Mg14CeC crystallizes in the hexagonal P-6m2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with six equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with two equivalent Ce(1)Mg12 cuboctahedra, edges with four equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Ce(1)Mg12 cuboctahedra, and faces with four equivalent Mg(1)Ce2Mg10 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Mg(4), four equivalent Mg(2), and four equivalent Mg(3) atoms. In the third Mg site, Mg(3) is bonded in a 1-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), one Ce(1), and one C(1) atom. In the fourth Mg site, Mg(4) is bonded to three equivalent Mg(1), three equivalent Mg(2), and six equivalent Mg(3) atoms to form distorted MgMg12 cuboctahedra that share corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with six equivalent Mg(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with three equivalent Mg(1)Ce2Mg10 cuboctahedra, and faces with three equivalent Ce(1)Mg12 cuboctahedra. Ce(1) is bonded to six equivalent Mg(1) and six equivalent Mg(3) atoms to form CeMg12 cuboctahedra that share corners with six equivalent Ce(1)Mg12 cuboctahedra, edges with six equivalent Mg(1)Ce2Mg10 cuboctahedra, faces with six equivalent Mg(1)Ce2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Mg12 cuboctahedra. C(1) is bonded in a 6-coordinate geometry to six equivalent Mg(3) atoms.
Mg14CeC crystallizes in the hexagonal P-6m2 space group. There are four inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(4), four equivalent Mg(1), four equivalent Mg(3), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with six equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with two equivalent Ce(1)Mg12 cuboctahedra, edges with four equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Ce(1)Mg12 cuboctahedra, and faces with four equivalent Mg(1)Ce2Mg10 cuboctahedra. Both Mg(1)-Mg(4) bond lengths are 3.04 Å. There are two shorter (2.97 Å) and two longer (3.31 Å) Mg(1)-Mg(1) bond lengths. All Mg(1)-Mg(3) bond lengths are 3.33 Å. Both Mg(1)-Ce(1) bond lengths are 3.14 Å. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Mg(4), four equivalent Mg(2), and four equivalent Mg(3) atoms. Both Mg(2)-Mg(4) bond lengths are 3.19 Å. There are two shorter (3.01 Å) and two longer (3.27 Å) Mg(2)-Mg(2) bond lengths. All Mg(2)-Mg(3) bond lengths are 2.95 Å. In the third Mg site, Mg(3) is bonded in a 1-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), one Ce(1), and one C(1) atom. Both Mg(3)-Mg(4) bond lengths are 3.17 Å. The Mg(3)-Ce(1) bond length is 3.27 Å. The Mg(3)-C(1) bond length is 2.83 Å. In the fourth Mg site, Mg(4) is bonded to three equivalent Mg(1), three equivalent Mg(2), and six equivalent Mg(3) atoms to form distorted MgMg12 cuboctahedra that share corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with six equivalent Mg(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with three equivalent Mg(1)Ce2Mg10 cuboctahedra, and faces with three equivalent Ce(1)Mg12 cuboctahedra. Ce(1) is bonded to six equivalent Mg(1) and six equivalent Mg(3) atoms to form CeMg12 cuboctahedra that share corners with six equivalent Ce(1)Mg12 cuboctahedra, edges with six equivalent Mg(1)Ce2Mg10 cuboctahedra, faces with six equivalent Mg(1)Ce2Mg10 cuboctahedra, and faces with six equivalent Mg(4)Mg12 cuboctahedra. C(1) is bonded in a 6-coordinate geometry to six equivalent Mg(3) atoms.