MgCe2 is beta-derived structured and crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded to two equivalent Mg(1), four equivalent Ce(2), and six equivalent Ce(1) atoms to form MgCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with seven equivalent Ce(1)Ce6Mg6 cuboctahedra, edges with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with six equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with six equivalent Ce(1)Ce6Mg6 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to six equivalent Mg(1), two equivalent Ce(2), and four equivalent Ce(1) atoms to form distorted CeCe6Mg6 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with seven equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with eleven equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with six equivalent Mg(1)Ce10Mg2 cuboctahedra, and faces with ten equivalent Ce(1)Ce6Mg6 cuboctahedra. In the second Ce site, Ce(2) is bonded to four equivalent Mg(1), two equivalent Ce(1), and six equivalent Ce(2) atoms to form CeCe8Mg4 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eleven equivalent Ce(1)Ce6Mg6 cuboctahedra, faces with four equivalent Ce(1)Ce6Mg6 cuboctahedra, faces with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra.
MgCe2 is beta-derived structured and crystallizes in the orthorhombic Cmcm space group. Mg(1) is bonded to two equivalent Mg(1), four equivalent Ce(2), and six equivalent Ce(1) atoms to form MgCe10Mg2 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with seven equivalent Ce(1)Ce6Mg6 cuboctahedra, edges with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with six equivalent Mg(1)Ce10Mg2 cuboctahedra, faces with six equivalent Ce(1)Ce6Mg6 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra. Both Mg(1)-Mg(1) bond lengths are 3.24 Å. There are two shorter (3.34 Å) and two longer (3.44 Å) Mg(1)-Ce(2) bond lengths. There are four shorter (3.37 Å) and two longer (3.55 Å) Mg(1)-Ce(1) bond lengths. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to six equivalent Mg(1), two equivalent Ce(2), and four equivalent Ce(1) atoms to form distorted CeCe6Mg6 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with seven equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with eleven equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with six equivalent Mg(1)Ce10Mg2 cuboctahedra, and faces with ten equivalent Ce(1)Ce6Mg6 cuboctahedra. Both Ce(1)-Ce(2) bond lengths are 3.22 Å. There are two shorter (3.24 Å) and two longer (3.66 Å) Ce(1)-Ce(1) bond lengths. In the second Ce site, Ce(2) is bonded to four equivalent Mg(1), two equivalent Ce(1), and six equivalent Ce(2) atoms to form CeCe8Mg4 cuboctahedra that share corners with six equivalent Mg(1)Ce10Mg2 cuboctahedra, corners with six equivalent Ce(1)Ce6Mg6 cuboctahedra, corners with six equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with three equivalent Mg(1)Ce10Mg2 cuboctahedra, edges with four equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eleven equivalent Ce(1)Ce6Mg6 cuboctahedra, faces with four equivalent Ce(1)Ce6Mg6 cuboctahedra, faces with eight equivalent Mg(1)Ce10Mg2 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra. There are two shorter (3.24 Å) and four longer (3.40 Å) Ce(2)-Ce(2) bond lengths.