Materials Data on Ce(Al10Cr)2 by Materials Project
CeCr2Al20 crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Ce is bonded in a 4-coordinate geometry to sixteen Al atoms. There are four shorter (3.13 Å) and twelve longer (3.21 Å) Ce–Al bond lengths. Cr is bonded to twelve Al atoms to form CrAl12 cuboctahedra that share corners with six equivalent CrAl12 cuboctahedra, edges with eighteen equivalent AlCeAl10Cr cuboctahedra, and faces with six equivalent AlCeAl10Cr cuboctahedra. There are six shorter (2.56 Å) and six longer (2.78 Å) Cr–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to two equivalent Cr and ten Al atoms. There are a spread of Al–Al bond distances ranging from 2.71–2.83 Å. In the second Al site, Al is bonded to one Ce, one Cr, and ten Al atoms to form distorted AlCeAl10Cr cuboctahedra that share corners with fifteen equivalent AlCeAl10Cr cuboctahedra, edges with two equivalent AlCeAl10Cr cuboctahedra, edges with three equivalent CrAl12 cuboctahedra, a faceface with one CrAl12 cuboctahedra, and faces with fifteen equivalent AlCeAl10Cr cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.71–3.09 Å. In the third Al site, Al is bonded in a distorted linear geometry to two equivalent Ce and twelve equivalent Al atoms.