Mg6CeAl crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ce(1), and one Al(1) atom. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ce(1), and two equivalent Al(1) atoms. In the third Mg site, Mg(3) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Al(1) atoms to form distorted MgMg10Al2 cuboctahedra that share corners with six equivalent Mg(3)Mg10Al2 cuboctahedra, faces with two equivalent Mg(3)Mg10Al2 cuboctahedra, and faces with six equivalent Ce(1)Mg10Al2 cuboctahedra. In the fourth Mg site, Mg(4) is bonded in a 12-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ce(1) atoms. Ce(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Al(1) atoms to form CeMg10Al2 cuboctahedra that share corners with six equivalent Ce(1)Mg10Al2 cuboctahedra, faces with two equivalent Ce(1)Mg10Al2 cuboctahedra, and faces with six equivalent Mg(3)Mg10Al2 cuboctahedra. Al(1) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), four equivalent Mg(2), and two equivalent Ce(1) atoms.
Mg6CeAl crystallizes in the orthorhombic Amm2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded in a 11-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ce(1), and one Al(1) atom. There is one shorter (3.26 Å) and one longer (3.35 Å) Mg(1)-Mg(1) bond length. Both Mg(1)-Mg(2) bond lengths are 3.27 Å. Both Mg(1)-Mg(3) bond lengths are 3.28 Å. Both Mg(1)-Mg(4) bond lengths are 3.23 Å. There is one shorter (3.38 Å) and one longer (3.42 Å) Mg(1)-Ce(1) bond length. The Mg(1)-Al(1) bond length is 3.33 Å. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Ce(1), and two equivalent Al(1) atoms. There is one shorter (3.17 Å) and one longer (3.44 Å) Mg(2)-Mg(2) bond length. There is one shorter (3.35 Å) and one longer (3.45 Å) Mg(2)-Mg(3) bond length. There is one shorter (3.31 Å) and one longer (3.49 Å) Mg(2)-Mg(4) bond length. Both Mg(2)-Ce(1) bond lengths are 3.30 Å. Both Mg(2)-Al(1) bond lengths are 3.21 Å. In the third Mg site, Mg(3) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Al(1) atoms to form distorted MgMg10Al2 cuboctahedra that share corners with six equivalent Mg(3)Mg10Al2 cuboctahedra, faces with two equivalent Mg(3)Mg10Al2 cuboctahedra, and faces with six equivalent Ce(1)Mg10Al2 cuboctahedra. Both Mg(3)-Mg(4) bond lengths are 3.30 Å. Both Mg(3)-Al(1) bond lengths are 3.29 Å. In the fourth Mg site, Mg(4) is bonded in a 12-coordinate geometry to two equivalent Mg(3), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Ce(1) atoms. Both Mg(4)-Ce(1) bond lengths are 3.30 Å. Ce(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(2), and two equivalent Al(1) atoms to form CeMg10Al2 cuboctahedra that share corners with six equivalent Ce(1)Mg10Al2 cuboctahedra, faces with two equivalent Ce(1)Mg10Al2 cuboctahedra, and faces with six equivalent Mg(3)Mg10Al2 cuboctahedra. Both Ce(1)-Al(1) bond lengths are 3.30 Å. Al(1) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Mg(3), four equivalent Mg(2), and two equivalent Ce(1) atoms.