data_[Hg8Se8]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Hg  2.0000  1.5000  1.2450
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [C2/m]
_cell_length_a [15.8250]
_cell_length_b [4.2779]
_cell_length_c [20.9922]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [12]
_chemical_formula_structural [HgSe]
_chemical_formula_sum '[Hg8 Se8]'
_cell_volume [1421.1053]
_cell_formula_units_Z [8]
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  4  0.0225  0.5000  0.3906  1
  Hg  Hg1  4  0.1377  0.0000  0.5298  1
  Se  Se2  4  0.0671  0.0000  0.6422  1
  Se  Se3  4  0.1640  0.5000  0.4549  1
]