data_[Na4Cu2Cl8]
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
  Cl  3.1600  1.0000  0.7800
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [6.7879]
_cell_length_b [6.8658]
_cell_length_c [7.6670]
_cell_angle_alpha [90.0000]
_cell_angle_beta [106.6000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [Na2CuCl4]
_chemical_formula_sum '[Na4 Cu2 Cl8]'
_cell_volume [342.4246]
_cell_formula_units_Z [2]
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  2  0.2622  0.2500  0.4411  1.0
  Na  Na1  2  0.2863  0.2500  0.9473  1.0
  Cu  Cu2  2  0.2486  0.7500  0.1905  1.0
  Cl  Cl3  4  0.4848  0.5059  0.2501  1.0
  Cl  Cl4  2  0.0385  0.7500  0.3716  1.0
  Cl  Cl5  2  0.0453  0.7500  0.9002  1.0
]