data_Hg2AsSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.76
_cell_length_b   6.4
_cell_length_c   5.67
_cell_angle_alpha   90.0
_cell_angle_beta   90.18
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Hg2AsSe
_chemical_formula_sum   'Hg2 As1 Se1'
_cell_volume   100.19
_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  Hg1  1  0.15  0.2  0.25  1.0
  Hg  Hg2  1  0.59  0.2  0.41  1.0
  As  As0  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.99  0.0  0.83  1.0

data_Hg2AsSe
_symmetry_space_group_name_H-M   P1
_cell_length_a   2.76
_cell_length_b   5.67
_cell_length_c   6.4
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.18
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Hg2AsSe
_chemical_formula_sum   'Hg2 As1 Se1'
_cell_volume   100.19
_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  0.41  0.59  0.8  1.0
  Hg  Hg1  1  0.85  0.75  0.8  1.0
  As  As2  1  0.0  0.0  0.0  1.0
  Se  Se3  1  0.01  0.17  0.0  1.0

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