data_[K4Cu4As2Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  K  0.8200  2.2000  1.5200
  Cu  1.9000  1.3500  0.8200
  As  2.1800  1.1500  0.6600
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [14.9659]
_cell_length_b [3.9310]
_cell_length_c [7.7868]
_cell_angle_alpha [90.0000]
_cell_angle_beta [110.5358]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [K2Cu2AsSe4]
_chemical_formula_sum '[K4 Cu4 As2 Se8]'
_cell_volume [428.9967]
_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
[
  K  K0  4  0.1324  0.0000  0.5559  1.0
  Cu  Cu1  4  0.1919  0.5000  0.9864  1.0
  As  As2  2  0.0000  0.0000  0.0000  1.0
  Se  Se3  4  0.0223  0.5000  0.7774  1.0
  Se  Se4  4  0.1936  0.0000  0.1770  1.0
]