data_[Cu6Ni3Se3]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Cu  1.9000  1.3500  0.8200
  Ni  1.9100  1.3500  0.7400
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [R3m]
_cell_length_a [2.8979]
_cell_length_b [2.8979]
_cell_length_c [23.1149]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [160]
_chemical_formula_structural [Cu2NiSe]
_chemical_formula_sum '[Cu6 Ni3 Se3]'
_cell_volume [168.1093]
_cell_formula_units_Z [3]
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  3  0.0000  0.0000  0.0044  1
  Cu  Cu1  3  0.0000  0.0000  0.7529  1
  Ni  Ni2  3  0.0000  0.0000  0.5016  1
  Se  Se3  3  0.0000  0.0000  0.2411  1
]