data_[Cu4Ag4Sn8Se16]
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
  Sn  1.9600  1.4500  0.8300
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Fmm2]
_cell_length_a [8.4598]
_cell_length_b [9.8005]
_cell_length_c [10.7714]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [42]
_chemical_formula_structural [CuAg(SnSe2)2]
_chemical_formula_sum '[Cu4 Ag4 Sn8 Se16]'
_cell_volume [893.0627]
_cell_formula_units_Z [4]
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  0.0000  0.0000  0.5078  1.0
  Ag  Ag1  4  0.0000  0.0000  0.0011  1.0
  Sn  Sn2  8  0.2500  0.2500  0.2661  1.0
  Se  Se3  8  0.0000  0.2318  0.6058  1.0
  Se  Se4  8  0.2318  0.0000  0.3737  1.0
]