Mg14CeLa crystallizes in the orthorhombic Amm2 space group. There are seven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), two equivalent Mg(6), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Ce(1)La2Mg10 cuboctahedra, corners with six equivalent Mg(1)Mg12 cuboctahedra, corners with eight equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with four equivalent Mg(6)LaMg11 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, edges with eight equivalent Mg(5)LaCeMg10 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, faces with two equivalent La(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(7)CeMg11 cuboctahedra. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(7), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent La(1)Ce2Mg10 cuboctahedra, corners with six equivalent Mg(2)Mg12 cuboctahedra, corners with eight equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(7)CeMg11 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, edges with eight equivalent Mg(5)LaCeMg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Ce(1)La2Mg10 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(6)LaMg11 cuboctahedra. In the third Mg site, Mg(3) is bonded to two equivalent Mg(3), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), two equivalent Ce(1), and two equivalent La(1) atoms to form distorted MgLa2Ce2Mg8 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra, corners with four equivalent Mg(2)Mg12 cuboctahedra, corners with four equivalent Mg(4)Mg12 cuboctahedra, corners with six equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Ce(1)La2Mg10 cuboctahedra, edges with two equivalent La(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(7)CeMg11 cuboctahedra, edges with four equivalent Mg(5)LaCeMg10 cuboctahedra, edges with four equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Ce(1)La2Mg10 cuboctahedra, faces with two equivalent La(1)Ce2Mg10 cuboctahedra, and faces with eight equivalent Mg(5)LaCeMg10 cuboctahedra. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, corners with four equivalent Ce(1)La2Mg10 cuboctahedra, corners with four equivalent La(1)Ce2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(4)Mg12 cuboctahedra, edges with four equivalent Mg(7)CeMg11 cuboctahedra, edges with four equivalent Mg(5)LaCeMg10 cuboctahedra, edges with four equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, and faces with eight equivalent Mg(5)LaCeMg10 cuboctahedra. In the fifth Mg site, Mg(5) is bonded 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 La(1) atom to form MgLaCeMg10 cuboctahedra that share corners with four equivalent Mg(7)CeMg11 cuboctahedra, corners with four equivalent Mg(6)LaMg11 cuboctahedra, corners with ten equivalent Mg(5)LaCeMg10 cuboctahedra, edges with two equivalent Mg(7)CeMg11 cuboctahedra, edges with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Mg(5)LaCeMg10 cuboctahedra, edges with two equivalent Mg(6)LaMg11 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Ce(1)La2Mg10 cuboctahedra, edges with two equivalent La(1)Ce2Mg10 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra,  a faceface with one Mg(2)Mg12 cuboctahedra,  a faceface with one Ce(1)La2Mg10 cuboctahedra,  a faceface with one La(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, and faces with four equivalent Mg(4)Mg12 cuboctahedra. In the sixth Mg site, Mg(6) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(7), four equivalent Mg(5), and one La(1) atom to form MgLaMg11 cuboctahedra that share corners with four equivalent Mg(7)CeMg11 cuboctahedra, corners with six equivalent Mg(6)LaMg11 cuboctahedra, corners with eight equivalent Mg(5)LaCeMg10 cuboctahedra, edges with two equivalent Mg(7)CeMg11 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent La(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with four equivalent Mg(5)LaCeMg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra,  a faceface with one La(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with three equivalent Mg(2)Mg12 cuboctahedra, faces with three equivalent Ce(1)La2Mg10 cuboctahedra, and faces with four equivalent Mg(5)LaCeMg10 cuboctahedra. In the seventh Mg site, Mg(7) is bonded to one Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(6), four equivalent Mg(5), and one Ce(1) atom to form MgCeMg11 cuboctahedra that share corners with four equivalent Mg(6)LaMg11 cuboctahedra, corners with six equivalent Mg(7)CeMg11 cuboctahedra, corners with eight equivalent Mg(5)LaCeMg10 cuboctahedra, edges with two equivalent Mg(6)LaMg11 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Ce(1)La2Mg10 cuboctahedra, edges with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with four equivalent Mg(5)LaCeMg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Mg(2)Mg12 cuboctahedra,  a faceface with one Ce(1)La2Mg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with three equivalent Mg(1)Mg12 cuboctahedra, faces with three equivalent La(1)Ce2Mg10 cuboctahedra, and faces with four equivalent Mg(5)LaCeMg10 cuboctahedra. Ce(1) is bonded to two equivalent Mg(7), four