Mg14CeB crystallizes in the orthorhombic Amm2 space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(7); four equivalent Mg(3); four Mg(5,5); 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(3)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(7)Mg12 cuboctahedra, faces with two equivalent Mg(7)Mg12 cuboctahedra, faces with two equivalent Ce(1)Mg12 cuboctahedra, and faces with four equivalent Mg(3)Ce2Mg10 cuboctahedra. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Mg(7); four equivalent Mg(4); and four Mg(5,5) atoms. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with six equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with two equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with two equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with two equivalent Ce(1)Mg12 cuboctahedra, edges with four equivalent Mg(7)Mg12 cuboctahedra, faces with two equivalent Mg(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(7)Mg12 cuboctahedra, and faces with two equivalent Ce(1)Mg12 cuboctahedra. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms. In the fifth Mg site, Mg(5) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), one Ce(1), and one B(1) atom. In the sixth Mg site, Mg(5) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), one Ce(1), and one B(1) atom. In the seventh Mg site, Mg(6) is bonded in a 12-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(7), four equivalent Mg(5), one Ce(1), and one B(1) atom. In the eighth Mg site, Mg(7) is bonded to one Mg(1), one Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(6), and four equivalent Mg(5) atoms to form distorted MgMg12 cuboctahedra that share corners with six equivalent Mg(7)Mg12 cuboctahedra, edges with two equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)Ce2Mg10 cuboctahedra,  a faceface with one Mg(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(7)Mg12 cuboctahedra, and faces with three equivalent Ce(1)Mg12 cuboctahedra. Ce(1) is bonded to two equivalent Mg(1); two equivalent Mg(6); four equivalent Mg(3); and four Mg(5,5) atoms to form CeMg12 cuboctahedra that share corners with six equivalent Ce(1)Mg12 cuboctahedra, edges with two equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(3)Ce2Mg10 cuboctahedra, and faces with six equivalent Mg(7)Mg12 cuboctahedra. B(1) is bonded in a 6-coordinate geometry to two equivalent Mg(6) and four Mg(5,5) atoms.
Mg14CeB crystallizes in the orthorhombic Amm2 space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(7); four equivalent Mg(3); four Mg(5,5); 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(3)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(7)Mg12 cuboctahedra, faces with two equivalent Mg(7)Mg12 cuboctahedra, faces with two equivalent Ce(1)Mg12 cuboctahedra, and faces with four equivalent Mg(3)Ce2Mg10 cuboctahedra. Both Mg(1)-Mg(7) bond lengths are 3.08 Å. There are two shorter (3.01 Å) and two longer (3.40 Å) Mg(1)-Mg(3) bond lengths. All Mg(1)-Mg(5,5) bond lengths are 3.32 Å. Both Mg(1)-Ce(1) bond lengths are 3.21 Å. In the second Mg site, Mg(2) is bonded in a 10-coordinate geometry to two equivalent Mg(7); four equivalent Mg(4); and four Mg(5,5) atoms. Both Mg(2)-Mg(7) bond lengths are 3.24 Å. There are two shorter (3.08 Å) and two longer (3.33 Å) Mg(2)-Mg(4) bond lengths. All Mg(2)-Mg(5,5) bond lengths are 3.02 Å. In the third Mg site, Mg(3) is bonded to two equivalent Mg(1), two equivalent Mg(3), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), and two equivalent Ce(1) atoms to form distorted MgCe2Mg10 cuboctahedra that share corners with six equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with two equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with two equivalent Mg(3)Ce2Mg10 cuboctahedra, edges with two equivalent Ce(1)Mg12 cuboctahedra, edges with four equivalent Mg(7)Mg12 cuboctahedra, faces with two equivalent Mg(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(7)Mg12 cuboctahedra, and faces with two equivalent Ce(1)Mg12 cuboctahedra. There is one shorter (3.01 Å) and one longer (3.40 Å) Mg(3)-Mg(3) bond length. Both Mg(3)-Mg(5) bond lengths are 3.32 Å. Both Mg(3)-Mg(6) bond lengths are 3.32 Å. Both Mg(3)-Mg(7) bond lengths are 3.08 Å. Both Mg(3)-Ce(1) bond lengths are 3.21 Å. In the fourth Mg site, Mg(4) is bonded in a 10-coordinate geometry to two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms. There is one shorter (3.08 Å) and one longer (3.33 Å) Mg(4)-Mg(4) bond length. Both Mg(4)-Mg(5) bond lengths are 3.02 Å. Both Mg(4)-Mg(6) bond lengths are 3.02 Å. Both Mg(4)-Mg(7) bond lengths are 3.24 Å. In the fifth Mg site, Mg(5) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), one Ce(1), and one B(1) atom. There is one shorter (3.07 Å) and one longer (3.34 Å) Mg(5)-Mg(5) bond length. There is one shorter (3.07 Å) and one longer (3.34 Å) Mg(5)-Mg(6) bond length. Both Mg(5)-Mg(7) bond lengths are 3.23 Å. The Mg(5)-Ce(1) bond length is 3.28 Å. The Mg(5)-B(1) bond length is 2.92 Å. In the sixth Mg site, Mg(5) is bonded in a 12-coordinate geometry to one Mg(1), one Mg(2), one Mg(3), one Mg(4), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), one Ce(1), and one B(1) atom. The Mg(5)-Mg(3) bond length is 3.32 Å. The Mg(5)-Mg(4) bond length is 3.02 Å. There is one shorter (3.07 Å) and one longer (3.34 Å) Mg(5)-Mg(5) bond length. There is one shorter (3.07 Å) and one longer (3.34 Å) Mg(5)-Mg(6) bond length. Both Mg(5)-Mg(7) bond lengths are 3.23 Å. The Mg(5)-Ce(1) bond length is 3.28 Å. The Mg(5)-B(1) bond length is 2.92 Å. In the seventh Mg site, Mg(6) is bonded in a 12-coordinate geometry to two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(7), four equivalent Mg(5), one Ce(1), and one B(1) atom. Both Mg(6)-Mg(7) bond lengths are 3.23 Å. The Mg(6)-Ce(1) bond length is 3.28 Å. The Mg(6)-B(1) bond length is 2.93 Å. In the eighth Mg site, Mg(7) is bonded to one Mg(1), one Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(6), and four equivalent Mg(5) atoms to form distorted MgMg12 cuboctahedra that share corners with six equivalent Mg(7)Mg12 cuboctahedra, edges with two equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)Ce2Mg10 cuboctahedra,  a faceface with one Mg(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(7)Mg12 cuboctahedra, and faces with three equivalent Ce(1)Mg12 cuboctahedra. Ce(1) is bonded to two equivalent Mg(1); two equivalent Mg(6); four equivalent Mg(3); and four Mg(5,5) atoms to form CeMg12 cuboctahedra that share corners with six equivalent Ce(1)Mg12 cuboctahedra, edges with two equivalent Mg(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(3)Ce2Mg10 cuboctahedra, and faces with six equivalent Mg(7)Mg12 cuboctahedra. B(1) is bonded in a 6-coordinate geometry to two equivalent Mg(6) and four Mg(5,5) atoms.