Mg14CeCo crystallizes in the hexagonal P-6m2 space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(4); four equivalent Mg(1); four Mg(3,3); and two equivalent Co(1) atoms to form distorted MgMg10Co2 cuboctahedra that share corners with four equivalent Ce(1)Mg12 cuboctahedra; corners with six equivalent Mg(1)Mg10Co2 cuboctahedra; corners with eight Mg(2,2)Ce2Mg10 cuboctahedra; edges with two equivalent Co(1)Mg12 cuboctahedra; edges with four equivalent Mg(1)Mg10Co2 cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Mg(2)Ce2Mg10 cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Co(1)Mg12 cuboctahedra; and faces with four equivalent Mg(1)Mg10Co2 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4); four Mg(2,2); four Mg(3,3); and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent Co(1)Mg12 cuboctahedra; corners with six equivalent Mg(2)Ce2Mg10 cuboctahedra; corners with eight equivalent Mg(1)Mg10Co2 cuboctahedra; edges with two equivalent Ce(1)Mg12 cuboctahedra; edges with four Mg(2,2)Ce2Mg10 cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Mg(1)Mg10Co2 cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Ce(1)Mg12 cuboctahedra; and faces with four Mg(2,2)Ce2Mg10 cuboctahedra. In the third Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(2), four equivalent Mg(3), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent Co(1)Mg12 cuboctahedra, corners with six equivalent Mg(2)Ce2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Mg10Co2 cuboctahedra, edges with two equivalent Ce(1)Mg12 cuboctahedra, edges with four equivalent Mg(2)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(1)Mg10Co2 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Ce(1)Mg12 cuboctahedra, and faces with four equivalent Mg(2)Ce2Mg10 cuboctahedra. In the fourth Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), four equivalent Mg(3), one Ce(1), and one Co(1) atom. In the fifth Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(1); two Mg(2,2); two equivalent Mg(4); four Mg(3,3); one Ce(1); and one Co(1) atom. In the sixth Mg site, Mg(4) is bonded to three equivalent Mg(1); three Mg(2,2); and six Mg(3,3) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(4)Mg12 cuboctahedra; edges with six Mg(2,2)Ce2Mg10 cuboctahedra; edges with six equivalent Mg(1)Mg10Co2 cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with three Mg(2,2)Ce2Mg10 cuboctahedra; faces with three equivalent Mg(1)Mg10Co2 cuboctahedra; faces with three equivalent Ce(1)Mg12 cuboctahedra; and faces with three equivalent Co(1)Mg12 cuboctahedra. Ce(1) is bonded to six Mg(2,2) and six Mg(3,3) atoms to form CeMg12 cuboctahedra that share corners with six equivalent Ce(1)Mg12 cuboctahedra; corners with twelve equivalent Mg(1)Mg10Co2 cuboctahedra; edges with six Mg(2,2)Ce2Mg10 cuboctahedra; faces with two equivalent Co(1)Mg12 cuboctahedra; faces with six Mg(2,2)Ce2Mg10 cuboctahedra; and faces with six equivalent Mg(4)Mg12 cuboctahedra. Co(1) is bonded to six equivalent Mg(1) and six Mg(3,3) atoms to form CoMg12 cuboctahedra that share corners with six equivalent Co(1)Mg12 cuboctahedra; corners with twelve Mg(2,2)Ce2Mg10 cuboctahedra; edges with six equivalent Mg(1)Mg10Co2 cuboctahedra; faces with two equivalent Ce(1)Mg12 cuboctahedra; faces with six equivalent Mg(1)Mg10Co2 cuboctahedra; and faces with six equivalent Mg(4)Mg12 cuboctahedra.
