The crystal structure described by Pb3Bi2S6 crystallizes in the monoclinic C2/m space group. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one S(1), one S(7), two equivalent S(3), and two equivalent S(4) atoms to form PbS6 octahedra that share  a cornercorner with one Pb(1)S6 octahedra,  a cornercorner with one Bi(1)S6 octahedra, corners with two equivalent Bi(2)S6 octahedra, edges with two equivalent Pb(1)S6 octahedra, and edges with five equivalent Bi(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-56°. In the second Pb site, Pb(2) is bonded to one S(6), two equivalent S(2), and two equivalent S(5) atoms to form PbS5 square pyramids that share corners with four equivalent Bi(1)S6 octahedra, corners with two equivalent Pb(2)S5 square pyramids, edges with three equivalent Bi(1)S6 octahedra, and edges with three equivalent Pb(2)S5 square pyramids. The corner-sharing octahedral tilt angles range from 10-87°. In the third Pb site, Pb(3) is bonded in a 3-coordinate geometry to one S(2) and two equivalent S(1) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one S(1), one S(5), two equivalent S(2), and two equivalent S(6) atoms to form BiS6 octahedra that share  a cornercorner with one Pb(1)S6 octahedra,  a cornercorner with one Bi(1)S6 octahedra, corners with four equivalent Pb(2)S5 square pyramids, edges with two equivalent Bi(1)S6 octahedra, and edges with three equivalent Pb(2)S5 square pyramids. The corner-sharing octahedral tilt angles range from 0-56°. In the second Bi site, Bi(2) is bonded to one S(4), two equivalent S(7), and three equivalent S(3) atoms to form BiS6 octahedra that share corners with two equivalent Pb(1)S6 octahedra, corners with two equivalent Bi(2)S6 octahedra, edges with five equivalent Pb(1)S6 octahedra, and edges with five equivalent Bi(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Pb(1), two equivalent Pb(3), and one Bi(1) atom. In the second S site, S(2) is bonded to one Pb(3), two equivalent Pb(2), and two equivalent Bi(1) atoms to form SBi2Pb3 square pyramids that share corners with four equivalent S(5)Bi2Pb4 octahedra,  an edgeedge with one S(5)Bi2Pb4 octahedra, and edges with two equivalent S(2)Bi2Pb3 square pyramids. The corner-sharing octahedral tilt angles range from 4-88°. In the third S site, S(3) is bonded to two equivalent Pb(1) and three equivalent Bi(2) atoms to form SBi3Pb2 square pyramids that share corners with two equivalent S(7)Bi4Pb2 octahedra, edges with three equivalent S(7)Bi4Pb2 octahedra, and edges with four equivalent S(3)Bi3Pb2 square pyramids. The corner-sharing octahedral tilt angles are 7°. In the fourth S site, S(4) is bonded in a 3-coordinate geometry to two equivalent Pb(1) and one Bi(2) atom. In the fifth S site, S(5) is bonded to four equivalent Pb(2) and two equivalent Bi(1) atoms to form SBi2Pb4 octahedra that share corners with eight equivalent S(2)Bi2Pb3 square pyramids, edges with two equivalent S(5)Bi2Pb4 octahedra, and edges with two equivalent S(2)Bi2Pb3 square pyramids. In the sixth S site, S(6) is bonded in a 3-coordinate geometry to one Pb(2) and two equivalent Bi(1) atoms. In the seventh S site, S(7) is bonded to two equivalent Pb(1) and four equivalent Bi(2) atoms to form SBi4Pb2 octahedra that share corners with four equivalent S(3)Bi3Pb2 square pyramids, edges with two equivalent S(7)Bi4Pb2 octahedra, and edges with six equivalent S(3)Bi3Pb2 square pyramids. is represented by the CIF file [CIF]
data_Bi2(PbS2)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.109
_cell_length_b   7.109
_cell_length_c   21.116
_cell_angle_alpha   87.381
_cell_angle_beta   87.381
_cell_angle_gamma   33.479
_symmetry_Int_Tables_number   1
_cell_volume   588.058
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Bi  Bi0  1  0.403  0.403  0.135  1.0
  Bi  Bi1  1  0.859  0.859  0.549  1.0
  Bi  Bi2  1  0.141  0.141  0.451  1.0
  Bi  Bi3  1  0.597  0.597  0.865  1.0
  Pb  Pb4  1  0.577  0.577  0.635  1.0
  Pb  Pb5  1  0.423  0.423  0.365  1.0
  Pb  Pb6  1  0.866  0.866  0.954  1.0
  Pb  Pb7  1  0.676  0.676  0.235  1.0
  Pb  Pb8  1  0.134  0.134  0.046  1.0
  Pb  Pb9  1  0.324  0.324  0.765  1.0
  S  S10  1  0.317  0.317  0.250  1.0
  S  S11  1  0.765  0.765  0.103  1.0
  S  S12  1  0.769  0.769  0.419  1.0
  S  S13  1  0.936  0.936  0.663  1.0
  S  S14  1  0.683  0.683  0.750  1.0
  S  S15  1  0.231  0.231  0.581  1.0
  S  S16  1  0.500  0.500  0.000  1.0
  S  S17  1  0.235  0.235  0.897  1.0
  S  S18  1  0.064  0.064  0.337  1.0
  S  S19  1  0.034  0.034  0.163  1.0
  S  S20  1  0.500  0.500  0.500  1.0
  S  S21  1  0.966  0.966  0.837  1.0
[/CIF]
