MgIn5 crystallizes in the hexagonal P-6m2 space group. Mg(1) is bonded to six equivalent In(1) atoms to form distorted MgIn6 cuboctahedra that share corners with twelve equivalent In(2)In12 cuboctahedra, edges with six equivalent Mg(1)In6 cuboctahedra, and faces with two equivalent In(2)In12 cuboctahedra. There are three inequivalent In sites. In the first In site, In(1) is bonded to three equivalent Mg(1) and three equivalent In(2) atoms to form distorted InMg3In3 cuboctahedra that share corners with six equivalent In(2)In12 cuboctahedra, corners with six equivalent In(3)In12 cuboctahedra, corners with six equivalent In(1)Mg3In3 cuboctahedra, edges with six equivalent In(2)In12 cuboctahedra, edges with six equivalent In(1)Mg3In3 cuboctahedra,  a faceface with one In(3)In12 cuboctahedra, and  a faceface with one In(1)Mg3In3 cuboctahedra. In the second In site, In(2) is bonded to three equivalent In(1), three equivalent In(3), and six equivalent In(2) atoms to form InIn12 cuboctahedra that share corners with six equivalent Mg(1)In6 cuboctahedra, corners with six equivalent In(1)Mg3In3 cuboctahedra, corners with twelve equivalent In(2)In12 cuboctahedra, edges with six equivalent In(2)In12 cuboctahedra, edges with six equivalent In(3)In12 cuboctahedra, edges with six equivalent In(1)Mg3In3 cuboctahedra,  a faceface with one Mg(1)In6 cuboctahedra, faces with six equivalent In(3)In12 cuboctahedra, and faces with seven equivalent In(2)In12 cuboctahedra. In the third In site, In(3) is bonded to six equivalent In(2) and six equivalent In(3) atoms to form InIn12 cuboctahedra that share corners with six equivalent In(3)In12 cuboctahedra, corners with twelve equivalent In(1)Mg3In3 cuboctahedra, edges with six equivalent In(3)In12 cuboctahedra, edges with twelve equivalent In(2)In12 cuboctahedra, faces with two equivalent In(1)Mg3In3 cuboctahedra, faces with six equivalent In(3)In12 cuboctahedra, and faces with twelve equivalent In(2)In12 cuboctahedra.
MgIn5 crystallizes in the hexagonal P-6m2 space group. Mg(1) is bonded to six equivalent In(1) atoms to form distorted MgIn6 cuboctahedra that share corners with twelve equivalent In(2)In12 cuboctahedra, edges with six equivalent Mg(1)In6 cuboctahedra, and faces with two equivalent In(2)In12 cuboctahedra. All Mg(1)-In(1) bond lengths are 3.15 Å. There are three inequivalent In sites. In the first In site, In(1) is bonded to three equivalent Mg(1) and three equivalent In(2) atoms to form distorted InMg3In3 cuboctahedra that share corners with six equivalent In(2)In12 cuboctahedra, corners with six equivalent In(3)In12 cuboctahedra, corners with six equivalent In(1)Mg3In3 cuboctahedra, edges with six equivalent In(2)In12 cuboctahedra, edges with six equivalent In(1)Mg3In3 cuboctahedra,  a faceface with one In(3)In12 cuboctahedra, and  a faceface with one In(1)Mg3In3 cuboctahedra. All In(1)-In(2) bond lengths are 3.31 Å. In the second In site, In(2) is bonded to three equivalent In(1), three equivalent In(3), and six equivalent In(2) atoms to form InIn12 cuboctahedra that share corners with six equivalent Mg(1)In6 cuboctahedra, corners with six equivalent In(1)Mg3In3 cuboctahedra, corners with twelve equivalent In(2)In12 cuboctahedra, edges with six equivalent In(2)In12 cuboctahedra, edges with six equivalent In(3)In12 cuboctahedra, edges with six equivalent In(1)Mg3In3 cuboctahedra,  a faceface with one Mg(1)In6 cuboctahedra, faces with six equivalent In(3)In12 cuboctahedra, and faces with seven equivalent In(2)In12 cuboctahedra. All In(2)-In(3) bond lengths are 3.44 Å. All In(2)-In(2) bond lengths are 3.30 Å. In the third In site, In(3) is bonded to six equivalent In(2) and six equivalent In(3) atoms to form InIn12 cuboctahedra that share corners with six equivalent In(3)In12 cuboctahedra, corners with twelve equivalent In(1)Mg3In3 cuboctahedra, edges with six equivalent In(3)In12 cuboctahedra, edges with twelve equivalent In(2)In12 cuboctahedra, faces with two equivalent In(1)Mg3In3 cuboctahedra, faces with six equivalent In(3)In12 cuboctahedra, and faces with twelve equivalent In(2)In12 cuboctahedra. All In(3)-In(3) bond lengths are 3.30 Å.