data_[Na2Er2P4O14]
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 [C2]
_cell_length_a [6.9719]
_cell_length_b [8.9469]
_cell_length_c [4.7521]
_cell_angle_alpha [90.0000]
_cell_angle_beta [101.5233]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [5]
_chemical_formula_structural [NaErP2O7]
_chemical_formula_sum '[Na2 Er2 P4 O14]'
_cell_volume [290.4440]
_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  0.0000  0.2497  0.0000  1.0
  Er  Er1  2  0.0000  0.6336  0.0000  1.0
  P  P2  4  0.2021  0.9625  0.4182  1.0
  O  O3  4  0.1491  0.4524  0.2984  1.0
  O  O4  4  0.1653  0.8117  0.2661  1.0
  O  O5  4  0.2490  0.5866  0.7796  1.0
  O  O6  2  0.0000  0.0234  0.5000  1.0
]