data_[Ca4Er8Se16]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Er  1.2400  1.7500  1.0300
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Cmcm]
_cell_length_a [4.0348]
_cell_length_b [13.3118]
_cell_length_c [13.9470]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [63]
_chemical_formula_structural [Ca(ErSe2)2]
_chemical_formula_sum '[Ca4 Er8 Se16]'
_cell_volume [749.0880]
_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
[
  Ca  Ca0  4  0.0000  0.3870  0.2500  1.0
  Er  Er1  8  0.0000  0.1344  0.0706  1.0
  Se  Se2  8  0.0000  0.2266  0.6175  1.0
  Se  Se3  4  0.0000  0.0428  0.2500  1.0
  Se  Se4  4  0.0000  0.5000  0.0000  1.0
]