data_[Ba3Sr3Se6O18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ba  0.8900  2.1500  1.4900
  Sr  0.9500  2.0000  1.3200
  Se  2.5500  1.1500  1.0133
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [5.9112]
_cell_length_b [5.9112]
_cell_length_c [18.6418]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [BaSr(SeO3)2]
_chemical_formula_sum '[Ba3 Sr3 Se6 O18]'
_cell_volume [564.1202]
_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
[
  Ba  Ba0  3  0.0000  0.0000  0.0000  1.0
  Sr  Sr1  3  -0.0000  0.0000  0.5000  1.0
  Se  Se2  6  0.0000  0.0000  0.2084  1.0
  O  O3  18  0.0296  0.2809  0.2466  1.0
]