data_[Ac20Si8N4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ac  1.1000  1.9500  1.2600
  Si  1.9000  1.1000  0.5400
  N  3.0400  0.6500  0.6300
]
_symmetry_space_group_name_H-M [Cmcm]
_cell_length_a [6.1623]
_cell_length_b [13.0297]
_cell_length_c [13.9829]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [63]
_chemical_formula_structural [Ac5Si2N]
_chemical_formula_sum '[Ac20 Si8 N4]'
_cell_volume [1122.7305]
_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
[
  Ac  Ac0  8  0.0000  0.0573  0.1229  1
  Ac  Ac1  8  0.0000  0.3376  0.1042  1
  Ac  Ac2  4  0.0000  0.3057  0.7500  1
  Si  Si3  8  0.0000  0.1780  0.5689  1
  N  N4  4  0.0000  0.2043  0.2500  1
]