data_[Fe8Se8O28]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Fe  1.8300  1.4000  0.8525
  Se  2.5500  1.1500  1.0133
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [C2/c]
_cell_length_a [8.4325]
_cell_length_b [8.3176]
_cell_length_c [9.9481]
_cell_angle_alpha [90.0000]
_cell_angle_beta [112.4592]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [15]
_chemical_formula_structural [Fe2Se2O7]
_chemical_formula_sum '[Fe8 Se8 O28]'
_cell_volume [644.8218]
_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
[
  Fe  Fe0  8  0.1700  0.0682  0.9742  1
  Se  Se1  8  0.2455  0.2542  0.2998  1
  O  O2  8  0.0957  0.1096  0.5941  1
  O  O3  8  0.1982  0.4237  0.6107  1
  O  O4  8  0.2082  0.2732  0.8548  1
  O  O5  4  0.0000  0.2867  0.2500  1
]