sm sites. In the first Sm site, Sm is bonded in a 11-coordinate geometry to two equivalent Ni and thirteen Al atoms. Both Sm–Ni bond lengths are 3.28 Å. There are a spread of Sm–Al bond distances ranging from 3.07–3.39 Å. In the second Sm site, Sm is bonded in a 11-coordinate geometry to two equivalent Ni and thirteen Al atoms. Both Sm–Ni bond lengths are 3.27 Å. There are a spread of Sm–Al bond distances ranging from 3.08–3.34 Å. There are three inequivalent Ni sites. In the first Ni site, Ni is bonded in a 7-coordinate geometry to two equivalent Sm and seven Al atoms. There are a spread of Ni–Al bond distances ranging from 2.34–2.53 Å. In the second 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 2.41–2.76 Å. In the third Ni site, Ni is bonded in a 8-coordinate geometry to two equivalent Sm and eight Al atoms. There are a spread of Ni–Al bond distances ranging from 2.38–2.55 Å. There are twelve inequivalent Al sites. In the first Al site, Al is bonded to two Sm, two equivalent Ni, and eight Al atoms to form distorted face-sharing AlSm2Al8Ni2 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.72–3.00 Å. In the second Al site, Al is bonded in a 12-coordinate geometry to four Sm and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.89–3.18 Å. In the third Al site, Al is bonded in a 3-coordinate geometry to two equivalent Sm, three Ni, and one Al atom. In the fourth Al site, Al is bonded in a 3-coordinate geometry to one Sm, three equivalent Ni, and six Al atoms. There are a spread of Al–Al bond distances ranging from 2.62–2.77 Å. In the fifth Al site, Al is bonded in a distorted single-bond geometry to three Sm, one Ni, and four Al atoms. Both Al–Al bond lengths are 2.91 Å. In the sixth Al site, Al is bonded in a distorted trigonal non-coplanar geometry to one Sm, three Ni, and one Al atom. In the seventh Al site, Al is bonded in a 3-coordinate geometry to three equivalent Sm and three equivalent Ni atoms. In the eighth Al site, Al is bonded in a distorted bent 150 degrees geometry to three Sm, two Ni, and three Al atoms. In the ninth Al site, Al is bonded in a 2-coordinate geometry to three Sm, two equivalent Ni, and one Al atom. In the tenth Al site, Al is bonded in a distorted bent 150 degrees geometry to two equivalent Sm, two Ni, and five Al atoms. In the eleventh Al site, Al is bonded in a distorted trigonal planar geometry to three Ni and two Al atoms. In the twelfth Al site, Al is bonded in a 12-coordinate geometry to four equivalent Sm and six Al atoms.

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2020-07-20. Materials Data on Sm4Al23Ni6 by Materials Project. https://doi.org/10.17188/1276891

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