data_[Hg4H8Se4]
loop_
 _atom_type_symbol
 _atom_type_electronegativity
 _atom_type_radius
 _atom_type_ionic_radius
[
  Hg  2.0000  1.5000  1.2450
  H  2.2000  0.2500  0.0000
  Se  2.5500  1.1500  1.0133
]
_symmetry_space_group_name_H-M [Fmmm]
_cell_length_a [5.7438]
_cell_length_b [6.3150]
_cell_length_c [7.2129]
_cell_angle_alpha [90.0000]
_cell_angle_beta [90.0000]
_cell_angle_gamma [90.0000]
_symmetry_Int_Tables_number [69]
_chemical_formula_structural [HgH2Se]
_chemical_formula_sum '[Hg4 H8 Se4]'
_cell_volume [261.6246]
_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
[
  Hg  Hg0  4  0.0000  0.0000  0.0000  1
  H  H1  8  0.0000  0.0000  0.2548  1
  Se  Se2  4  0.0000  0.0000  0.5000  1
]