data_[Nb2Al4Si4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Nb  1.6000  1.4500  0.8200
  Al  1.6100  1.2500  0.6750
  Si  1.9000  1.1000  0.5400
]
_symmetry_space_group_name_H-M [I4/mmm]
_cell_length_a [3.4114]
_cell_length_b [3.4114]
_cell_length_c [13.4358]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [139]
_chemical_formula_structural [Nb(AlSi)2]
_chemical_formula_sum '[Nb2 Al4 Si4]'
_cell_volume [156.3651]
_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
[
  Nb  Nb0  2  0.0000  0.0000  0.0000  1
  Al  Al1  4  0.0000  0.0000  0.2006  1
  Si  Si2  4  0.0000  0.0000  0.4042  1
]