data_[Pm21Nd36Mg3]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Pm  1.1300  1.8500  1.1100
  Nd  1.1400  1.8500  1.2765
  Mg  1.3100  1.5000  0.8600
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [12.3508]
_cell_length_b [12.3508]
_cell_length_c [15.9319]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Pm7Nd12Mg]
_chemical_formula_sum '[Pm21 Nd36 Mg3]'
_cell_volume [2104.6993]
_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  18  0.0556  0.8691  0.7966  1
  Pm  Pm1  3  -0.0000  0.0000  0.5000  1
  Nd  Nd2  18  0.0299  0.5791  0.7155  1
  Nd  Nd3  18  0.0556  0.4682  0.0834  1
  Mg  Mg4  3  0.0000  0.0000  0.0000  1
]