MgCe5 is beta-derived structured and crystallizes in the orthorhombic Amm2 space group. Mg(1) is bonded to two equivalent Mg(1), two equivalent Ce(3), two equivalent Ce(4), two equivalent Ce(5), and four equivalent Ce(2) atoms to form MgCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(4)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(1)Ce12 cuboctahedra, faces with two equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(1)Ce12 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, and faces with six equivalent Ce(3)Ce10Mg2 cuboctahedra. There are five inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(3), two equivalent Ce(5), and four equivalent Ce(4) atoms to form CeCe12 cuboctahedra that share corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce12 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with four equivalent Ce(4)Ce10Mg2 cuboctahedra, edges with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(1)Ce12 cuboctahedra, and faces with six equivalent Ce(5)Ce10Mg2 cuboctahedra. In the second Ce site, Ce(2) is bonded to four equivalent Mg(1), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(3), and two equivalent Ce(4) atoms to form distorted CeCe8Mg4 cuboctahedra that share corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce12 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(1)Ce12 cuboctahedra, edges with four equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with eight equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(1)Ce12 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, and faces with six equivalent Ce(4)Ce10Mg2 cuboctahedra. In the third Ce site, Ce(3) is bonded to two equivalent Mg(1), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(3), and four equivalent Ce(5) atoms to form CeCe10Mg2 cuboctahedra that share corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce12 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(1)Ce12 cuboctahedra, edges with three equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with four equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with eight equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(1)Ce12 cuboctahedra, faces with two equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(5)Ce10Mg2 cuboctahedra, and faces with six equivalent Mg(1)Ce10Mg2 cuboctahedra. In the fourth Ce site, Ce(4) is bonded to two equivalent Mg(1), two equivalent Ce(2), two equivalent Ce(4), two equivalent Ce(5), and four equivalent Ce(1) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(1)Ce12 cuboctahedra, edges with eight equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(1)Ce12 cuboctahedra, and faces with six equivalent Ce(2)Ce8Mg4 cuboctahedra. In the fifth Ce site, Ce(5) is bonded to two equivalent Mg(1), two equivalent Ce(1), two equivalent Ce(4), two equivalent Ce(5), and four equivalent Ce(3) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(4)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with eight equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with two equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(5)Ce10Mg2 cuboctahedra, and faces with six equivalent Ce(1)Ce12 cuboctahedra.
MgCe5 is beta-derived structured and crystallizes in the orthorhombic Amm2 space group. Mg(1) is bonded to two equivalent Mg(1), two equivalent Ce(3), two equivalent Ce(4), two equivalent Ce(5), and four equivalent Ce(2) atoms to form MgCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(4)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(1)Ce12 cuboctahedra, faces with two equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(1)Ce12 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, and faces with six equivalent Ce(3)Ce10Mg2 cuboctahedra. Both Mg(1)-Mg(1) bond lengths are 3.41 Å. Both Mg(1)-Ce(3) bond lengths are 3.56 Å. Both Mg(1)-Ce(4) bond lengths are 3.59 Å. Both Mg(1)-Ce(5) bond lengths are 3.49 Å. All Mg(1)-Ce(2) bond lengths are 3.54 Å. There are five inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(3), two equivalent Ce(5), and four equivalent Ce(4) atoms to form CeCe12 cuboctahedra that share corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce12 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with four equivalent Ce(4)Ce10Mg2 cuboctahedra, edges with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(1)Ce12 cuboctahedra, and faces with six equivalent Ce(5)Ce10Mg2 cuboctahedra. Both Ce(1)-Ce(1) bond lengths are 3.41 Å. Both Ce(1)-Ce(2) bond lengths are 3.35 Å. Both Ce(1)-Ce(3) bond lengths are 3.59 Å. Both Ce(1)-Ce(5) bond lengths are 3.62 Å. All Ce(1)-Ce(4) bond lengths are 3.48 Å. In the second Ce site, Ce(2) is bonded to four equivalent Mg(1), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(3), and two equivalent Ce(4) atoms to form distorted CeCe8Mg4 cuboctahedra that share corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce12 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(1)Ce12 cuboctahedra, edges with four equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with eight equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(1)Ce12 cuboctahedra, faces with four equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, and faces with six equivalent Ce(4)Ce10Mg2 cuboctahedra. Both Ce(2)-Ce(2) bond lengths are 3.41 Å. Both Ce(2)-Ce(3) bond lengths are 3.34 Å. Both Ce(2)-Ce(4) bond lengths are 3.73 Å. In the third Ce site, Ce(3) is bonded to two equivalent Mg(1), two equivalent Ce(1), two equivalent Ce(2), two equivalent Ce(3), and four equivalent Ce(5) atoms to form CeCe10Mg2 cuboctahedra that share corners with six equivalent Ce(3)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce12 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(1)Ce12 cuboctahedra, edges with three equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with four equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with eight equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(1)Ce12 cuboctahedra, faces with two equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(5)Ce10Mg2 cuboctahedra, and faces with six equivalent Mg(1)Ce10Mg2 cuboctahedra. Both Ce(3)-Ce(3) bond lengths are 3.41 Å. All Ce(3)-Ce(5) bond lengths are 3.59 Å. In the fourth Ce site, Ce(4) is bonded to two equivalent Mg(1), two equivalent Ce(2), two equivalent Ce(4), two equivalent Ce(5), and four equivalent Ce(1) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(1)Ce12 cuboctahedra, edges with eight equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(5)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(1)Ce12 cuboctahedra, and faces with six equivalent Ce(2)Ce8Mg4 cuboctahedra. Both Ce(4)-Ce(4) bond lengths are 3.41 Å. Both Ce(4)-Ce(5) bond lengths are 3.20 Å. In the fifth Ce site, Ce(5) is bonded to two equivalent Mg(1), two equivalent Ce(1), two equivalent Ce(4), two equivalent Ce(5), and four equivalent Ce(3) atoms to form distorted CeCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(4)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(5)Ce10Mg2 cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with three equivalent Ce(4)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(3)Ce10Mg2 cuboctahedra, edges with eight equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with two equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(4)Ce10Mg2 cuboctahedra, faces with two equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(3)Ce10Mg2 cuboctahedra, faces with four equivalent Ce(5)Ce10Mg2 cuboctahedra, and faces with six equivalent Ce(1)Ce12 cuboctahedra. Both Ce(5)-Ce(5) bond lengths are 3.41 Å.