DOI: 10.17188/1675994
title: Materials Data on Y3(Al7Cr2)4 by Materials Project

description: Y3(Cr2Al7)4 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are two inequivalent Y sites. In the first Y site, Y is bonded in a 12-coordinate geometry to six Cr and fourteen Al atoms. There are two shorter (3.44 Å) and four longer (3.45 Å) Y–Cr bond lengths. There are a spread of Y–Al bond distances ranging from 3.07–3.41 Å. In the second Y site, Y is bonded in a 12-coordinate geometry to five Cr and fifteen Al atoms. There are a spread of Y–Cr bond distances ranging from 3.41–3.49 Å. There are a spread of Y–Al bond distances ranging from 3.08–3.43 Å. There are three inequivalent Cr sites. In the first Cr site, Cr is bonded in a 12-coordinate geometry to two equivalent Y, two equivalent Cr, and eight Al atoms. Both Cr–Cr bond lengths are 2.57 Å. There are a spread of Cr–Al bond distances ranging from 2.52–2.66 Å. In the second Cr site, Cr is bonded in a 12-coordinate geometry to two equivalent Y, two equivalent Cr, and eight Al atoms. Both Cr–Cr bond lengths are 2.57 Å. There are a spread of Cr–Al bond distances ranging from 2.54–2.68 Å. In the third Cr site, Cr is bonded to two Y and ten Al atoms to form distorted CrY2Al10 cuboctahedra that share corners with three equivalent CrY2Al10 cuboctahedra, corners with three AlY2Al10 cuboctahedra, and faces with two equivalent AlY2Al8Cr2 cuboctahedra. There are a spread of Cr–Al bond distances ranging from 2.56–2.77 Å. There are nine inequivalent Al sites. In the first Al site, Al is bonded to two equivalent Y and ten Al atoms to form AlY2Al10 cuboctahedra that share corners with two equivalent CrY2Al10 cuboctahedra, corners with four AlY2Al10 cuboctahedra, and faces with two equivalent AlY2Al10 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.57–2.88 Å. In the second Al site, Al is bonded in a 10-coordinate geometry to one Y, three Cr, and six Al atoms. There are a spread of Al–Al bond distances ranging from 2.68–2.97 Å. In the third Al site, Al is bonded in a 12-coordinate geometry to one Y, two equivalent Cr, and nine Al atoms. There are a spread of Al–Al bond distances ranging from 2.73–3.09 Å. In the fourth Al site, Al is bonded in a 10-coordinate geometry to one Y, three Cr, and six Al atoms. There are a spread of Al–Al bond distances ranging from 2.69–2.95 Å. In the fifth Al site, Al is bonded in a 12-coordinate geometry to two equivalent Y, three Cr, and seven Al atoms. There are a spread of Al–Al bond distances ranging from 2.68–2.90 Å. In the sixth Al site, Al is bonded in a 12-coordinate geometry to two equivalent Y, two equivalent Cr, and eight Al atoms. There are a spread of Al–Al bond distances ranging from 2.69–2.91 Å. In the seventh Al site, Al is bonded in a 12-coordinate geometry to two equivalent Y, three Cr, and seven Al atoms. There are one shorter (2.68 Å) and one longer (2.91 Å) Al–Al bond lengths. In the eighth Al site, Al is bonded to two equivalent Y and ten Al atoms to form AlY2Al10 cuboctahedra that share corners with two equivalent CrY2Al10 cuboctahedra, corners with four AlY2Al10 cuboctahedra, and faces with two equivalent AlY2Al10 cuboctahedra. In the ninth Al site, Al is bonded to two Y, two equivalent Cr, and eight Al atoms to form distorted AlY2Al8Cr2 cuboctahedra that share a cornercorner with one CrY2Al10 cuboctahedra, corners with five AlY2Al10 cuboctahedra, and faces with two equivalent CrY2Al10 cuboctahedra.