The crystal structure described by Pb4Se3S is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Se(2), four equivalent Se(1), and one S(1) atom to form PbSe5S octahedra that share corners with six equivalent Pb(1)Se5S octahedra, edges with four equivalent Pb(3)Se2S4 octahedra, edges with four equivalent Pb(1)Se5S octahedra, and edges with four equivalent Pb(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Pb site, Pb(2) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form PbSe6 octahedra that share corners with two equivalent Pb(3)Se2S4 octahedra, corners with four equivalent Pb(2)Se6 octahedra, edges with four equivalent Pb(2)Se6 octahedra, and edges with eight equivalent Pb(1)Se5S octahedra. The corner-sharing octahedra are not tilted. In the third Pb site, Pb(3) is bonded to two equivalent Se(1) and four equivalent S(1) atoms to form PbSe2S4 octahedra that share corners with two equivalent Pb(2)Se6 octahedra, corners with four equivalent Pb(3)Se2S4 octahedra, edges with four equivalent Pb(3)Se2S4 octahedra, and edges with eight equivalent Pb(1)Se5S octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Pb(2), one Pb(3), and four equivalent Pb(1) atoms to form SePb6 octahedra that share corners with six equivalent Se(1)Pb6 octahedra, edges with four equivalent Se(1)Pb6 octahedra, edges with four equivalent Se(2)Pb6 octahedra, and edges with four equivalent S(1)Pb6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Se site, Se(2) is bonded to two equivalent Pb(1) and four equivalent Pb(2) atoms to form SePb6 octahedra that share corners with two equivalent S(1)Pb6 octahedra, corners with four equivalent Se(2)Pb6 octahedra, edges with four equivalent Se(2)Pb6 octahedra, and edges with eight equivalent Se(1)Pb6 octahedra. The corner-sharing octahedra are not tilted. S(1) is bonded to two equivalent Pb(1) and four equivalent Pb(3) atoms to form SPb6 octahedra that share corners with two equivalent Se(2)Pb6 octahedra, corners with four equivalent S(1)Pb6 octahedra, edges with four equivalent S(1)Pb6 octahedra, and edges with eight equivalent Se(1)Pb6 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_Pb4Se3S
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.333
_cell_length_b   4.333
_cell_length_c   12.286
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   230.704
_cell_formula_units_Z   1
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
  Pb  Pb0  1  0.000  0.000  0.255  1.0
  Pb  Pb1  1  0.500  0.500  0.000  1.0
  Pb  Pb2  1  0.000  0.000  0.745  1.0
  Pb  Pb3  1  0.500  0.500  0.500  1.0
  Se  Se4  1  0.500  0.500  0.251  1.0
  Se  Se5  1  0.000  0.000  0.000  1.0
  Se  Se6  1  0.500  0.500  0.749  1.0
  S  S7  1  0.000  0.000  0.500  1.0
[/CIF]
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The crystal structure described by Pb4Se3S is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Se(2), four equivalent Se(1), and one S(1) atom to form PbSe5S octahedra that share corners with six equivalent Pb(1)Se5S octahedra, edges with four equivalent Pb(3)Se2S4 octahedra, edges with four equivalent Pb(1)Se5S octahedra, and edges with four equivalent Pb(2)Se6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Pb site, Pb(2) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form PbSe6 octahedra that share corners with two equivalent Pb(3)Se2S4 octahedra, corners with four equivalent Pb(2)Se6 octahedra, edges with four equivalent Pb(2)Se6 octahedra, and edges with eight equivalent Pb(1)Se5S octahedra. The corner-sharing octahedra are not tilted. In the third Pb site, Pb(3) is bonded to two equivalent Se(1) and four equivalent S(1) atoms to form PbSe2S4 octahedra that share corners with two equivalent Pb(2)Se6 octahedra, corners with four equivalent Pb(3)Se2S4 octahedra, edges with four equivalent Pb(3)Se2S4 octahedra, and edges with eight equivalent Pb(1)Se5S octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to one Pb(2), one Pb(3), and four equivalent Pb(1) atoms to form SePb6 octahedra that share corners with six equivalent Se(1)Pb6 octahedra, edges with four equivalent Se(1)Pb6 octahedra, edges with four equivalent Se(2)Pb6 octahedra, and edges with four equivalent S(1)Pb6 octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the second Se site, Se(2) is bonded to two equivalent Pb(1) and four equivalent Pb(2) atoms to form SePb6 octahedra that share corners with two equivalent S(1)Pb6 octahedra, corners with four equivalent Se(2)Pb6 octahedra, edges with four equivalent Se(2)Pb6 octahedra, and edges with eight equivalent Se(1)Pb6 octahedra. The corner-sharing octahedra are not tilted. S(1) is bonded to two equivalent Pb(1) and four equivalent Pb(3) atoms to form SPb6 octahedra that share corners with two equivalent Se(2)Pb6 octahedra, corners with four equivalent S(1)Pb6 octahedra, edges with four equivalent S(1)Pb6 octahedra, and edges with eight equivalent Se(1)Pb6 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_Pb4Se3S
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.333
_cell_length_b   4.333
_cell_length_c   12.286
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   230.704
_cell_formula_units_Z   1
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
  Pb  Pb0  1  0.000  0.000  0.255  1.0
  Pb  Pb1  1  0.500  0.500  0.000  1.0
  Pb  Pb2  1  0.000  0.000  0.745  1.0
  Pb  Pb3  1  0.500  0.500  0.500  1.0
  Se  Se4  1  0.500  0.500  0.251  1.0
  Se  Se5  1  0.000  0.000  0.000  1.0
  Se  Se6  1  0.500  0.500  0.749  1.0
  S  S7  1  0.000  0.000  0.500  1.0
[/CIF]
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