data_[Pb8Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Pb  2.3300  1.8000  1.1225
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Cccm]
_cell_length_a [20.3980]
_cell_length_b [35.3303]
_cell_length_c [3.2579]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [66]
_chemical_formula_structural [PbSe]
_chemical_formula_sum '[Pb8 Se8]'
_cell_volume [2347.8743]
_cell_formula_units_Z [8]
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  8  0.0732  0.1468  0.0000  1
  Se  Se1  8  0.0502  0.0681  0.0000  1
]