data_[Pm8Si4O16]
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
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pnma]
_cell_length_a [6.7486]
_cell_length_b [5.4712]
_cell_length_c [10.2245]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [62]
_chemical_formula_structural [Pm2SiO4]
_chemical_formula_sum '[Pm8 Si4 O16]'
_cell_volume [377.5201]
_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
[
  Pm  Pm0  4  0.0300  0.2500  0.8123  1
  Pm  Pm1  4  0.1135  0.2500  0.4498  1
  Si  Si2  4  0.1602  0.2500  0.1614  1
  O  O3  8  0.1962  0.5043  0.6303  1
  O  O4  4  0.0330  0.7500  0.9432  1
  O  O5  4  0.1522  0.7500  0.3834  1
]