data_HgSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.0
_cell_length_b   7.0
_cell_length_c   3.87
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgSe
_chemical_formula_sum   'Hg3 Se3'
_cell_volume   163.8
_cell_formula_units_Z   3
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  0.5  0.02  0.93  1.0
  Hg  Hg2  1  0.0  0.04  0.93  1.0
  Se  Se3  1  0.68  0.28  0.0  1.0
  Se  Se4  1  0.18  0.77  0.0  1.0
  Se  Se5  1  0.64  0.0  0.0  1.0

data_HgSe
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.87
_cell_length_b   7.0
_cell_length_c   7.0
_cell_angle_alpha   120.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgSe
_chemical_formula_sum   'Hg3 Se3'
_cell_volume   163.8
_cell_formula_units_Z   3
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  0.93  0.0  0.04  1.0
  Hg  Hg2  1  0.93  0.5  0.02  1.0
  Se  Se3  1  0.0  0.68  0.28  1.0
  Se  Se4  1  0.0  0.18  0.77  1.0
  Se  Se5  1  0.0  0.64  0.0  1.0

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