Ba2Cu2TlAlO7 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(2) atoms. Cu(1) is bonded in a square co-planar geometry to four equivalent O(2) atoms. Tl(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form a mixture of corner and edge-sharing TlO6 octahedra. The corner-sharing octahedra are not tilted. Al(1) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one Tl(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Cu(1), and two equivalent Al(1) atoms. In the third O site, O(3) is bonded to two equivalent Ba(1) and four equivalent Tl(1) atoms to form a mixture of corner and edge-sharing OBa2Tl4 octahedra. The corner-sharing octahedra are not tilted.
Ba2Cu2TlAlO7 crystallizes in the tetragonal P4/mmm space group. Ba(1) is bonded in a 9-coordinate geometry to one O(3), four equivalent O(1), and four equivalent O(2) atoms. The Ba(1)-O(3) bond length is 2.75 Å. All Ba(1)-O(1) bond lengths are 2.73 Å. All Ba(1)-O(2) bond lengths are 3.10 Å. Cu(1) is bonded in a square co-planar geometry to four equivalent O(2) atoms. All Cu(1)-O(2) bond lengths are 1.89 Å. Tl(1) is bonded to two equivalent O(1) and four equivalent O(3) atoms to form a mixture of corner and edge-sharing TlO6 octahedra. The corner-sharing octahedra are not tilted. Both Tl(1)-O(1) bond lengths are 2.12 Å. All Tl(1)-O(3) bond lengths are 2.65 Å. Al(1) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. All Al(1)-O(2) bond lengths are 2.25 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded in a 5-coordinate geometry to four equivalent Ba(1) and one Tl(1) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Cu(1), and two equivalent Al(1) atoms. In the third O site, O(3) is bonded to two equivalent Ba(1) and four equivalent Tl(1) atoms to form a mixture of corner and edge-sharing OBa2Tl4 octahedra. The corner-sharing octahedra are not tilted.