data_[Na4Sr4Nb4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Sr  0.9500  2.0000  1.3200
  Nb  1.6000  1.4500  0.8200
]
_symmetry_space_group_name_H-M [Amm2]
_cell_length_a [3.4680]
_cell_length_b [6.1024]
_cell_length_c [18.4550]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [38]
_chemical_formula_structural [NaSrNb]
_chemical_formula_sum '[Na4 Sr4 Nb4]'
_cell_volume [390.5608]
_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  2  0.0000  0.0000  0.1582  1
  Na  Na1  2  0.0000  0.0000  0.5492  1
  Sr  Sr2  2  0.5000  0.0000  0.3753  1
  Sr  Sr3  2  0.5000  0.0000  0.7435  1
  Nb  Nb4  2  0.0000  0.0000  0.9016  1
  Nb  Nb5  2  0.5000  0.0000  0.0011  1
]