The material described by Pb4SeBr6 crystallizes in the monoclinic Cm space group. There are four inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Se(1), two equivalent Br(1), and two equivalent Br(2) atoms to form edge-sharing PbSeBr4 square pyramids. In the second Pb site, Pb(2) is bonded in a 7-coordinate geometry to one Br(5), two equivalent Br(2), two equivalent Br(4), and two equivalent Br(6) atoms. In the third Pb site, Pb(3) is bonded in a rectangular see-saw-like geometry to two equivalent Se(1), one Br(5), and one Br(6) atom. In the fourth Pb site, Pb(4) is bonded in a 7-coordinate geometry to one Br(6), two equivalent Br(1), two equivalent Br(3), and two equivalent Br(5) atoms. Se(1) is bonded in a trigonal planar geometry to one Pb(1) and two equivalent Pb(3) atoms. There are six inequivalent Br sites. In the first Br site, Br(1) is bonded in a distorted L-shaped geometry to two equivalent Pb(1) and two equivalent Pb(4) atoms. In the second Br site, Br(2) is bonded in a distorted L-shaped geometry to two equivalent Pb(1) and two equivalent Pb(2) atoms. In the third Br site, Br(3) is bonded in an L-shaped geometry to two equivalent Pb(4) atoms. In the fourth Br site, Br(4) is bonded in an L-shaped geometry to two equivalent Pb(2) atoms. In the fifth Br site, Br(5) is bonded to one Pb(2), one Pb(3), and two equivalent Pb(4) atoms to form corner-sharing BrPb4 tetrahedra. In the sixth Br site, Br(6) is bonded to one Pb(3), one Pb(4), and two equivalent Pb(2) atoms to form corner-sharing BrPb4 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Pb4SeBr6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.654
_cell_length_b   9.654
_cell_length_c   10.171
_cell_angle_alpha   59.330
_cell_angle_beta   59.330
_cell_angle_gamma   26.430
_symmetry_Int_Tables_number   1
_cell_volume   359.346
_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  0.996  0.996  0.998  1.0
  Pb  Pb1  1  0.753  0.753  0.019  1.0
  Pb  Pb2  1  0.496  0.496  0.536  1.0
  Pb  Pb3  1  0.233  0.233  0.541  1.0
  Se  Se4  1  0.004  0.004  0.707  1.0
  Br  Br5  1  0.632  0.632  0.836  1.0
  Br  Br6  1  0.362  0.362  0.100  1.0
  Br  Br7  1  0.871  0.871  0.419  1.0
  Br  Br8  1  0.119  0.119  0.169  1.0
  Br  Br9  1  0.687  0.687  0.383  1.0
  Br  Br10  1  0.307  0.307  0.768  1.0
[/CIF]
.
The material described by Pb4SeBr6 crystallizes in the monoclinic Cm space group. There are four inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Se(1), two equivalent Br(1), and two equivalent Br(2) atoms to form edge-sharing PbSeBr4 square pyramids. In the second Pb site, Pb(2) is bonded in a 7-coordinate geometry to one Br(5), two equivalent Br(2), two equivalent Br(4), and two equivalent Br(6) atoms. In the third Pb site, Pb(3) is bonded in a rectangular see-saw-like geometry to two equivalent Se(1), one Br(5), and one Br(6) atom. In the fourth Pb site, Pb(4) is bonded in a 7-coordinate geometry to one Br(6), two equivalent Br(1), two equivalent Br(3), and two equivalent Br(5) atoms. Se(1) is bonded in a trigonal planar geometry to one Pb(1) and two equivalent Pb(3) atoms. There are six inequivalent Br sites. In the first Br site, Br(1) is bonded in a distorted L-shaped geometry to two equivalent Pb(1) and two equivalent Pb(4) atoms. In the second Br site, Br(2) is bonded in a distorted L-shaped geometry to two equivalent Pb(1) and two equivalent Pb(2) atoms. In the third Br site, Br(3) is bonded in an L-shaped geometry to two equivalent Pb(4) atoms. In the fourth Br site, Br(4) is bonded in an L-shaped geometry to two equivalent Pb(2) atoms. In the fifth Br site, Br(5) is bonded to one Pb(2), one Pb(3), and two equivalent Pb(4) atoms to form corner-sharing BrPb4 tetrahedra. In the sixth Br site, Br(6) is bonded to one Pb(3), one Pb(4), and two equivalent Pb(2) atoms to form corner-sharing BrPb4 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Pb4SeBr6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.654
_cell_length_b   9.654
_cell_length_c   10.171
_cell_angle_alpha   59.330
_cell_angle_beta   59.330
_cell_angle_gamma   26.430
_symmetry_Int_Tables_number   1
_cell_volume   359.346
_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  0.996  0.996  0.998  1.0
  Pb  Pb1  1  0.753  0.753  0.019  1.0
  Pb  Pb2  1  0.496  0.496  0.536  1.0
  Pb  Pb3  1  0.233  0.233  0.541  1.0
  Se  Se4  1  0.004  0.004  0.707  1.0
  Br  Br5  1  0.632  0.632  0.836  1.0
  Br  Br6  1  0.362  0.362  0.100  1.0
  Br  Br7  1  0.871  0.871  0.419  1.0
  Br  Br8  1  0.119  0.119  0.169  1.0
  Br  Br9  1  0.687  0.687  0.383  1.0
  Br  Br10  1  0.307  0.307  0.768  1.0
[/CIF]
.