data_[Rb2Fe2Si2O8]
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
  Si  1.9000  1.1000  0.5400
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [5.1488]
_cell_length_b [5.5439]
_cell_length_c [7.3185]
_cell_angle_alpha [90.0000]
_cell_angle_beta [96.5765]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [RbFeSiO4]
_chemical_formula_sum '[Rb2 Fe2 Si2 O8]'
_cell_volume [207.5270]
_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  0.2878  0.2500  0.9055  1
  Fe  Fe1  2  0.3218  0.7500  0.5284  1
  Si  Si2  2  0.1508  0.2500  0.3553  1
  O  O3  4  0.3639  0.0248  0.3399  1
  O  O4  2  0.0531  0.2500  0.5608  1
  O  O5  2  0.1264  0.7500  0.7775  1
]