data_[Na2Ti2Nb4O16]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Ti  1.5400  1.4000  0.8517
  Nb  1.6000  1.4500  0.8200
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [6.9762]
_cell_length_b [6.6219]
_cell_length_c [6.4160]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.7406]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [NaTiNb2O8]
_chemical_formula_sum '[Na2 Ti2 Nb4 O16]'
_cell_volume [296.3666]
_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  0.0000  0.5000  1
  Ti  Ti1  2  0.0000  0.0000  0.0000  1
  Nb  Nb2  4  0.0213  0.5000  0.7402  1
  O  O3  8  0.0019  0.2100  0.2109  1
  O  O4  4  0.1798  0.5000  0.4997  1
  O  O5  4  0.2029  0.5000  0.9962  1
]