MgZn2 crystallizes in the hexagonal P-62m space group. Mg(1) is bonded to three equivalent Mg(1), three equivalent Zn(2), and six equivalent Zn(1) atoms to form MgMg3Zn9 cuboctahedra that share corners with nine equivalent Mg(1)Mg3Zn9 cuboctahedra, corners with nine equivalent Zn(2)Mg6Zn6 cuboctahedra, edges with six equivalent Mg(1)Mg3Zn9 cuboctahedra, edges with twelve equivalent Zn(1)Mg4Zn8 cuboctahedra, faces with three equivalent Zn(2)Mg6Zn6 cuboctahedra, faces with five equivalent Mg(1)Mg3Zn9 cuboctahedra, and faces with twelve equivalent Zn(1)Mg4Zn8 cuboctahedra. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to four equivalent Mg(1), two equivalent Zn(2), and six equivalent Zn(1) atoms to form distorted ZnMg4Zn8 cuboctahedra that share corners with eighteen equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with four equivalent Zn(2)Mg6Zn6 cuboctahedra, edges with six equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with eight equivalent Mg(1)Mg3Zn9 cuboctahedra, faces with four equivalent Zn(2)Mg6Zn6 cuboctahedra, faces with eight equivalent Mg(1)Mg3Zn9 cuboctahedra, and faces with eight equivalent Zn(1)Mg4Zn8 cuboctahedra. In the second Zn site, Zn(2) is bonded to six equivalent Mg(1) and six equivalent Zn(1) atoms to form ZnMg6Zn6 cuboctahedra that share corners with eighteen equivalent Mg(1)Mg3Zn9 cuboctahedra, edges with six equivalent Zn(2)Mg6Zn6 cuboctahedra, edges with twelve equivalent Zn(1)Mg4Zn8 cuboctahedra, faces with two equivalent Zn(2)Mg6Zn6 cuboctahedra, faces with six equivalent Mg(1)Mg3Zn9 cuboctahedra, and faces with twelve equivalent Zn(1)Mg4Zn8 cuboctahedra.
MgZn2 crystallizes in the hexagonal P-62m space group. Mg(1) is bonded to three equivalent Mg(1), three equivalent Zn(2), and six equivalent Zn(1) atoms to form MgMg3Zn9 cuboctahedra that share corners with nine equivalent Mg(1)Mg3Zn9 cuboctahedra, corners with nine equivalent Zn(2)Mg6Zn6 cuboctahedra, edges with six equivalent Mg(1)Mg3Zn9 cuboctahedra, edges with twelve equivalent Zn(1)Mg4Zn8 cuboctahedra, faces with three equivalent Zn(2)Mg6Zn6 cuboctahedra, faces with five equivalent Mg(1)Mg3Zn9 cuboctahedra, and faces with twelve equivalent Zn(1)Mg4Zn8 cuboctahedra. All Mg(1)-Mg(1) bond lengths are 2.87 Å. All Mg(1)-Zn(2) bond lengths are 2.87 Å. All Mg(1)-Zn(1) bond lengths are 2.93 Å. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to four equivalent Mg(1), two equivalent Zn(2), and six equivalent Zn(1) atoms to form distorted ZnMg4Zn8 cuboctahedra that share corners with eighteen equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with four equivalent Zn(2)Mg6Zn6 cuboctahedra, edges with six equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with eight equivalent Mg(1)Mg3Zn9 cuboctahedra, faces with four equivalent Zn(2)Mg6Zn6 cuboctahedra, faces with eight equivalent Mg(1)Mg3Zn9 cuboctahedra, and faces with eight equivalent Zn(1)Mg4Zn8 cuboctahedra. Both Zn(1)-Zn(2) bond lengths are 2.87 Å. There are two shorter (2.75 Å) and four longer (2.93 Å) Zn(1)-Zn(1) bond lengths. In the second Zn site, Zn(2) is bonded to six equivalent Mg(1) and six equivalent Zn(1) atoms to form ZnMg6Zn6 cuboctahedra that share corners with eighteen equivalent Mg(1)Mg3Zn9 cuboctahedra, edges with six equivalent Zn(2)Mg6Zn6 cuboctahedra, edges with twelve equivalent Zn(1)Mg4Zn8 cuboctahedra, faces with two equivalent Zn(2)Mg6Zn6 cuboctahedra, faces with six equivalent Mg(1)Mg3Zn9 cuboctahedra, and faces with twelve equivalent Zn(1)Mg4Zn8 cuboctahedra.