data_[Sm4Al4Pb8Se20]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Sm  1.1700  1.8500  1.2290
  Al  1.6100  1.2500  0.6750
  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 [4.1118]
_cell_length_b [18.7798]
_cell_length_c [13.3923]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [36]
_chemical_formula_structural [SmAlPb2Se5]
_chemical_formula_sum '[Sm4 Al4 Pb8 Se20]'
_cell_volume [1034.1411]
_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
[
  Sm  Sm0  4  0.0000  0.1947  0.0323  1.0
  Al  Al1  4  0.0000  0.4450  0.4182  1.0
  Pb  Pb2  4  0.0000  0.1121  0.3338  1.0
  Pb  Pb3  4  0.0000  0.1424  0.6741  1.0
  Se  Se4  4  0.0000  0.0320  0.0186  1.0
  Se  Se5  4  0.0000  0.3014  0.6858  1.0
  Se  Se6  4  0.0000  0.3194  0.3762  1.0
  Se  Se7  4  0.0000  0.3476  0.0189  1.0
  Se  Se8  4  0.0000  0.4906  0.7661  1.0
]