equivalent Mg(3), four equivalent Mg(5), and two equivalent La(1) atoms to form CeLa2Mg10 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra, corners with six equivalent Ce(1)La2Mg10 cuboctahedra, corners with eight equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent La(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(7)CeMg11 cuboctahedra, edges with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with eight equivalent Mg(5)LaCeMg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, faces with two equivalent La(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, and faces with six equivalent Mg(6)LaMg11 cuboctahedra. La(1) is bonded to two equivalent Mg(6), four equivalent Mg(3), four equivalent Mg(5), and two equivalent Ce(1) atoms to form LaCe2Mg10 cuboctahedra that share corners with four equivalent Mg(2)Mg12 cuboctahedra, corners with six equivalent La(1)Ce2Mg10 cuboctahedra, corners with eight equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Ce(1)La2Mg10 cuboctahedra, edges with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with four equivalent Mg(6)LaMg11 cuboctahedra, edges with eight equivalent Mg(5)LaCeMg10 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Ce(1)La2Mg10 cuboctahedra, faces with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, and faces with six equivalent Mg(7)CeMg11 cuboctahedra.
Mg14CeLa crystallizes in the orthorhombic Amm2 space group. There are seven inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to two equivalent Mg(2), two equivalent Mg(6), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Ce(1)La2Mg10 cuboctahedra, corners with six equivalent Mg(1)Mg12 cuboctahedra, corners with eight equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with four equivalent Mg(6)LaMg11 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, edges with eight equivalent Mg(5)LaCeMg10 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, faces with two equivalent La(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(7)CeMg11 cuboctahedra. Both Mg(1)-Mg(2) bond lengths are 3.23 Å. Both Mg(1)-Mg(6) bond lengths are 3.25 Å. All Mg(1)-Mg(4) bond lengths are 3.31 Å. All Mg(1)-Mg(5) bond lengths are 3.15 Å. In the second Mg site, Mg(2) is bonded to two equivalent Mg(1), two equivalent Mg(7), four equivalent Mg(4), and four equivalent Mg(5) atoms to form MgMg12 cuboctahedra that share corners with four equivalent La(1)Ce2Mg10 cuboctahedra, corners with six equivalent Mg(2)Mg12 cuboctahedra, corners with eight equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with four equivalent Mg(7)CeMg11 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra, edges with eight equivalent Mg(5)LaCeMg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Ce(1)La2Mg10 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, faces with four equivalent Mg(4)Mg12 cuboctahedra, and faces with six equivalent Mg(6)LaMg11 cuboctahedra. Both Mg(2)-Mg(7) bond lengths are 3.25 Å. There are two shorter (3.30 Å) and two longer (3.31 Å) Mg(2)-Mg(4) bond lengths. All Mg(2)-Mg(5) bond lengths are 3.14 Å. In the third Mg site, Mg(3) is bonded to two equivalent Mg(3), two equivalent Mg(5), two equivalent Mg(6), two equivalent Mg(7), two equivalent Ce(1), and two equivalent La(1) atoms to form distorted MgLa2Ce2Mg8 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra, corners with four equivalent Mg(2)Mg12 cuboctahedra, corners with four equivalent Mg(4)Mg12 cuboctahedra, corners with six equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Ce(1)La2Mg10 cuboctahedra, edges with two equivalent La(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(7)CeMg11 cuboctahedra, edges with four equivalent Mg(5)LaCeMg10 cuboctahedra, edges with four equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with two equivalent Ce(1)La2Mg10 cuboctahedra, faces with two equivalent La(1)Ce2Mg10 cuboctahedra, and faces with eight equivalent Mg(5)LaCeMg10 cuboctahedra. Both Mg(3)-Mg(3) bond lengths are 3.23 Å. Both Mg(3)-Mg(5) bond lengths are 3.37 Å. Both Mg(3)-Mg(6) bond lengths are 3.29 Å. Both Mg(3)-Mg(7) bond lengths are 3.28 Å. There is one shorter (3.28 Å) and one longer (3.33 Å) Mg(3)-Ce(1) bond length. There is one shorter (3.27 Å) and one longer (3.34 Å) Mg(3)-La(1) bond length. In the fourth Mg site, Mg(4) is bonded to two equivalent Mg(1), two equivalent Mg(2), two equivalent Mg(4), two equivalent Mg(5), two equivalent Mg(6), and two equivalent Mg(7) atoms to form MgMg12 cuboctahedra that share corners with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, corners with four equivalent Ce(1)La2Mg10 cuboctahedra, corners with four equivalent La(1)Ce2Mg10 cuboctahedra, corners with six equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(4)Mg12 cuboctahedra, edges with four equivalent Mg(7)CeMg11 cuboctahedra, edges with four equivalent Mg(5)LaCeMg10 cuboctahedra, edges with four equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, and faces with eight equivalent Mg(5)LaCeMg10 cuboctahedra. There is one shorter (3.22 Å) and one longer (3.24 Å) Mg(4)-Mg(4) bond