data_[Ca2Nb2Tl2O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  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 [P2_1/m]
_cell_length_a [6.3132]
_cell_length_b [6.2924]
_cell_length_c [7.5137]
_cell_angle_alpha [90.0000]
_cell_angle_beta [103.1497]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [CaNbTlO4]
_chemical_formula_sum '[Ca2 Nb2 Tl2 O8]'
_cell_volume [290.6546]
_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
[
  Ca  Ca0  2  0.1798  0.2500  0.5576  1
  Nb  Nb1  2  0.2974  0.7500  0.3574  1
  Tl  Tl2  2  0.2869  0.2500  0.0903  1
  O  O3  4  0.0984  0.5219  0.3422  1
  O  O4  2  0.4882  0.7500  0.1987  1
  O  O5  2  0.4926  0.7500  0.5833  1
]