data_[Ac4Pb20Se28]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ac  1.1000  1.9500  1.2600
  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 [4.3524]
_cell_length_b [14.4600]
_cell_length_c [25.2950]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [36]
_chemical_formula_structural [AcPb5Se7]
_chemical_formula_sum '[Ac4 Pb20 Se28]'
_cell_volume [1591.9483]
_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
[
  Ac  Ac0  4  0.0000  0.2975  0.2579  1
  Pb  Pb1  4  0.0000  0.0337  0.3515  1
  Pb  Pb2  4  0.0000  0.0521  0.1490  1
  Pb  Pb3  4  0.0000  0.2183  0.5758  1
  Pb  Pb4  4  0.0000  0.2330  0.9251  1
  Pb  Pb5  4  0.0000  0.4945  0.5019  1
  Se  Se6  4  0.0000  0.0529  0.7483  1
  Se  Se7  4  0.0000  0.1309  0.4627  1
  Se  Se8  4  0.0000  0.1422  0.0369  1
  Se  Se9  4  0.0000  0.3028  0.6825  1
  Se  Se10  4  0.0000  0.3216  0.8209  1
  Se  Se11  4  0.0000  0.3919  0.3795  1
  Se  Se12  4  0.0000  0.4182  0.1082  1
]