data_[Na2Er2P2O2]
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
  P  2.1900  1.0000  0.5500
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pmc2_1]
_cell_length_a [3.5595]
_cell_length_b [7.8713]
_cell_length_c [5.8700]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [26]
_chemical_formula_structural [NaErPO]
_chemical_formula_sum '[Na2 Er2 P2 O2]'
_cell_volume [164.4678]
_cell_formula_units_Z [2]
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  2  0.5000  0.4255  0.0362  1
  Er  Er1  2  0.0000  0.1785  0.4184  1
  P  P2  2  0.0000  0.1674  0.9063  1
  O  O3  2  0.5000  0.3170  0.3931  1
]