data_[Er4Ag2Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Er  1.2400  1.7500  1.0300
  Ag  1.9300  1.6000  1.0867
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [6.9066]
_cell_length_b [5.6270]
_cell_length_c [8.7652]
_cell_angle_alpha [90.0000]
_cell_angle_beta [98.9629]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [Er2AgSe4]
_chemical_formula_sum '[Er4 Ag2 Se8]'
_cell_volume [336.4853]
_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
[
  Er  Er0  2  0.1526  0.2500  0.8530  1
  Er  Er1  2  0.2372  0.2500  0.4336  1
  Ag  Ag2  2  0.3783  0.7500  0.0353  1
  Se  Se3  4  0.4514  0.5052  0.7118  1
  Se  Se4  2  0.0205  0.7500  0.8737  1
  Se  Se5  2  0.0976  0.7500  0.4140  1
]