data_[Sm6Hg2Se4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Sm  1.1700  1.8500  1.2290
  Hg  2.0000  1.5000  1.2450
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Immm]
_cell_length_a [4.1267]
_cell_length_b [6.0292]
_cell_length_c [13.0986]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [71]
_chemical_formula_structural [Sm3HgSe2]
_chemical_formula_sum '[Sm6 Hg2 Se4]'
_cell_volume [325.9042]
_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
[
  Sm  Sm0  4  0.0000  0.0000  0.1760  1
  Sm  Sm1  2  0.0000  0.0000  0.5000  1
  Hg  Hg2  2  0.0000  0.5000  0.5000  1
  Se  Se3  4  0.0000  0.5000  0.1640  1
]