data_[Na4Ni4O8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Ni  1.9100  1.3500  0.7400
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [C2/c]
_cell_length_a [3.0405]
_cell_length_b [5.0718]
_cell_length_c [10.6920]
_cell_angle_alpha [90.0000]
_cell_angle_beta [92.2097]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [15]
_chemical_formula_structural [NaNiO2]
_chemical_formula_sum '[Na4 Ni4 O8]'
_cell_volume [164.7545]
_cell_formula_units_Z [4]
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  4  0.0000  0.3419  0.2500  1.0
  Ni  Ni1  4  0.0000  0.0000  0.0000  1.0
  O  O2  8  0.0227  0.3203  0.9021  1.0
]