K2Th(CuS2)2 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 7-coordinate geometry to three equivalent S(2) and four equivalent S(1) atoms. Th(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form ThS6 octahedra that share corners with two equivalent Cu(1)S4 tetrahedra, edges with two equivalent Th(1)S6 octahedra, and edges with four equivalent Cu(1)S4 tetrahedra. Cu(1) is bonded to one S(1) and three equivalent S(2) atoms to form CuS4 tetrahedra that share  a cornercorner with one Th(1)S6 octahedra, corners with two equivalent Cu(1)S4 tetrahedra, edges with two equivalent Th(1)S6 octahedra, and edges with two equivalent Cu(1)S4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 7-coordinate geometry to four equivalent K(1), two equivalent Th(1), and one Cu(1) atom. In the second S site, S(2) is bonded in a 7-coordinate geometry to three equivalent K(1), one Th(1), and three equivalent Cu(1) atoms.
K2Th(CuS2)2 crystallizes in the monoclinic C2/m space group. K(1) is bonded in a 7-coordinate geometry to three equivalent S(2) and four equivalent S(1) atoms. There are two shorter (3.20 Å) and one longer (3.42 Å) K(1)-S(2) bond length. There are two shorter (3.29 Å) and two longer (3.43 Å) K(1)-S(1) bond lengths. Th(1) is bonded to two equivalent S(2) and four equivalent S(1) atoms to form ThS6 octahedra that share corners with two equivalent Cu(1)S4 tetrahedra, edges with two equivalent Th(1)S6 octahedra, and edges with four equivalent Cu(1)S4 tetrahedra. Both Th(1)-S(2) bond lengths are 2.78 Å. All Th(1)-S(1) bond lengths are 2.80 Å. Cu(1) is bonded to one S(1) and three equivalent S(2) atoms to form CuS4 tetrahedra that share  a cornercorner with one Th(1)S6 octahedra, corners with two equivalent Cu(1)S4 tetrahedra, edges with two equivalent Th(1)S6 octahedra, and edges with two equivalent Cu(1)S4 tetrahedra. The corner-sharing octahedral tilt angles are 55°. The Cu(1)-S(1) bond length is 2.36 Å. All Cu(1)-S(2) bond lengths are 2.42 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 7-coordinate geometry to four equivalent K(1), two equivalent Th(1), and one Cu(1) atom. In the second S site, S(2) is bonded in a 7-coordinate geometry to three equivalent K(1), one Th(1), and three equivalent Cu(1) atoms.