data_[Cu1Ag1Se2]
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 [Pmm2]
_cell_length_a [2.9903]
_cell_length_b [4.0977]
_cell_length_c [6.6406]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [25]
_chemical_formula_structural [CuAgSe2]
_chemical_formula_sum '[Cu1 Ag1 Se2]'
_cell_volume [81.3683]
_cell_formula_units_Z [1]
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  1  0.5000  0.5000  0.2829  1
  Ag  Ag1  1  0.0000  0.0000  0.4717  1
  Se  Se2  1  0.5000  0.0000  0.0818  1
  Se  Se3  1  0.5000  0.5000  0.6637  1
]