data_[Na4Sr8O4]
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
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [Cmme]
_cell_length_a [6.4080]
_cell_length_b [14.1149]
_cell_length_c [6.6342]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [67]
_chemical_formula_structural [NaSr2O]
_chemical_formula_sum '[Na4 Sr8 O4]'
_cell_volume [600.0535]
_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  4  0.0000  0.2500  0.6809  1.0
  Sr  Sr1  8  0.0000  0.0844  0.1921  1.0
  O  O2  4  0.2500  0.0000  0.0000  1.0
]