data_[Na8Cu4Sn8]
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
  Sn  1.9600  1.4500  0.8300
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [10.9354]
_cell_length_b [4.5760]
_cell_length_c [11.3812]
_cell_angle_alpha [90.0000]
_cell_angle_beta [118.3174]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [Na2CuSn2]
_chemical_formula_sum '[Na8 Cu4 Sn8]'
_cell_volume [501.3672]
_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  0.0806  0.0000  0.8875  1.0
  Na  Na1  4  0.1637  0.5000  0.6800  1.0
  Cu  Cu2  4  0.1341  0.5000  0.3466  1.0
  Sn  Sn3  4  0.1034  0.0000  0.4394  1.0
  Sn  Sn4  4  0.1361  0.5000  0.1185  1.0
]