MgZn3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Zn(1) and eight equivalent Zn(2) atoms to form MgZn12 cuboctahedra that share corners with four equivalent Mg(1)Zn12 cuboctahedra, corners with eight equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with eight equivalent Mg(1)Zn12 cuboctahedra, edges with sixteen equivalent Zn(2)Mg4Zn8 cuboctahedra, faces with four equivalent Mg(1)Zn12 cuboctahedra, faces with six equivalent Zn(1)Mg4Zn8 cuboctahedra, and faces with eight equivalent Zn(2)Mg4Zn8 cuboctahedra. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to four equivalent Mg(1) and eight equivalent Zn(2) atoms to form ZnMg4Zn8 cuboctahedra that share corners with four equivalent Zn(1)Mg4Zn8 cuboctahedra, corners with eight equivalent Mg(1)Zn12 cuboctahedra, edges with eight equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with sixteen equivalent Zn(2)Mg4Zn8 cuboctahedra, faces with four equivalent Zn(1)Mg4Zn8 cuboctahedra, faces with six equivalent Mg(1)Zn12 cuboctahedra, and faces with eight equivalent Zn(2)Mg4Zn8 cuboctahedra. In the second Zn site, Zn(2) is bonded to four equivalent Mg(1), four equivalent Zn(1), and four equivalent Zn(2) atoms to form distorted ZnMg4Zn8 cuboctahedra that share corners with twelve equivalent Zn(2)Mg4Zn8 cuboctahedra, edges with eight equivalent Mg(1)Zn12 cuboctahedra, edges with eight equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with eight equivalent Zn(2)Mg4Zn8 cuboctahedra, faces with four equivalent Mg(1)Zn12 cuboctahedra, faces with four equivalent Zn(1)Mg4Zn8 cuboctahedra, and faces with ten equivalent Zn(2)Mg4Zn8 cuboctahedra.
MgZn3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. Mg(1) is bonded to four equivalent Zn(1) and eight equivalent Zn(2) atoms to form MgZn12 cuboctahedra that share corners with four equivalent Mg(1)Zn12 cuboctahedra, corners with eight equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with eight equivalent Mg(1)Zn12 cuboctahedra, edges with sixteen equivalent Zn(2)Mg4Zn8 cuboctahedra, faces with four equivalent Mg(1)Zn12 cuboctahedra, faces with six equivalent Zn(1)Mg4Zn8 cuboctahedra, and faces with eight equivalent Zn(2)Mg4Zn8 cuboctahedra. All Mg(1)-Zn(1) bond lengths are 2.91 Å. All Mg(1)-Zn(2) bond lengths are 2.83 Å. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to four equivalent Mg(1) and eight equivalent Zn(2) atoms to form ZnMg4Zn8 cuboctahedra that share corners with four equivalent Zn(1)Mg4Zn8 cuboctahedra, corners with eight equivalent Mg(1)Zn12 cuboctahedra, edges with eight equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with sixteen equivalent Zn(2)Mg4Zn8 cuboctahedra, faces with four equivalent Zn(1)Mg4Zn8 cuboctahedra, faces with six equivalent Mg(1)Zn12 cuboctahedra, and faces with eight equivalent Zn(2)Mg4Zn8 cuboctahedra. All Zn(1)-Zn(2) bond lengths are 2.83 Å. In the second Zn site, Zn(2) is bonded to four equivalent Mg(1), four equivalent Zn(1), and four equivalent Zn(2) atoms to form distorted ZnMg4Zn8 cuboctahedra that share corners with twelve equivalent Zn(2)Mg4Zn8 cuboctahedra, edges with eight equivalent Mg(1)Zn12 cuboctahedra, edges with eight equivalent Zn(1)Mg4Zn8 cuboctahedra, edges with eight equivalent Zn(2)Mg4Zn8 cuboctahedra, faces with four equivalent Mg(1)Zn12 cuboctahedra, faces with four equivalent Zn(1)Mg4Zn8 cuboctahedra, and faces with ten equivalent Zn(2)Mg4Zn8 cuboctahedra. All Zn(2)-Zn(2) bond lengths are 2.91 Å.