data_[Na3Ac36Si21]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Ac  1.1000  1.9500  1.2600
  Si  1.9000  1.1000  0.5400
]
_symmetry_space_group_name_H-M [R-3m]
_cell_length_a [16.2486]
_cell_length_b [16.2486]
_cell_length_c [9.1684]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [166]
_chemical_formula_structural [NaAc12Si7]
_chemical_formula_sum '[Na3 Ac36 Si21]'
_cell_volume [2096.2976]
_cell_formula_units_Z [3]
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  3  0.0000  0.0000  0.0000  1
  Ac  Ac1  18  0.0000  0.2605  0.0000  1
  Ac  Ac2  18  0.0979  0.9021  0.3635  1
  Si  Si3  18  0.0985  0.5493  0.4006  1
  Si  Si4  3  0.0000  0.0000  0.5000  1
]