CsCu3GeSe4 crystallizes in the cubic P-43m space group. Cs(1) is bonded to four equivalent Se(1) atoms to form CsSe4 tetrahedra that share corners with four equivalent Ge(1)Se4 tetrahedra. Cu(1) is bonded in a 4-coordinate geometry to four equivalent Se(1) atoms. Ge(1) is bonded to four equivalent Se(1) atoms to form GeSe4 tetrahedra that share corners with four equivalent Cs(1)Se4 tetrahedra. Se(1) is bonded to one Cs(1), three equivalent Cu(1), and one Ge(1) atom to form a mixture of corner and edge-sharing SeCsCu3Ge trigonal bipyramids.
CsCu3GeSe4 crystallizes in the cubic P-43m space group. Cs(1) is bonded to four equivalent Se(1) atoms to form CsSe4 tetrahedra that share corners with four equivalent Ge(1)Se4 tetrahedra. All Cs(1)-Se(1) bond lengths are 3.17 Å. Cu(1) is bonded in a 4-coordinate geometry to four equivalent Se(1) atoms. All Cu(1)-Se(1) bond lengths are 2.63 Å. Ge(1) is bonded to four equivalent Se(1) atoms to form GeSe4 tetrahedra that share corners with four equivalent Cs(1)Se4 tetrahedra. All Ge(1)-Se(1) bond lengths are 2.31 Å. Se(1) is bonded to one Cs(1), three equivalent Cu(1), and one Ge(1) atom to form a mixture of corner and edge-sharing SeCsCu3Ge trigonal bipyramids.