data_[Er8Se12]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Er  1.2400  1.7500  1.0300
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [7.0439]
_cell_length_b [12.1871]
_cell_length_c [7.0058]
_cell_angle_alpha [90.0000]
_cell_angle_beta [109.5130]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Er2Se3]
_chemical_formula_sum '[Er8 Se12]'
_cell_volume [566.8698]
_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
[
  Er  Er0  4  0.0000  0.3324  0.5000  1.0
  Er  Er1  2  0.0000  0.0000  0.5000  1.0
  Er  Er2  2  0.0000  0.5000  0.0000  1.0
  Se  Se3  8  0.2489  0.3367  0.2558  1.0
  Se  Se4  4  0.2414  0.5000  0.7465  1.0
]