data_[Ce6Ag18Se18]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Ce  1.1200  1.8500  1.0800
  Ag  1.9300  1.6000  1.0867
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [R-3]
_cell_length_a [7.6015]
_cell_length_b [7.6015]
_cell_length_c [21.0764]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [120.0000]
_symmetry_Int_Tables_number [148]
_chemical_formula_structural [Ce(AgSe)3]
_chemical_formula_sum '[Ce6 Ag18 Se18]'
_cell_volume [1054.6950]
_cell_formula_units_Z [6]
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
[
  Ce  Ce0  6  0.0000  0.0000  0.3335  1.0
  Ag  Ag1  18  0.0026  0.3440  0.8747  1.0
  Se  Se2  18  0.0000  0.3326  0.7422  1.0
]