data_[Cu2As1Se4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  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 [P-42m]
_cell_length_a [5.6219]
_cell_length_b [5.6219]
_cell_length_c [5.1516]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [111]
_chemical_formula_structural [Cu2AsSe4]
_chemical_formula_sum '[Cu2 As1 Se4]'
_cell_volume [162.8243]
_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  2  0.0000  0.5000  0.5000  1.0
  As  As1  1  0.0000  0.0000  0.0000  1.0
  Se  Se2  4  0.2622  0.2622  0.7589  1.0
]