data_[Fe2Ag4Se4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Fe  1.8300  1.4000  0.8525
  Ag  1.9300  1.6000  1.0867
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Pmma]
_cell_length_a [6.2213]
_cell_length_b [18.5372]
_cell_length_c [5.1627]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [51]
_chemical_formula_structural [Fe(AgSe)2]
_chemical_formula_sum '[Fe2 Ag4 Se4]'
_cell_volume [595.3842]
_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
[
  Fe  Fe0  2  0.0000  0.5000  0.0000  1
  Ag  Ag1  4  0.0000  0.4243  0.5000  1
  Se  Se2  4  0.2500  0.4046  0.8990  1
]