length. Both Mg(4)-Mg(5) bond lengths are 3.14 Å. Both Mg(4)-Mg(6) bond lengths are 3.18 Å. Both Mg(4)-Mg(7) bond lengths are 3.20 Å. In the fifth Mg site, Mg(5) is bonded 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 La(1) atom to form MgLaCeMg10 cuboctahedra that share corners with four equivalent Mg(7)CeMg11 cuboctahedra, corners with four equivalent Mg(6)LaMg11 cuboctahedra, corners with ten equivalent Mg(5)LaCeMg10 cuboctahedra, edges with two equivalent Mg(7)CeMg11 cuboctahedra, edges with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with two equivalent Mg(5)LaCeMg10 cuboctahedra, edges with two equivalent Mg(6)LaMg11 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Ce(1)La2Mg10 cuboctahedra, edges with two equivalent La(1)Ce2Mg10 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra,  a faceface with one Mg(2)Mg12 cuboctahedra,  a faceface with one Ce(1)La2Mg10 cuboctahedra,  a faceface with one La(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, and faces with four equivalent Mg(4)Mg12 cuboctahedra. There is one shorter (3.20 Å) and one longer (3.26 Å) Mg(5)-Mg(5) bond length. There is one shorter (3.23 Å) and one longer (3.38 Å) Mg(5)-Mg(6) bond length. There is one shorter (3.26 Å) and one longer (3.35 Å) Mg(5)-Mg(7) bond length. The Mg(5)-Ce(1) bond length is 3.36 Å. The Mg(5)-La(1) bond length is 3.37 Å. In the sixth Mg site, Mg(6) is bonded to one Mg(1), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(7), four equivalent Mg(5), and one La(1) atom to form MgLaMg11 cuboctahedra that share corners with four equivalent Mg(7)CeMg11 cuboctahedra, corners with six equivalent Mg(6)LaMg11 cuboctahedra, corners with eight equivalent Mg(5)LaCeMg10 cuboctahedra, edges with two equivalent Mg(7)CeMg11 cuboctahedra, edges with two equivalent Mg(1)Mg12 cuboctahedra, edges with two equivalent La(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with four equivalent Mg(5)LaCeMg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Mg(1)Mg12 cuboctahedra,  a faceface with one La(1)Ce2Mg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with three equivalent Mg(2)Mg12 cuboctahedra, faces with three equivalent Ce(1)La2Mg10 cuboctahedra, and faces with four equivalent Mg(5)LaCeMg10 cuboctahedra. Both Mg(6)-Mg(7) bond lengths are 3.23 Å. The Mg(6)-La(1) bond length is 3.38 Å. In the seventh Mg site, Mg(7) is bonded to one Mg(2), two equivalent Mg(3), two equivalent Mg(4), two equivalent Mg(6), four equivalent Mg(5), and one Ce(1) atom to form MgCeMg11 cuboctahedra that share corners with four equivalent Mg(6)LaMg11 cuboctahedra, corners with six equivalent Mg(7)CeMg11 cuboctahedra, corners with eight equivalent Mg(5)LaCeMg10 cuboctahedra, edges with two equivalent Mg(6)LaMg11 cuboctahedra, edges with two equivalent Mg(2)Mg12 cuboctahedra, edges with two equivalent Ce(1)La2Mg10 cuboctahedra, edges with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with four equivalent Mg(5)LaCeMg10 cuboctahedra, edges with four equivalent Mg(4)Mg12 cuboctahedra,  a faceface with one Mg(2)Mg12 cuboctahedra,  a faceface with one Ce(1)La2Mg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(4)Mg12 cuboctahedra, faces with three equivalent Mg(1)Mg12 cuboctahedra, faces with three equivalent La(1)Ce2Mg10 cuboctahedra, and faces with four equivalent Mg(5)LaCeMg10 cuboctahedra. The Mg(7)-Ce(1) bond length is 3.34 Å. Ce(1) is bonded to two equivalent Mg(7), four equivalent Mg(3), four equivalent Mg(5), and two equivalent La(1) atoms to form CeLa2Mg10 cuboctahedra that share corners with four equivalent Mg(1)Mg12 cuboctahedra, corners with six equivalent Ce(1)La2Mg10 cuboctahedra, corners with eight equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent La(1)Ce2Mg10 cuboctahedra, edges with four equivalent Mg(7)CeMg11 cuboctahedra, edges with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with eight equivalent Mg(5)LaCeMg10 cuboctahedra, faces with two equivalent Mg(7)CeMg11 cuboctahedra, faces with two equivalent Mg(2)Mg12 cuboctahedra, faces with two equivalent La(1)Ce2Mg10 cuboctahedra, faces with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, and faces with six equivalent Mg(6)LaMg11 cuboctahedra. Both Ce(1)-La(1) bond lengths are 3.23 Å. La(1) is bonded to two equivalent Mg(6), four equivalent Mg(3), four equivalent Mg(5), and two equivalent Ce(1) atoms to form LaCe2Mg10 cuboctahedra that share corners with four equivalent Mg(2)Mg12 cuboctahedra, corners with six equivalent La(1)Ce2Mg10 cuboctahedra, corners with eight equivalent Mg(4)Mg12 cuboctahedra, edges with two equivalent Ce(1)La2Mg10 cuboctahedra, edges with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, edges with four equivalent Mg(6)LaMg11 cuboctahedra, edges with eight equivalent Mg(5)LaCeMg10 cuboctahedra, faces with two equivalent Mg(6)LaMg11 cuboctahedra, faces with two equivalent Mg(1)Mg12 cuboctahedra, faces with two equivalent Ce(1)La2Mg10 cuboctahedra, faces with four equivalent Mg(3)La2Ce2Mg8 cuboctahedra, faces with four equivalent Mg(5)LaCeMg10 cuboctahedra, and faces with six equivalent Mg(7)CeMg11 cuboctahedra.