Mg14CeCo crystallizes in the hexagonal P-6m2 space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(4); four equivalent Mg(1); four Mg(3,3); and two equivalent Co(1) atoms to form distorted MgMg10Co2 cuboctahedra that share corners with four equivalent Ce(1)Mg12 cuboctahedra; corners with six equivalent Mg(1)Mg10Co2 cuboctahedra; corners with eight Mg(2,2)Ce2Mg10 cuboctahedra; edges with two equivalent Co(1)Mg12 cuboctahedra; edges with four equivalent Mg(1)Mg10Co2 cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Mg(2)Ce2Mg10 cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Co(1)Mg12 cuboctahedra; and faces with four equivalent Mg(1)Mg10Co2 cuboctahedra. Both Mg(1)-Mg(4) bond lengths are 3.19 Å. There are two shorter (3.19 Å) and two longer (3.24 Å) Mg(1)-Mg(1) bond lengths. All Mg(1)-Mg(3,3) bond lengths are 3.02 Å. Both Mg(1)-Co(1) bond lengths are 3.22 Å. In the second Mg site, Mg(2) is bonded to two equivalent Mg(4); four Mg(2,2); four Mg(3,3); and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent Co(1)Mg12 cuboctahedra; corners with six equivalent Mg(2)Ce2Mg10 cuboctahedra; corners with eight equivalent Mg(1)Mg10Co2 cuboctahedra; edges with two equivalent Ce(1)Mg12 cuboctahedra; edges with four Mg(2,2)Ce2Mg10 cuboctahedra; edges with four equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Mg(1)Mg10Co2 cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with two equivalent Ce(1)Mg12 cuboctahedra; and faces with four Mg(2,2)Ce2Mg10 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 3.10 Å. There are two shorter (3.11 Å) and two longer (3.33 Å) Mg(2)-Mg(2,2) bond lengths. All Mg(2)-Mg(3,3) bond lengths are 3.25 Å. Both Mg(2)-Ce(1) bond lengths are 3.22 Å. In the third Mg site, Mg(2) is bonded to two equivalent Mg(4), four equivalent Mg(2), four equivalent Mg(3), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with four equivalent Co(1)Mg12 cuboctahedra, corners with six equivalent Mg(2)Ce2Mg10 cuboctahedra, corners with eight equivalent Mg(1)Mg10Co2 cuboctahedra, edges with two equivalent Ce(1)Mg12 cuboctahedra, edges with four equivalent Mg(2)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Mg(1)Mg10Co2 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Ce(1)Mg12 cuboctahedra, and faces with four equivalent Mg(2)Ce2Mg10 cuboctahedra. Both Mg(2)-Mg(4) bond lengths are 3.10 Å. All Mg(2)-Mg(3) bond lengths are 3.25 Å. Both Mg(2)-Ce(1) bond lengths are 3.22 Å. In the fourth Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), four equivalent Mg(3), one Ce(1), and one Co(1) atom. Both Mg(3)-Mg(4) bond lengths are 3.22 Å. There are two shorter (3.16 Å) and two longer (3.27 Å) Mg(3)-Mg(3) bond lengths. The Mg(3)-Ce(1) bond length is 3.24 Å. The Mg(3)-Co(1) bond length is 2.98 Å. In the fifth Mg site, Mg(3) is bonded in a 12-coordinate geometry to two equivalent Mg(1); two Mg(2,2); two equivalent Mg(4); four Mg(3,3); one Ce(1); and one Co(1) atom. Both Mg(3)-Mg(4) bond lengths are 3.22 Å. There is one shorter (3.16 Å) and one longer (3.27 Å) Mg(3)-Mg(3) bond length. The Mg(3)-Ce(1) bond length is 3.24 Å. The Mg(3)-Co(1) bond length is 2.98 Å. In the sixth Mg site, Mg(4) is bonded to three equivalent Mg(1); three Mg(2,2); and six Mg(3,3) atoms to form MgMg12 cuboctahedra that share corners with six equivalent Mg(4)Mg12 cuboctahedra; edges with six Mg(2,2)Ce2Mg10 cuboctahedra; edges with six equivalent Mg(1)Mg10Co2 cuboctahedra; faces with two equivalent Mg(4)Mg12 cuboctahedra; faces with three Mg(2,2)Ce2Mg10 cuboctahedra; faces with three equivalent Mg(1)Mg10Co2 cuboctahedra; faces with three equivalent Ce(1)Mg12 cuboctahedra; and faces with three equivalent Co(1)Mg12 cuboctahedra. Ce(1) is bonded to six Mg(2,2) and six Mg(3,3) atoms to form CeMg12 cuboctahedra that share corners with six equivalent Ce(1)Mg12 cuboctahedra; corners with twelve equivalent Mg(1)Mg10Co2 cuboctahedra; edges with six Mg(2,2)Ce2Mg10 cuboctahedra; faces with two equivalent Co(1)Mg12 cuboctahedra; faces with six Mg(2,2)Ce2Mg10 cuboctahedra; and faces with six equivalent Mg(4)Mg12 cuboctahedra. Co(1) is bonded to six equivalent Mg(1) and six Mg(3,3) atoms to form CoMg12 cuboctahedra that share corners with six equivalent Co(1)Mg12 cuboctahedra; corners with twelve Mg(2,2)Ce2Mg10 cuboctahedra; edges with six equivalent Mg(1)Mg10Co2 cuboctahedra; faces with two equivalent Ce(1)Mg12 cuboctahedra; faces with six equivalent Mg(1)Mg10Co2 cuboctahedra; and faces with six equivalent Mg(4)Mg12 cuboctahedra.