data_[Er4Se8]
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 [P2_1/c]
_cell_length_a [8.2510]
_cell_length_b [4.0601]
_cell_length_c [8.2014]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.1179]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [14]
_chemical_formula_structural [ErSe2]
_chemical_formula_sum '[Er4 Se8]'
_cell_volume [274.7470]
_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  0.2731  0.7279  0.6260  1.0
  Se  Se1  4  0.0017  0.2007  0.6214  1.0
  Se  Se2  4  0.3707  0.2449  0.8748  1.0
]