data_[Cu6Ag2Se6]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Cu  1.9000  1.3500  0.8200
  Ag  1.9300  1.6000  1.0867
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Cm]
_cell_length_a [9.5555]
_cell_length_b [5.5771]
_cell_length_c [18.6500]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [8]
_chemical_formula_structural [Cu3AgSe3]
_chemical_formula_sum '[Cu6 Ag2 Se6]'
_cell_volume [993.8976]
_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
[
  Cu  Cu0  4  0.2143  0.2291  0.4793  1
  Cu  Cu1  2  0.4575  0.5000  0.4931  1
  Ag  Ag2  2  0.4795  0.0000  0.4822  1
  Se  Se3  4  0.3307  0.2778  0.5873  1
  Se  Se4  2  0.1040  0.0000  0.3916  1
]