Mg6CeCu 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 Cu(1) atom. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Cu(1) atoms. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to one Mg(4), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Ce(1), and two equivalent Cu(1) atoms. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), four equivalent Mg(1), and two equivalent Ce(1) atoms. Ce(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Cu(1) atoms to form a mixture of distorted face and corner-sharing CeMg10Cu2 cuboctahedra. Cu(1) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and two equivalent Ce(1) atoms.
Mg6CeCu 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 Cu(1) atom. There is one shorter (3.10 Å) and one longer (3.24 Å) Mg(1)-Mg(1) bond length. There is one shorter (3.35 Å) and one longer (3.38 Å) Mg(1)-Mg(2) bond length. Both Mg(1)-Mg(3) bond lengths are 2.98 Å. Both Mg(1)-Mg(4) bond lengths are 3.12 Å. Both Mg(1)-Ce(1) bond lengths are 3.29 Å. The Mg(1)-Cu(1) bond length is 3.04 Å. In the second Mg site, Mg(2) is bonded in a 12-coordinate geometry to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Cu(1) atoms. Both Mg(2)-Mg(4) bond lengths are 3.12 Å. All Mg(2)-Mg(3) bond lengths are 3.21 Å. Both Mg(2)-Cu(1) bond lengths are 3.19 Å. In the third Mg site, Mg(3) is bonded in a 11-coordinate geometry to one Mg(4), two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(3), two equivalent Ce(1), and two equivalent Cu(1) atoms. The Mg(3)-Mg(4) bond length is 3.17 Å. There is one shorter (3.12 Å) and one longer (3.22 Å) Mg(3)-Mg(3) bond length. There is one shorter (3.21 Å) and one longer (3.52 Å) Mg(3)-Ce(1) bond length. Both Mg(3)-Cu(1) bond lengths are 3.07 Å. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Mg(2), two equivalent Mg(3), four equivalent Mg(1), and two equivalent Ce(1) atoms. Both Mg(4)-Ce(1) bond lengths are 3.19 Å. Ce(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Cu(1) atoms to form a mixture of distorted face and corner-sharing CeMg10Cu2 cuboctahedra. Both Ce(1)-Cu(1) bond lengths are 3.09 Å. Cu(1) is bonded in a 10-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), four equivalent Mg(3), and two equivalent Ce(1) atoms.