K6HgS4 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one S(2) and three equivalent S(1) atoms to form distorted KS4 tetrahedra that share corners with two equivalent Hg(1)K3S4 tetrahedra, corners with eight equivalent K(1)S4 tetrahedra, and  an edgeedge with one Hg(1)K3S4 tetrahedra. In the second K site, K(2) is bonded in a 6-coordinate geometry to one Hg(1), one S(2), and four equivalent S(1) atoms. Hg(1) is bonded to three equivalent K(2), one S(2), and three equivalent S(1) atoms to form distorted HgK3S4 tetrahedra that share corners with six equivalent K(1)S4 tetrahedra and edges with three equivalent K(1)S4 tetrahedra. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 8-coordinate geometry to three equivalent K(1), four equivalent K(2), and one Hg(1) atom. In the second S site, S(2) is bonded in a 7-coordinate geometry to three equivalent K(1), three equivalent K(2), and one Hg(1) atom.
K6HgS4 crystallizes in the hexagonal P6_3mc space group. There are two inequivalent K sites. In the first K site, K(1) is bonded to one S(2) and three equivalent S(1) atoms to form distorted KS4 tetrahedra that share corners with two equivalent Hg(1)K3S4 tetrahedra, corners with eight equivalent K(1)S4 tetrahedra, and  an edgeedge with one Hg(1)K3S4 tetrahedra. The K(1)-S(2) bond length is 3.23 Å. There are two shorter (3.11 Å) and one longer (3.13 Å) K(1)-S(1) bond length. In the second K site, K(2) is bonded in a 6-coordinate geometry to one Hg(1), one S(2), and four equivalent S(1) atoms. The K(2)-Hg(1) bond length is 3.51 Å. The K(2)-S(2) bond length is 3.23 Å. There are two shorter (3.23 Å) and two longer (3.50 Å) K(2)-S(1) bond lengths. Hg(1) is bonded to three equivalent K(2), one S(2), and three equivalent S(1) atoms to form distorted HgK3S4 tetrahedra that share corners with six equivalent K(1)S4 tetrahedra and edges with three equivalent K(1)S4 tetrahedra. The Hg(1)-S(2) bond length is 2.65 Å. All Hg(1)-S(1) bond lengths are 2.61 Å. There are two inequivalent S sites. In the first S site, S(1) is bonded in a 8-coordinate geometry to three equivalent K(1), four equivalent K(2), and one Hg(1) atom. In the second S site, S(2) is bonded in a 7-coordinate geometry to three equivalent K(1), three equivalent K(2), and one Hg(1) atom.