data_[Er2Ag6Se6]
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 [Amm2]
_cell_length_a [19.4042]
_cell_length_b [4.7863]
_cell_length_c [14.0790]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [38]
_chemical_formula_structural [Er(AgSe)3]
_chemical_formula_sum '[Er2 Ag6 Se6]'
_cell_volume [1307.5912]
_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  0.0000  0.0000  0.6510  1
  Ag  Ag1  4  0.1043  0.0000  0.1980  1
  Ag  Ag2  2  0.0000  0.0000  0.8717  1
  Se  Se3  4  0.1135  0.0000  0.7681  1
  Se  Se4  2  0.0000  0.0000  0.0562  1
]