TlCu2Se2 crystallizes in the tetragonal I4/mmm space group. Cu(1) is bonded to four equivalent Se(1) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. Tl(1) is bonded in a distorted body-centered cubic geometry to eight equivalent Se(1) atoms. Se(1) is bonded in a 4-coordinate geometry to four equivalent Cu(1) and four equivalent Tl(1) atoms.
TlCu2Se2 crystallizes in the tetragonal I4/mmm space group. Cu(1) is bonded to four equivalent Se(1) atoms to form a mixture of corner and edge-sharing CuSe4 tetrahedra. All Cu(1)-Se(1) bond lengths are 2.45 Å. Tl(1) is bonded in a distorted body-centered cubic geometry to eight equivalent Se(1) atoms. All Tl(1)-Se(1) bond lengths are 3.41 Å. Se(1) is bonded in a 4-coordinate geometry to four equivalent Cu(1) and four equivalent Tl(1) atoms.