data_[K6Nb16O42]
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 [P6_3/mcm]
_cell_length_a [9.2185]
_cell_length_b [9.2185]
_cell_length_c [11.9854]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [193]
_chemical_formula_structural [K3Nb8O21]
_chemical_formula_sum '[K6 Nb16 O42]'
_cell_volume [882.0614]
_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  6  0.0000  0.4057  0.7500  1
  Nb  Nb1  12  0.0000  0.2493  0.0947  1
  Nb  Nb2  4  0.3333  0.6667  0.5000  1
  O  O3  24  0.1684  0.4827  0.0987  1
  O  O4  12  0.0000  0.2036  0.5737  1
  O  O5  6  0.0000  0.1960  0.2500  1
]