data_[Sr4Si2Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Sr  0.9500  2.0000  1.3200
  Si  1.9000  1.1000  0.5400
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [6.9727]
_cell_length_b [7.0019]
_cell_length_c [8.5708]
_cell_angle_alpha [90.0000]
_cell_angle_beta [107.9119]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [Sr2SiSe4]
_chemical_formula_sum '[Sr4 Si2 Se8]'
_cell_volume [398.1634]
_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
[
  Sr  Sr0  2  0.2396  0.2500  0.4342  1
  Sr  Sr1  2  0.2734  0.2500  0.9462  1
  Si  Si2  2  0.2761  0.7500  0.1991  1
  Se  Se3  4  0.4945  0.0030  0.2591  1
  Se  Se4  2  0.0864  0.7500  0.3754  1
  Se  Se5  2  0.1052  0.7500  0.9254  1
]