data_[Mg4Sn4Pb8Se20]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  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 [Cmc2_1]
_cell_length_a [4.0789]
_cell_length_b [19.2457]
_cell_length_c [13.1229]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [36]
_chemical_formula_structural [MgSnPb2Se5]
_chemical_formula_sum '[Mg4 Sn4 Pb8 Se20]'
_cell_volume [1030.1698]
_cell_formula_units_Z [4]
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
[
  Mg  Mg0  4  0.0000  0.1999  0.0269  1.0
  Sn  Sn1  4  0.0000  0.4491  0.4252  1.0
  Pb  Pb2  4  0.0000  0.1381  0.3249  1.0
  Pb  Pb3  4  0.0000  0.1506  0.6680  1.0
  Se  Se4  4  0.0000  0.0373  0.0502  1.0
  Se  Se5  4  0.0000  0.2998  0.6695  1.0
  Se  Se6  4  0.0000  0.3196  0.3805  1.0
  Se  Se7  4  0.0000  0.3379  0.0102  1.0
  Se  Se8  4  0.0000  0.4749  0.7685  1.0
]