HgBi2S4 crystallizes in the triclinic P-1 space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a linear geometry to two equivalent S(1) atoms. In the second Hg site, Hg(2) is bonded in a linear geometry to two equivalent S(3) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to two equivalent S(1) and three equivalent S(2) atoms to form BiS5 square pyramids that share corners with two equivalent Bi(2)S6 octahedra and edges with four equivalent Bi(1)S5 square pyramids. The corner-sharing octahedral tilt angles are 59°. In the second Bi site, Bi(2) is bonded to one S(1), two equivalent S(3), and three equivalent S(4) atoms to form BiS6 octahedra that share corners with two equivalent Bi(1)S5 square pyramids and edges with four equivalent Bi(2)S6 octahedra. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Hg(1), one Bi(2), and two equivalent Bi(1) atoms to form distorted corner-sharing SHgBi3 tetrahedra. In the second S site, S(2) is bonded in a 3-coordinate geometry to three equivalent Bi(1) atoms. In the third S site, S(3) is bonded in a 3-coordinate geometry to one Hg(2) and two equivalent Bi(2) atoms. In the fourth S site, S(4) is bonded in a distorted T-shaped geometry to three equivalent Bi(2) atoms.
HgBi2S4 crystallizes in the triclinic P-1 space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a linear geometry to two equivalent S(1) atoms. Both Hg(1)-S(1) bond lengths are 2.38 Å. In the second Hg site, Hg(2) is bonded in a linear geometry to two equivalent S(3) atoms. Both Hg(2)-S(3) bond lengths are 2.37 Å. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to two equivalent S(1) and three equivalent S(2) atoms to form BiS5 square pyramids that share corners with two equivalent Bi(2)S6 octahedra and edges with four equivalent Bi(1)S5 square pyramids. The corner-sharing octahedral tilt angles are 59°. Both Bi(1)-S(1) bond lengths are 2.85 Å. There is one shorter (2.60 Å) and two longer (2.84 Å) Bi(1)-S(2) bond lengths. In the second Bi site, Bi(2) is bonded to one S(1), two equivalent S(3), and three equivalent S(4) atoms to form BiS6 octahedra that share corners with two equivalent Bi(1)S5 square pyramids and edges with four equivalent Bi(2)S6 octahedra. The Bi(2)-S(1) bond length is 3.12 Å. Both Bi(2)-S(3) bond lengths are 2.89 Å. There is one shorter (2.64 Å) and two longer (2.80 Å) Bi(2)-S(4) bond lengths. There are four inequivalent S sites. In the first S site, S(1) is bonded to one Hg(1), one Bi(2), and two equivalent Bi(1) atoms to form distorted corner-sharing SHgBi3 tetrahedra. In the second S site, S(2) is bonded in a 3-coordinate geometry to three equivalent Bi(1) atoms. In the third S site, S(3) is bonded in a 3-coordinate geometry to one Hg(2) and two equivalent Bi(2) atoms. In the fourth S site, S(4) is bonded in a distorted T-shaped geometry to three equivalent Bi(2) atoms.