data_[Sm4Ag8Se12]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Sm  1.1700  1.8500  1.2290
  Ag  1.9300  1.6000  1.0867
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Cmcm]
_cell_length_a [8.6372]
_cell_length_b [12.9792]
_cell_length_c [5.3212]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [63]
_chemical_formula_structural [SmAg2Se3]
_chemical_formula_sum '[Sm4 Ag8 Se12]'
_cell_volume [596.5307]
_cell_formula_units_Z [4]
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
[
  Sm  Sm0  4  0.0000  0.2645  0.7500  1
  Ag  Ag1  8  0.2098  0.0000  0.0000  1
  Se  Se2  8  0.1926  0.3355  0.2500  1
  Se  Se3  4  0.0000  0.1305  0.2500  1
]