data_[Na8Er4O12]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Er  1.2400  1.7500  1.0300
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [5.9226]
_cell_length_b [10.2145]
_cell_length_c [5.9065]
_cell_angle_alpha [90.0000]
_cell_angle_beta [110.0421]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Na2ErO3]
_chemical_formula_sum '[Na8 Er4 O12]'
_cell_volume [335.6848]
_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
[
  Na  Na0  4  0.0000  0.3411  0.5000  1.0
  Na  Na1  2  0.0000  0.0000  0.5000  1.0
  Na  Na2  2  0.0000  0.5000  0.0000  1.0
  Er  Er3  4  0.0000  0.1659  0.0000  1.0
  O  O4  8  0.2426  0.1823  0.7812  1.0
  O  O5  4  0.2120  0.0000  0.2251  1.0
]