data_[Pm9Si6Ni21]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Pm  1.1300  1.8500  1.1100
  Si  1.9000  1.1000  0.5400
  Ni  1.9100  1.3500  0.7400
]
_symmetry_space_group_name_H-M [R-3m]
_cell_length_a [5.2190]
_cell_length_b [5.2190]
_cell_length_c [23.4478]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [166]
_chemical_formula_structural [Pm3Si2Ni7]
_chemical_formula_sum '[Pm9 Si6 Ni21]'
_cell_volume [553.1090]
_cell_formula_units_Z [3]
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
[
  Pm  Pm0  6  0.0000  0.0000  0.1424  1
  Pm  Pm1  3  0.0000  0.0000  0.0000  1
  Si  Si2  6  0.0000  0.0000  0.3312  1
  Ni  Ni3  18  0.0061  0.5030  0.0767  1
  Ni  Ni4  3  -0.0000  -0.0000  0.5000  1
]