data_[Na1Cu2Ag1Se2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  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 [P-3m1]
_cell_length_a [4.1052]
_cell_length_b [4.1052]
_cell_length_c [7.8262]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [164]
_chemical_formula_structural [NaCu2AgSe2]
_chemical_formula_sum '[Na1 Cu2 Ag1 Se2]'
_cell_volume [114.2199]
_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
[
  Na  Na0  1  0.0000  0.0000  0.0000  1.0
  Cu  Cu1  2  0.3333  0.6667  0.6937  1.0
  Ag  Ag2  1  0.0000  0.0000  0.5000  1.0
  Se  Se3  2  0.3333  0.6667  0.2501  1.0
]