data_[Na1Cu1Ni1Se2]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  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 [P2/m]
_cell_length_a [3.5683]
_cell_length_b [3.9359]
_cell_length_c [6.7956]
_cell_angle_alpha [90.0000]
_cell_angle_beta [92.6120]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [10]
_chemical_formula_structural [NaCuNiSe2]
_chemical_formula_sum '[Na1 Cu1 Ni1 Se2]'
_cell_volume [95.3422]
_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
[
  Na  Na0  1  0.5000  0.0000  0.5000  1.0
  Cu  Cu1  1  0.0000  0.0000  0.0000  1.0
  Ni  Ni2  1  0.5000  0.5000  0.0000  1.0
  Se  Se3  2  0.0198  0.5000  0.2333  1.0
]