data_[Hg2Pb6Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Hg  2.0000  1.5000  1.2450
  Pb  2.3300  1.8000  1.1225
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Pmn2_1]
_cell_length_a [8.9668]
_cell_length_b [9.5546]
_cell_length_c [6.3055]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [31]
_chemical_formula_structural [HgPb3Se4]
_chemical_formula_sum '[Hg2 Pb6 Se8]'
_cell_volume [540.2227]
_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
[
  Hg  Hg0  2  0.0000  0.8148  0.9736  1.0
  Pb  Pb1  4  0.2227  0.3422  0.9454  1.0
  Pb  Pb2  2  0.0000  0.1223  0.4407  1.0
  Se  Se3  4  0.2395  0.3319  0.4186  1.0
  Se  Se4  2  0.0000  0.0980  0.9173  1.0
  Se  Se5  2  0.0000  0.7958  0.4252  1.0
]