data_[Na4Cu8O8]
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
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Pnma]
_cell_length_a [6.1008]
_cell_length_b [2.9528]
_cell_length_c [13.1611]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [62]
_chemical_formula_structural [Na(CuO)2]
_chemical_formula_sum '[Na4 Cu8 O8]'
_cell_volume [237.0914]
_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  0.1515  0.2500  0.4238  1
  Cu  Cu1  4  0.1104  0.2500  0.7411  1
  Cu  Cu2  4  0.1361  0.2500  0.1118  1
  O  O3  4  0.0759  0.2500  0.8791  1
  O  O4  4  0.1460  0.2500  0.6017  1
]