data_[Rb2Nb2Tl4O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  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 [Pmn2_1]
_cell_length_a [8.3330]
_cell_length_b [8.1660]
_cell_length_c [6.0447]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [31]
_chemical_formula_structural [RbNbTl2O4]
_chemical_formula_sum '[Rb2 Nb2 Tl4 O8]'
_cell_volume [411.3242]
_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
[
  Rb  Rb0  2  0.0000  0.1434  0.5062  1.0
  Nb  Nb1  2  0.0000  0.8742  0.9976  1.0
  Tl  Tl2  4  0.2475  0.6839  0.5044  1.0
  O  O3  4  0.1834  0.7928  0.1379  1.0
  O  O4  2  0.0000  0.1057  0.0204  1.0
  O  O5  2  0.0000  0.8190  0.6913  1.0
]