data_[Na2Ta2Pb2Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Na  0.9300  1.8000  1.1600
  Ta  1.5000  1.4500  0.8200
  Pb  2.3300  1.8000  1.1225
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [P2_1/m]
_cell_length_a [7.1347]
_cell_length_b [7.3407]
_cell_length_c [8.4716]
_cell_angle_alpha [90.0000]
_cell_angle_beta [108.3360]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [NaTaPbSe4]
_chemical_formula_sum '[Na2 Ta2 Pb2 Se8]'
_cell_volume [421.1646]
_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
[
  Na  Na0  2  0.2283  0.2500  0.5501  1.0
  Ta  Ta1  2  0.2421  0.7500  0.3103  1.0
  Pb  Pb2  2  0.2184  0.2500  0.0526  1.0
  Se  Se3  4  0.0077  0.0050  0.2402  1.0
  Se  Se4  2  0.4205  0.7500  0.5989  1.0
  Se  Se5  2  0.4358  0.7500  0.1259  1.0
]