K3TeS4 crystallizes in the cubic I-43m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to two equivalent S(2) and four equivalent S(3) atoms to form a mixture of edge and corner-sharing KS6 octahedra. The corner-sharing octahedral tilt angles range from 0-21°. In the second K site, K(2) is bonded to one S(1), one S(2), and four equivalent S(3) atoms to form a mixture of edge and corner-sharing KS6 octahedra. The corner-sharing octahedral tilt angles range from 0-21°. Te(1) is bonded in a trigonal non-coplanar geometry to three equivalent S(3) atoms. There are three inequivalent S sites. In the first S site, S(1) is bonded to six equivalent K(2) atoms to form SK6 octahedra that share corners with six equivalent S(2)K6 octahedra and edges with twelve equivalent S(3)K4Te trigonal bipyramids. The corner-sharing octahedra are not tilted. In the second S site, S(2) is bonded to two equivalent K(2) and four equivalent K(1) atoms to form SK6 octahedra that share corners with two equivalent S(1)K6 octahedra, corners with four equivalent S(2)K6 octahedra, and edges with twelve equivalent S(3)K4Te trigonal bipyramids. The corner-sharing octahedra are not tilted. In the third S site, S(3) is bonded to two equivalent K(1), two equivalent K(2), and one Te(1) atom to form SK4Te trigonal bipyramids that share corners with ten equivalent S(3)K4Te trigonal bipyramids,  an edgeedge with one S(1)K6 octahedra, edges with three equivalent S(2)K6 octahedra, and edges with two equivalent S(3)K4Te trigonal bipyramids.
K3TeS4 crystallizes in the cubic I-43m space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to two equivalent S(2) and four equivalent S(3) atoms to form a mixture of edge and corner-sharing KS6 octahedra. The corner-sharing octahedral tilt angles range from 0-21°. Both K(1)-S(2) bond lengths are 3.25 Å. All K(1)-S(3) bond lengths are 3.31 Å. In the second K site, K(2) is bonded to one S(1), one S(2), and four equivalent S(3) atoms to form a mixture of edge and corner-sharing KS6 octahedra. The corner-sharing octahedral tilt angles range from 0-21°. The K(2)-S(1) bond length is 3.26 Å. The K(2)-S(2) bond length is 3.24 Å. All K(2)-S(3) bond lengths are 3.31 Å. Te(1) is bonded in a trigonal non-coplanar geometry to three equivalent S(3) atoms. All Te(1)-S(3) bond lengths are 2.37 Å. There are three inequivalent S sites. In the first S site, S(1) is bonded to six equivalent K(2) atoms to form SK6 octahedra that share corners with six equivalent S(2)K6 octahedra and edges with twelve equivalent S(3)K4Te trigonal bipyramids. The corner-sharing octahedra are not tilted. In the second S site, S(2) is bonded to two equivalent K(2) and four equivalent K(1) atoms to form SK6 octahedra that share corners with two equivalent S(1)K6 octahedra, corners with four equivalent S(2)K6 octahedra, and edges with twelve equivalent S(3)K4Te trigonal bipyramids. The corner-sharing octahedra are not tilted. In the third S site, S(3) is bonded to two equivalent K(1), two equivalent K(2), and one Te(1) atom to form SK4Te trigonal bipyramids that share corners with ten equivalent S(3)K4Te trigonal bipyramids,  an edgeedge with one S(1)K6 octahedra, edges with three equivalent S(2)K6 octahedra, and edges with two equivalent S(3)K4Te trigonal bipyramids.