data_[K4Nb6O16]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  K  0.8200  2.2000  1.5200
  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 [13.1984]
_cell_length_b [6.3706]
_cell_length_c [5.3155]
_cell_angle_alpha [90.0000]
_cell_angle_beta [109.4168]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [K2Nb3O8]
_chemical_formula_sum '[K4 Nb6 O16]'
_cell_volume [421.5189]
_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  4  0.2291  0.5000  0.6728  1.0
  Nb  Nb1  4  0.0000  0.2739  0.0000  1.0
  Nb  Nb2  2  0.0000  0.0000  0.5000  1.0
  O  O3  8  0.0849  0.2203  0.3816  1.0
  O  O4  4  0.0858  0.0000  0.8949  1.0
  O  O5  4  0.0993  0.5000  0.9607  1.0
]