data_[Na4Mg12Tl8]
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
  Tl  1.6200  1.9000  1.3325
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [16.8420]
_cell_length_b [4.4904]
_cell_length_c [9.6824]
_cell_angle_alpha [90.0000]
_cell_angle_beta [123.5647]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [NaMg3Tl2]
_chemical_formula_sum '[Na4 Mg12 Tl8]'
_cell_volume [610.1617]
_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  0.0843  0.0000  0.9641  1.0
  Mg  Mg1  4  0.0820  0.0000  0.4645  1.0
  Mg  Mg2  4  0.0867  0.5000  0.6996  1.0
  Mg  Mg3  4  0.2450  0.0000  0.3773  1.0
  Tl  Tl4  4  0.0845  0.5000  0.2395  1.0
  Tl  Tl5  4  0.2474  0.0000  0.8578  1.0
]