The compound described by Pb4SeBr6 crystallizes in the orthorhombic Imm2 space group. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Se(1) and four equivalent Br(1) atoms to form edge-sharing PbSeBr4 square pyramids. In the second Pb site, Pb(2) is bonded in a 7-coordinate geometry to two equivalent Br(1), two equivalent Br(2), and three equivalent Br(3) atoms. In the third Pb site, Pb(3) is bonded in a see-saw-like geometry to two equivalent Se(1) and two equivalent Br(3) atoms. Se(1) is bonded in a trigonal planar geometry to one Pb(1) and two equivalent Pb(3) atoms. There are three 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(2) atoms. In the second Br site, Br(2) is bonded in an L-shaped geometry to two equivalent Pb(2) atoms. In the third Br site, Br(3) is bonded to one Pb(3) and three equivalent Pb(2) atoms to form corner-sharing BrPb4 tetrahedra. is represented by the CIF file [CIF]
data_Pb4SeBr6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.374
_cell_length_b   9.748
_cell_length_c   9.748
_cell_angle_alpha   62.901
_cell_angle_beta   77.034
_cell_angle_gamma   77.034
_symmetry_Int_Tables_number   1
_cell_volume   357.011
_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  0.500  0.492  0.508  1.0
  Pb  Pb1  1  0.259  0.515  0.966  1.0
  Pb  Pb2  1  0.000  0.036  0.964  1.0
  Pb  Pb3  1  0.741  0.034  0.485  1.0
  Se  Se4  1  0.500  0.213  0.787  1.0
  Br  Br5  1  0.136  0.328  0.400  1.0
  Br  Br6  1  0.864  0.600  0.672  1.0
  Br  Br7  1  0.378  0.912  0.333  1.0
  Br  Br8  1  0.622  0.667  0.088  1.0
  Br  Br9  1  0.192  0.883  0.734  1.0
  Br  Br10  1  0.808  0.266  0.117  1.0
[/CIF]
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The compound described by Pb4SeBr6 crystallizes in the orthorhombic Imm2 space group. There are three inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to one Se(1) and four equivalent Br(1) atoms to form edge-sharing PbSeBr4 square pyramids. In the second Pb site, Pb(2) is bonded in a 7-coordinate geometry to two equivalent Br(1), two equivalent Br(2), and three equivalent Br(3) atoms. In the third Pb site, Pb(3) is bonded in a see-saw-like geometry to two equivalent Se(1) and two equivalent Br(3) atoms. Se(1) is bonded in a trigonal planar geometry to one Pb(1) and two equivalent Pb(3) atoms. There are three 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(2) atoms. In the second Br site, Br(2) is bonded in an L-shaped geometry to two equivalent Pb(2) atoms. In the third Br site, Br(3) is bonded to one Pb(3) and three equivalent Pb(2) atoms to form corner-sharing BrPb4 tetrahedra. is represented by the CIF file [CIF]
data_Pb4SeBr6
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.374
_cell_length_b   9.748
_cell_length_c   9.748
_cell_angle_alpha   62.901
_cell_angle_beta   77.034
_cell_angle_gamma   77.034
_symmetry_Int_Tables_number   1
_cell_volume   357.011
_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  0.500  0.492  0.508  1.0
  Pb  Pb1  1  0.259  0.515  0.966  1.0
  Pb  Pb2  1  0.000  0.036  0.964  1.0
  Pb  Pb3  1  0.741  0.034  0.485  1.0
  Se  Se4  1  0.500  0.213  0.787  1.0
  Br  Br5  1  0.136  0.328  0.400  1.0
  Br  Br6  1  0.864  0.600  0.672  1.0
  Br  Br7  1  0.378  0.912  0.333  1.0
  Br  Br8  1  0.622  0.667  0.088  1.0
  Br  Br9  1  0.192  0.883  0.734  1.0
  Br  Br10  1  0.808  0.266  0.117  1.0
[/CIF]
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