data_[Rb4Fe4O8]
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
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pna2_1]
_cell_length_a [5.9619]
_cell_length_b [8.1205]
_cell_length_c [5.9320]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [33]
_chemical_formula_structural [RbFeO2]
_chemical_formula_sum '[Rb4 Fe4 O8]'
_cell_volume [287.1882]
_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
[
  Rb  Rb0  4  0.0635  0.3777  0.4858  1.0
  Fe  Fe1  4  0.0469  0.8737  0.4992  1.0
  O  O2  4  0.0071  0.9512  0.7971  1.0
  O  O3  4  0.1516  0.3057  0.9578  1.0
]