data_HgSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.45
_cell_length_b   7.27
_cell_length_c   4.24
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgSe2
_chemical_formula_sum   'Hg2 Se4'
_cell_volume   167.69
_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  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.72  0.63  0.12  1.0
  Se  Se2  1  0.97  0.33  0.0  1.0
  Se  Se3  1  0.48  0.94  0.0  1.0
  Se  Se4  1  0.69  0.57  0.12  1.0
  Se  Se5  1  0.76  0.7  0.12  1.0

data_HgSe2
_symmetry_space_group_name_H-M   P1
_cell_length_a   4.24
_cell_length_b   5.45
_cell_length_c   7.27
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgSe2
_chemical_formula_sum   'Hg2 Se4'
_cell_volume   167.69
_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  1  0.0  0.0  0.0  1.0
  Hg  Hg1  1  0.12  0.72  0.63  1.0
  Se  Se2  1  -0.0  0.97  0.33  1.0
  Se  Se3  1  -0.0  0.48  0.94  1.0
  Se  Se4  1  0.12  0.69  0.57  1.0
  Se  Se5  1  0.12  0.76  0.7  1.0

Hg Hg Se Se Se Se
Hg Hg Se Se Se Se 0 5 - - o 0 3 - - o 0 3 o - o 0 2 - o o 1 4 o o o 1 5 o o o 1 2 o o o 1 3 o o o 2 4 o o o 3 5 o o o 3 4 o o o 