Mg(AlSn)2 crystallizes in the trigonal P-3m1 space group. Mg(1) is bonded to six equivalent Sn(1) atoms to form MgSn6 octahedra that share corners with twelve equivalent Al(1)Sn4 tetrahedra, edges with six equivalent Mg(1)Sn6 octahedra, and edges with six equivalent Al(1)Sn4 tetrahedra. Al(1) is bonded to four equivalent Sn(1) atoms to form AlSn4 tetrahedra that share corners with six equivalent Mg(1)Sn6 octahedra, corners with six equivalent Al(1)Sn4 tetrahedra, edges with three equivalent Mg(1)Sn6 octahedra, and edges with three equivalent Al(1)Sn4 tetrahedra. The corner-sharing octahedral tilt angles range from 11-57°. Sn(1) is bonded to three equivalent Mg(1) and four equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing SnMg3Al4 pentagonal bipyramids.
Mg(AlSn)2 crystallizes in the trigonal P-3m1 space group. Mg(1) is bonded to six equivalent Sn(1) atoms to form MgSn6 octahedra that share corners with twelve equivalent Al(1)Sn4 tetrahedra, edges with six equivalent Mg(1)Sn6 octahedra, and edges with six equivalent Al(1)Sn4 tetrahedra. All Mg(1)-Sn(1) bond lengths are 3.08 Å. Al(1) is bonded to four equivalent Sn(1) atoms to form AlSn4 tetrahedra that share corners with six equivalent Mg(1)Sn6 octahedra, corners with six equivalent Al(1)Sn4 tetrahedra, edges with three equivalent Mg(1)Sn6 octahedra, and edges with three equivalent Al(1)Sn4 tetrahedra. The corner-sharing octahedral tilt angles range from 11-57°. There are three shorter (2.78 Å) and one longer (2.85 Å) Al(1)-Sn(1) bond length. Sn(1) is bonded to three equivalent Mg(1) and four equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing SnMg3Al4 pentagonal bipyramids.