data_[Ca2Si2Pb2Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ca  1.0000  1.8000  1.1400
  Si  1.9000  1.1000  0.5400
  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 [6.9654]
_cell_length_b [6.9376]
_cell_length_c [8.2787]
_cell_angle_alpha [90.0000]
_cell_angle_beta [107.3711]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [11]
_chemical_formula_structural [CaSiPbSe4]
_chemical_formula_sum '[Ca2 Si2 Pb2 Se8]'
_cell_volume [381.8064]
_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
[
  Ca  Ca0  2  0.2502  0.7500  0.5613  1.0
  Si  Si1  2  0.2331  0.2500  0.3087  1.0
  Pb  Pb2  2  0.2293  0.7500  0.0639  1.0
  Se  Se3  4  0.0068  0.5018  0.2540  1.0
  Se  Se4  2  0.4092  0.2500  0.5875  1.0
  Se  Se5  2  0.4143  0.2500  0.1229  1.0
]