data_[K8Nb4Tl4O16]
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
  Tl  1.6200  1.9000  1.3325
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Fmm2]
_cell_length_a [8.0505]
_cell_length_b [8.3070]
_cell_length_c [10.9319]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [42]
_chemical_formula_structural [K2NbTlO4]
_chemical_formula_sum '[K8 Nb4 Tl4 O16]'
_cell_volume [731.0793]
_cell_formula_units_Z [4]
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  8  0.2500  0.2500  0.2506  1.0
  Nb  Nb1  4  0.0000  0.0000  0.4988  1.0
  Tl  Tl2  4  0.0000  0.0000  0.0061  1.0
  O  O3  8  0.0000  0.1851  0.5984  1.0
  O  O4  8  0.1916  0.0000  0.3987  1.0
]