Al3Sn is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Al(1), four equivalent Al(2), and four equivalent Sn(1) atoms to form distorted AlAl8Sn4 cuboctahedra that share corners with twelve equivalent Al(1)Al8Sn4 cuboctahedra, edges with eight equivalent Al(1)Al8Sn4 cuboctahedra, edges with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with eight equivalent Sn(1)Al12 cuboctahedra, faces with four equivalent Al(2)Al8Sn4 cuboctahedra, faces with four equivalent Sn(1)Al12 cuboctahedra, and faces with ten equivalent Al(1)Al8Sn4 cuboctahedra. In the second Al site, Al(2) is bonded to eight equivalent Al(1) and four equivalent Sn(1) atoms to form AlAl8Sn4 cuboctahedra that share corners with four equivalent Al(2)Al8Sn4 cuboctahedra, corners with eight equivalent Sn(1)Al12 cuboctahedra, edges with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with sixteen equivalent Al(1)Al8Sn4 cuboctahedra, faces with four equivalent Al(2)Al8Sn4 cuboctahedra, faces with six equivalent Sn(1)Al12 cuboctahedra, and faces with eight equivalent Al(1)Al8Sn4 cuboctahedra. Sn(1) is bonded to four equivalent Al(2) and eight equivalent Al(1) atoms to form SnAl12 cuboctahedra that share corners with four equivalent Sn(1)Al12 cuboctahedra, corners with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with eight equivalent Sn(1)Al12 cuboctahedra, edges with sixteen equivalent Al(1)Al8Sn4 cuboctahedra, faces with four equivalent Sn(1)Al12 cuboctahedra, faces with six equivalent Al(2)Al8Sn4 cuboctahedra, and faces with eight equivalent Al(1)Al8Sn4 cuboctahedra.
Al3Sn is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to four equivalent Al(1), four equivalent Al(2), and four equivalent Sn(1) atoms to form distorted AlAl8Sn4 cuboctahedra that share corners with twelve equivalent Al(1)Al8Sn4 cuboctahedra, edges with eight equivalent Al(1)Al8Sn4 cuboctahedra, edges with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with eight equivalent Sn(1)Al12 cuboctahedra, faces with four equivalent Al(2)Al8Sn4 cuboctahedra, faces with four equivalent Sn(1)Al12 cuboctahedra, and faces with ten equivalent Al(1)Al8Sn4 cuboctahedra. All Al(1)-Al(1) bond lengths are 3.06 Å. All Al(1)-Al(2) bond lengths are 3.01 Å. All Al(1)-Sn(1) bond lengths are 3.01 Å. In the second Al site, Al(2) is bonded to eight equivalent Al(1) and four equivalent Sn(1) atoms to form AlAl8Sn4 cuboctahedra that share corners with four equivalent Al(2)Al8Sn4 cuboctahedra, corners with eight equivalent Sn(1)Al12 cuboctahedra, edges with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with sixteen equivalent Al(1)Al8Sn4 cuboctahedra, faces with four equivalent Al(2)Al8Sn4 cuboctahedra, faces with six equivalent Sn(1)Al12 cuboctahedra, and faces with eight equivalent Al(1)Al8Sn4 cuboctahedra. All Al(2)-Sn(1) bond lengths are 3.06 Å. Sn(1) is bonded to four equivalent Al(2) and eight equivalent Al(1) atoms to form SnAl12 cuboctahedra that share corners with four equivalent Sn(1)Al12 cuboctahedra, corners with eight equivalent Al(2)Al8Sn4 cuboctahedra, edges with eight equivalent Sn(1)Al12 cuboctahedra, edges with sixteen equivalent Al(1)Al8Sn4 cuboctahedra, faces with four equivalent Sn(1)Al12 cuboctahedra, faces with six equivalent Al(2)Al8Sn4 cuboctahedra, and faces with eight equivalent Al(1)Al8Sn4 cuboctahedra.