CeCu4Al crystallizes in the hexagonal P-6m2 space group. Ce(1) is bonded in a 18-coordinate geometry to three equivalent Cu(1), twelve equivalent Cu(2), and three equivalent Al(1) atoms. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 9-coordinate geometry to three equivalent Ce(1) and six equivalent Cu(2) atoms. In the second Cu site, Cu(2) is bonded to four equivalent Ce(1), two equivalent Cu(1), four equivalent Cu(2), and two equivalent Al(1) atoms to form a mixture of distorted face, corner, and edge-sharing CuCe4Al2Cu6 cuboctahedra. Al(1) is bonded in a 9-coordinate geometry to three equivalent Ce(1) and six equivalent Cu(2) atoms.
CeCu4Al crystallizes in the hexagonal P-6m2 space group. Ce(1) is bonded in a 18-coordinate geometry to three equivalent Cu(1), twelve equivalent Cu(2), and three equivalent Al(1) atoms. All Ce(1)-Cu(1) bond lengths are 3.30 Å. All Ce(1)-Cu(2) bond lengths are 3.63 Å. All Ce(1)-Al(1) bond lengths are 3.30 Å. There are two inequivalent Cu sites. In the first Cu site, Cu(1) is bonded in a 9-coordinate geometry to three equivalent Ce(1) and six equivalent Cu(2) atoms. All Cu(1)-Cu(2) bond lengths are 2.77 Å. In the second Cu site, Cu(2) is bonded to four equivalent Ce(1), two equivalent Cu(1), four equivalent Cu(2), and two equivalent Al(1) atoms to form a mixture of distorted face, corner, and edge-sharing CuCe4Al2Cu6 cuboctahedra. There are two shorter (2.84 Å) and two longer (2.88 Å) Cu(2)-Cu(2) bond lengths. Both Cu(2)-Al(1) bond lengths are 2.78 Å. Al(1) is bonded in a 9-coordinate geometry to three equivalent Ce(1) and six equivalent Cu(2) atoms.