Materials Data on CeU3Al8 by Materials Project
U3CeAl8 is Hexagonal Laves-derived structured and crystallizes in the trigonal R3m space group. The structure is three-dimensional. there are three inequivalent U sites. In the first U site, U is bonded in a 12-coordinate geometry to four U and twelve Al atoms. There are one shorter (3.24 Å) and three longer (3.36 Å) U–U bond lengths. There are six shorter (3.20 Å) and six longer (3.24 Å) U–Al bond lengths. In the second U site, U is bonded in a 12-coordinate geometry to three equivalent U, one Ce, and twelve Al atoms. The U–Ce bond length is 3.47 Å. There are a spread of U–Al bond distances ranging from 3.14–3.26 Å. In the third U site, U is bonded in a 9-coordinate geometry to one U, three equivalent Ce, and twelve Al atoms. All U–Ce bond lengths are 3.40 Å. There are a spread of U–Al bond distances ranging from 3.19–3.33 Å. Ce is bonded in a 12-coordinate geometry to four U and twelve Al atoms. There are a spread of Ce–Al bond distances ranging from 3.22–3.25 Å. There are four inequivalent Al sites. In the first Al site, Al is bonded to four U, two equivalent Ce, and six Al atoms to form a mixture of corner, edge, and face-sharing AlCe2U4Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.74–2.78 Å. In the second Al site, Al is bonded to five U, one Ce, and six Al atoms to form a mixture of corner, edge, and face-sharing AlCeU5Al6 cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.74–2.76 Å. In the third Al site, Al is bonded to three equivalent U, three equivalent Ce, and six Al atoms to form AlCe3U3Al6 cuboctahedra that share corners with eighteen AlCe2U4Al6 cuboctahedra, edges with six equivalent AlCe3U3Al6 cuboctahedra, and faces with eighteen AlCe2U4Al6 cuboctahedra. In the fourth Al site, Al is bonded to six U and six Al atoms to form AlU6Al6 cuboctahedra that share corners with eighteen AlCe2U4Al6 cuboctahedra, edges with six equivalent AlU6Al6 cuboctahedra, and faces with eighteen AlCe2U4Al6 cuboctahedra.