data_[Cu2Se1]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Cu  1.9000  1.3500  0.8200
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Pm]
_cell_length_a [16.2079]
_cell_length_b [4.2844]
_cell_length_c [16.2079]
_cell_angle_alpha [90.0000]
_cell_angle_beta [120.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [6]
_chemical_formula_structural [Cu2Se]
_chemical_formula_sum '[Cu2 Se1]'
_cell_volume [974.7067]
_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  0.0078  0.0000  0.4923  1
  Cu  Cu1  1  0.9322  0.5000  0.5120  1
  Se  Se2  1  0.0600  0.5000  0.4957  1
]