data_[Rb4Ca4Ta2O12]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  Ca  1.0000  1.8000  1.1400
  Ta  1.5000  1.4500  0.8200
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [5.9424]
_cell_length_b [10.1229]
_cell_length_c [6.8884]
_cell_angle_alpha [90.0000]
_cell_angle_beta [107.3875]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Rb2Ca2TaO6]
_chemical_formula_sum '[Rb4 Ca4 Ta2 O12]'
_cell_volume [395.4284]
_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  4  0.0000  0.1698  0.0000  1
  Ca  Ca1  4  0.0000  0.3376  0.5000  1
  Ta  Ta2  2  0.0000  0.0000  0.5000  1
  O  O3  8  0.1987  0.1469  0.6666  1
  O  O4  4  0.2275  0.0000  0.3331  1
]