data_[K2Ba2Nb2O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  K  0.8200  2.2000  1.5200
  Ba  0.8900  2.1500  1.4900
  Nb  1.6000  1.4500  0.8200
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [I4mm]
_cell_length_a [4.0911]
_cell_length_b [4.0911]
_cell_length_c [13.6166]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [107]
_chemical_formula_structural [KBaNbO4]
_chemical_formula_sum '[K2 Ba2 Nb2 O8]'
_cell_volume [227.8996]
_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
[
  K  K0  2  0.0000  0.0000  0.3496  1.0
  Ba  Ba1  2  0.0000  0.0000  0.6515  1.0
  Nb  Nb2  2  0.0000  0.0000  0.9944  1.0
  O  O3  4  0.0000  0.5000  0.0025  1.0
  O  O4  2  0.0000  0.0000  0.1467  1.0
  O  O5  2  0.0000  0.0000  0.8529  1.0
]