data_[Sn2Pb6Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Sn  1.9600  1.4500  0.8300
  Pb  2.3300  1.8000  1.1225
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Imm2]
_cell_length_a [6.1923]
_cell_length_b [12.3155]
_cell_length_c [6.2126]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [44]
_chemical_formula_structural [SnPb3Se4]
_chemical_formula_sum '[Sn2 Pb6 Se8]'
_cell_volume [473.7789]
_cell_formula_units_Z [2]
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
[
  Sn  Sn0  2  0.0000  0.5000  0.7989  1.0
  Pb  Pb1  4  0.0000  0.2496  0.3107  1.0
  Pb  Pb2  2  0.0000  0.0000  0.8081  1.0
  Se  Se3  4  0.0000  0.2534  0.8173  1.0
  Se  Se4  2  0.0000  0.0000  0.3178  1.0
  Se  Se5  2  0.0000  0.5000  0.3346  1.0
]