data_HgAs2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.41
_cell_length_b   6.41
_cell_length_c   6.72
_cell_angle_alpha   116.95
_cell_angle_beta   116.95
_cell_angle_gamma   26.69
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgAs2Se
_chemical_formula_sum   'Hg1 As2 Se1'
_cell_volume   109.69
_cell_formula_units_Z   1
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  Hg2  1  0.67  0.0  0.97  1.0
  As  As0  1  0.8  0.0  0.09  1.0
  As  As1  1  0.54  0.0  0.85  1.0
  Se  Se3  1  0.0  0.0  0.0  1.0

data_HgAs2Se
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.96
_cell_length_b   6.41
_cell_length_c   6.72
_cell_angle_alpha   116.95
_cell_angle_beta   90.0
_cell_angle_gamma   103.34
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HgAs2Se
_chemical_formula_sum   'Hg1 As2 Se1'
_cell_volume   109.69
_cell_formula_units_Z   1
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  0.33  0.03  1.0
  As  As1  1  0.0  0.2  0.91  1.0
  As  As2  1  0.0  0.46  0.15  1.0
  Se  Se3  1  0.0  0.0  0.0  1.0

Hg As As Se
Hg As As Se 0 2 o o o 0 1 o o + 1 3 + o o 