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The crystal structure described by Pb3Bi2S6 crystallizes in the monoclinic C2/m space group. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one S(1), one S(7), two equivalent S(3), and two equivalent S(4) atoms to form PbS6 octahedra that share  a cornercorner with one Pb(1)S6 octahedra,  a cornercorner with one Bi(1)S6 octahedra, corners with two equivalent Bi(2)S6 octahedra, edges with two equivalent Pb(1)S6 octahedra, and edges with five equivalent Bi(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-56°. In the second Pb site, Pb(2) is bonded to one S(6), two equivalent S(2), and two equivalent S(5) atoms to form PbS5 square pyramids that share corners with four equivalent Bi(1)S6 octahedra, corners with two equivalent Pb(2)S5 square pyramids, edges with three equivalent Bi(1)S6 octahedra, and edges with three equivalent Pb(2)S5 square pyramids. The corner-sharing octahedral tilt angles range from 10-87°. In the third Pb site, Pb(3) is bonded in a 3-coordinate geometry to one S(2) and two equivalent S(1) atoms. There are two inequivalent Bi sites. In the first Bi site, Bi(1) is bonded to one S(1), one S(5), two equivalent S(2), and two equivalent S(6) atoms to form BiS6 octahedra that share  a cornercorner with one Pb(1)S6 octahedra,  a cornercorner with one Bi(1)S6 octahedra, corners with four equivalent Pb(2)S5 square pyramids, edges with two equivalent Bi(1)S6 octahedra, and edges with three equivalent Pb(2)S5 square pyramids. The corner-sharing octahedral tilt angles range from 0-56°. In the second Bi site, Bi(2) is bonded to one S(4), two equivalent S(7), and three equivalent S(3) atoms to form BiS6 octahedra that share corners with two equivalent Pb(1)S6 octahedra, corners with two equivalent Bi(2)S6 octahedra, edges with five equivalent Pb(1)S6 octahedra, and edges with five equivalent Bi(2)S6 octahedra. The corner-sharing octahedral tilt angles range from 0-9°. There are seven inequivalent S sites. In the first S site, S(1) is bonded in a distorted rectangular see-saw-like geometry to one Pb(1), two equivalent Pb(3), and one Bi(1) atom. In the second S site, S(2) is bonded to one Pb(3), two equivalent Pb(2), and two equivalent Bi(1) atoms to form SBi2Pb3 square pyramids that share corners with four equivalent S(5)Bi2Pb4 octahedra,  an edgeedge with one S(5)Bi2Pb4 octahedra, and edges with two equivalent S(2)Bi2Pb3 square pyramids. The corner-sharing octahedral tilt angles range from 4-88°. In the third S site, S(3) is bonded to two equivalent Pb(1) and three equivalent Bi(2) atoms to form SBi3Pb2 square pyramids that share corners with two equivalent S(7)Bi4Pb2 octahedra, edges with three equivalent S(7)Bi4Pb2 octahedra, and edges with four equivalent S(3)Bi3Pb2 square pyramids. The corner-sharing octahedral tilt angles are 7°. In the fourth S site, S(4) is bonded in a 3-coordinate geometry to two equivalent Pb(1) and one Bi(2) atom. In the fifth S site, S(5) is bonded to four equivalent Pb(2) and two equivalent Bi(1) atoms to form SBi2Pb4 octahedra that share corners with eight equivalent S(2)Bi2Pb3 square pyramids, edges with two equivalent S(5)Bi2Pb4 octahedra, and edges with two equivalent S(2)Bi2Pb3 square pyramids. In the sixth S site, S(6) is bonded in a 3-coordinate geometry to one Pb(2) and two equivalent Bi(1) atoms. In the seventh S site, S(7) is bonded to two equivalent Pb(1) and four equivalent Bi(2) atoms to form SBi4Pb2 octahedra that share corners with four equivalent S(3)Bi3Pb2 square pyramids, edges with two equivalent S(7)Bi4Pb2 octahedra, and edges with six equivalent S(3)Bi3Pb2 square pyramids. is represented by the CIF file [CIF]
data_Bi2(PbS2)3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.109
_cell_length_b   7.109
_cell_length_c   21.116
_cell_angle_alpha   87.381
_cell_angle_beta   87.381
_cell_angle_gamma   33.479
_symmetry_Int_Tables_number   1
_cell_volume   588.058
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
loop_
 _atom_site_type_symbol
 _atom_site_label
 _atom_site_symmetry_multiplicity
 _atom_site_fract_x
 _atom_site_fract_y
 _atom_site_fract_z
 _atom_site_occupancy
  Bi  Bi0  1  0.403  0.403  0.135  1.0
  Bi  Bi1  1  0.859  0.859  0.549  1.0
  Bi  Bi2  1  0.141  0.141  0.451  1.0
  Bi  Bi3  1  0.597  0.597  0.865  1.0
  Pb  Pb4  1  0.577  0.577  0.635  1.0
  Pb  Pb5  1  0.423  0.423  0.365  1.0
  Pb  Pb6  1  0.866  0.866  0.954  1.0
  Pb  Pb7  1  0.676  0.676  0.235  1.0
  Pb  Pb8  1  0.134  0.134  0.046  1.0
  Pb  Pb9  1  0.324  0.324  0.765  1.0
  S  S10  1  0.317  0.317  0.250  1.0
  S  S11  1  0.765  0.765  0.103  1.0
  S  S12  1  0.769  0.769  0.419  1.0
  S  S13  1  0.936  0.936  0.663  1.0
  S  S14  1  0.683  0.683  0.750  1.0
  S  S15  1  0.231  0.231  0.581  1.0
  S  S16  1  0.500  0.500  0.000  1.0
  S  S17  1  0.235  0.235  0.897  1.0
  S  S18  1  0.064  0.064  0.337  1.0
  S  S19  1  0.034  0.034  0.163  1.0
  S  S20  1  0.500  0.500  0.500  1.0
  S  S21  1  0.966  0.966  0.837  1.0
[/CIF]
.