data_[Fe4Se8]
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
]
_symmetry_space_group_name_H-M [P-1]
_cell_length_a [6.4863]
_cell_length_b [6.4924]
_cell_length_c [6.9821]
_cell_angle_alpha [104.6454]
_cell_angle_beta [94.6041]
_cell_angle_gamma [117.0401]
_symmetry_Int_Tables_number [2]
_chemical_formula_structural [FeSe2]
_chemical_formula_sum '[Fe4 Se8]'
_cell_volume [246.7910]
_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  2  0.2810  0.7809  0.5005  1.0
  Fe  Fe1  2  0.2811  0.2088  0.4843  1.0
  Se  Se2  2  0.1241  0.9966  0.7100  1.0
  Se  Se3  2  0.1379  0.4756  0.6731  1.0
  Se  Se4  2  0.3581  0.4858  0.2902  1.0
  Se  Se5  2  0.3633  0.9680  0.2460  1.0
]