Cs2Ti(CuSe2)2 crystallizes in the tetragonal P4_2/mcm space group. Cs(1) is bonded in a body-centered cubic geometry to eight equivalent Se(1) atoms. Ti(1) is bonded to four equivalent Se(1) atoms to form TiSe4 tetrahedra that share edges with four equivalent Cu(1)Se4 tetrahedra. Cu(1) is bonded to four equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra and edges with two equivalent Ti(1)Se4 tetrahedra. Se(1) is bonded in a 7-coordinate geometry to four equivalent Cs(1), one Ti(1), and two equivalent Cu(1) atoms.
Cs2Ti(CuSe2)2 crystallizes in the tetragonal P4_2/mcm space group. Cs(1) is bonded in a body-centered cubic geometry to eight equivalent Se(1) atoms. There are four shorter (3.72 Å) and four longer (3.75 Å) Cs(1)-Se(1) bond lengths. Ti(1) is bonded to four equivalent Se(1) atoms to form TiSe4 tetrahedra that share edges with four equivalent Cu(1)Se4 tetrahedra. All Ti(1)-Se(1) bond lengths are 2.42 Å. Cu(1) is bonded to four equivalent Se(1) atoms to form distorted CuSe4 tetrahedra that share corners with four equivalent Cu(1)Se4 tetrahedra and edges with two equivalent Ti(1)Se4 tetrahedra. All Cu(1)-Se(1) bond lengths are 2.49 Å. Se(1) is bonded in a 7-coordinate geometry to four equivalent Cs(1), one Ti(1), and two equivalent Cu(1) atoms.