MgCe3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Ce(1) and eight equivalent Ce(2) atoms to form MgCe12 cuboctahedra that share corners with four equivalent Mg(1)Ce12 cuboctahedra, corners with eight equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Ce12 cuboctahedra, edges with sixteen equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Mg(1)Ce12 cuboctahedra, faces with six equivalent Ce(1)Ce8Mg4 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 four equivalent Mg(1) and eight equivalent Ce(2) atoms to form CeCe8Mg4 cuboctahedra that share corners with four equivalent Ce(1)Ce8Mg4 cuboctahedra, corners with eight equivalent Mg(1)Ce12 cuboctahedra, edges with eight equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with sixteen equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(1)Ce8Mg4 cuboctahedra, faces with six equivalent Mg(1)Ce12 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra. In the second Ce site, Ce(2) is bonded to four equivalent Mg(1), four equivalent Ce(1), and four equivalent Ce(2) atoms to form CeCe8Mg4 cuboctahedra that share corners with twelve equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Ce12 cuboctahedra, edges with eight equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Mg(1)Ce12 cuboctahedra, faces with four equivalent Ce(1)Ce8Mg4 cuboctahedra, and faces with ten equivalent Ce(2)Ce8Mg4 cuboctahedra.
MgCe3 is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Ce(1) and eight equivalent Ce(2) atoms to form MgCe12 cuboctahedra that share corners with four equivalent Mg(1)Ce12 cuboctahedra, corners with eight equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Ce12 cuboctahedra, edges with sixteen equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Mg(1)Ce12 cuboctahedra, faces with six equivalent Ce(1)Ce8Mg4 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra. All Mg(1)-Ce(1) bond lengths are 3.36 Å. All Mg(1)-Ce(2) bond lengths are 3.40 Å. There are two inequivalent Ce sites. In the first Ce site, Ce(1) is bonded to four equivalent Mg(1) and eight equivalent Ce(2) atoms to form CeCe8Mg4 cuboctahedra that share corners with four equivalent Ce(1)Ce8Mg4 cuboctahedra, corners with eight equivalent Mg(1)Ce12 cuboctahedra, edges with eight equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with sixteen equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Ce(1)Ce8Mg4 cuboctahedra, faces with six equivalent Mg(1)Ce12 cuboctahedra, and faces with eight equivalent Ce(2)Ce8Mg4 cuboctahedra. All Ce(1)-Ce(2) bond lengths are 3.40 Å. In the second Ce site, Ce(2) is bonded to four equivalent Mg(1), four equivalent Ce(1), and four equivalent Ce(2) atoms to form CeCe8Mg4 cuboctahedra that share corners with twelve equivalent Ce(2)Ce8Mg4 cuboctahedra, edges with eight equivalent Mg(1)Ce12 cuboctahedra, edges with eight equivalent Ce(1)Ce8Mg4 cuboctahedra, edges with eight equivalent Ce(2)Ce8Mg4 cuboctahedra, faces with four equivalent Mg(1)Ce12 cuboctahedra, faces with four equivalent Ce(1)Ce8Mg4 cuboctahedra, and faces with ten equivalent Ce(2)Ce8Mg4 cuboctahedra. All Ce(2)-Ce(2) bond lengths are 3.36 Å.