data_[Ca18Fe12Se36O108]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  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 [R-3c]
_cell_length_a [8.6458]
_cell_length_b [8.6458]
_cell_length_c [39.8285]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [167]
_chemical_formula_structural [Ca3Fe2(SeO3)6]
_chemical_formula_sum '[Ca18 Fe12 Se36 O108]'
_cell_volume [2578.3309]
_cell_formula_units_Z [6]
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
[
  Ca  Ca0  18  0.0000  0.5906  0.7500  1
  Fe  Fe1  6  0.0000  0.0000  0.2500  1
  Fe  Fe2  6  0.0000  0.0000  0.0000  1
  Se  Se3  36  0.0108  0.2966  0.8029  1
  O  O4  36  0.0599  0.2275  0.3913  1
  O  O5  36  0.0631  0.2101  0.0312  1
  O  O6  36  0.0958  0.8753  0.7195  1
]