data_[Fe12Se16]
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 [Aem2]
_cell_length_a [19.6582]
_cell_length_b [9.4898]
_cell_length_c [13.0947]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [39]
_chemical_formula_structural [Fe3Se4]
_chemical_formula_sum '[Fe12 Se16]'
_cell_volume [2442.8445]
_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  0.0280  0.1145  0.7440  1
  Fe  Fe1  4  0.0000  0.0000  0.0721  1
  Se  Se2  8  0.0849  0.0857  0.1731  1
  Se  Se3  4  0.0000  0.0000  0.3986  1
  Se  Se4  4  0.1185  0.2500  0.7877  1
]