data_[Mg6Al18Ag18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Mg  1.3100  1.5000  0.8600
  Al  1.6100  1.2500  0.6750
  Ag  1.9300  1.6000  1.0867
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [7.7215]
_cell_length_b [7.7215]
_cell_length_c [15.9069]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Mg(AlAg)3]
_chemical_formula_sum '[Mg6 Al18 Ag18]'
_cell_volume [821.3350]
_cell_formula_units_Z [6]
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
[
  Mg  Mg0  6  0.0000  0.0000  0.3305  1.0
  Al  Al1  18  0.0006  0.6694  0.4540  1.0
  Ag  Ag2  18  0.0018  0.3137  0.0509  1.0
]