data_[Rb4Fe2Sb2O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Rb  0.8200  2.3500  1.6600
  Fe  1.8300  1.4000  0.8525
  Sb  2.0500  1.4500  0.8300
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [C2]
_cell_length_a [8.3123]
_cell_length_b [7.6302]
_cell_length_c [5.9704]
_cell_angle_alpha [90.0000]
_cell_angle_beta [127.0440]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [5]
_chemical_formula_structural [Rb2FeSbO4]
_chemical_formula_sum '[Rb4 Fe2 Sb2 O8]'
_cell_volume [302.2454]
_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  0.0034  0.5000  1
  Rb  Rb1  2  0.0000  0.2637  0.0000  1
  Fe  Fe2  2  0.0000  0.4783  0.5000  1
  Sb  Sb3  2  0.0000  0.7775  0.0000  1
  O  O4  4  0.0966  0.6084  0.8459  1
  O  O5  4  0.2074  0.3236  0.5865  1
]