data_[Na3Sm6Ta3O18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Sm  1.1700  1.8500  1.2290
  Ta  1.5000  1.4500  0.8200
  O  3.4400  0.6000  1.2600
]
_symmetry_space_group_name_H-M [R3]
_cell_length_a [5.7746]
_cell_length_b [5.7746]
_cell_length_c [15.0053]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [146]
_chemical_formula_structural [NaSm2TaO6]
_chemical_formula_sum '[Na3 Sm6 Ta3 O18]'
_cell_volume [433.3257]
_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
[
  Na  Na0  3  0.0000  0.0000  0.1971  1.0
  Sm  Sm1  3  0.0000  0.0000  0.4713  1.0
  Sm  Sm2  3  0.0000  0.0000  0.9733  1.0
  Ta  Ta3  3  0.0000  0.0000  0.6827  1.0
  O  O4  9  0.0160  0.3875  0.4129  1.0
  O  O5  9  0.0654  0.6671  0.2584  1.0
]