data_OsPbSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.22
_cell_length_b   7.22
_cell_length_c   7.22
_cell_angle_alpha   155.16
_cell_angle_beta   155.16
_cell_angle_gamma   35.42
_symmetry_Int_Tables_number   1
_chemical_formula_structural   OsPbSe
_chemical_formula_sum   'Os1 Pb1 Se1'
_cell_volume   66.34
_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
  Os  Os0  1  0.0  0.0  0.42  1.0
  Pb  Pb1  1  0.0  0.0  0.83  1.0
  Se  Se2  1  0.0  0.0  0.25  1.0

data_OsPbSe
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.39
_cell_length_b   4.39
_cell_length_c   7.22
_cell_angle_alpha   90.0
_cell_angle_beta   107.71
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   OsPbSe
_chemical_formula_sum   'Os2 Pb2 Se2'
_cell_volume   132.68
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Os  Os0  2  0.42  0.0  0.42  1.0
  Pb  Pb1  2  0.33  0.5  0.83  1.0
  Se  Se2  2  0.25  0.0  0.25  1.0

Os Pb Se
OsPbSe crystallizes in the monoclinic Cm space group. Os(1) is bonded in a single-bond geometry to one Pb(1) and one Se(1) atom. The Os(1)-Pb(1) bond length is 2.97 Å. The Os(1)-Se(1) bond length is 1.22 Å. Pb(1) is bonded to one Os(1), four equivalent Pb(1), and one Se(1) atom to form a mixture of distorted corner and edge-sharing PbOsPb4Se octahedra. The corner-sharing octahedra are not tilted. All Pb(1)-Pb(1) bond lengths are 3.11 Å. The Pb(1)-Se(1) bond length is 3.02 Å. Se(1) is bonded in a single-bond geometry to one Os(1) and one Pb(1) atom.