Ba3(AlSn)2 crystallizes in the orthorhombic Immm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to eight equivalent Al(1) and four equivalent Sn(1) atoms to form a mixture of edge and face-sharing BaAl8Sn4 cuboctahedra. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to two equivalent Al(1) and five equivalent Sn(1) atoms. Al(1) is bonded in a 9-coordinate geometry to two equivalent Ba(2), four equivalent Ba(1), one Al(1), and two equivalent Sn(1) atoms. Sn(1) is bonded in a 9-coordinate geometry to two equivalent Ba(1), five equivalent Ba(2), and two equivalent Al(1) atoms.
Ba3(AlSn)2 crystallizes in the orthorhombic Immm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded to eight equivalent Al(1) and four equivalent Sn(1) atoms to form a mixture of edge and face-sharing BaAl8Sn4 cuboctahedra. All Ba(1)-Al(1) bond lengths are 3.74 Å. All Ba(1)-Sn(1) bond lengths are 3.86 Å. In the second Ba site, Ba(2) is bonded in a 7-coordinate geometry to two equivalent Al(1) and five equivalent Sn(1) atoms. Both Ba(2)-Al(1) bond lengths are 3.64 Å. There are four shorter (3.65 Å) and one longer (3.78 Å) Ba(2)-Sn(1) bond length. Al(1) is bonded in a 9-coordinate geometry to two equivalent Ba(2), four equivalent Ba(1), one Al(1), and two equivalent Sn(1) atoms. The Al(1)-Al(1) bond length is 2.56 Å. Both Al(1)-Sn(1) bond lengths are 2.77 Å. Sn(1) is bonded in a 9-coordinate geometry to two equivalent Ba(1), five equivalent Ba(2), and two equivalent Al(1) atoms.