data_[Na6Mg8Sn8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Mg  1.3100  1.5000  0.8600
  Sn  1.9600  1.4500  0.8300
]
_symmetry_space_group_name_H-M [Immm]
_cell_length_a [4.6985]
_cell_length_b [8.0941]
_cell_length_c [15.7877]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [71]
_chemical_formula_structural [Na3(MgSn)4]
_chemical_formula_sum '[Na6 Mg8 Sn8]'
_cell_volume [600.4074]
_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  4  0.0000  0.0000  0.1211  1.0
  Na  Na1  2  0.0000  0.5000  0.0000  1.0
  Mg  Mg2  8  0.0000  0.2003  0.3260  1.0
  Sn  Sn3  4  0.0000  0.3189  0.5000  1.0
  Sn  Sn4  4  0.0000  0.5000  0.2168  1.0
]