data_[Ge4Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ge  2.0100  1.2500  0.7700
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Aem2]
_cell_length_a [16.6696]
_cell_length_b [10.1487]
_cell_length_c [6.8821]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [39]
_chemical_formula_structural [GeSe2]
_chemical_formula_sum '[Ge4 Se8]'
_cell_volume [1164.2830]
_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
[
  Ge  Ge0  4  0.4499  0.2500  0.0803  1
  Se  Se1  8  0.4517  0.0866  0.7382  1
]