data_Mg2Hg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.54
_cell_length_b   12.54
_cell_length_c   12.54
_cell_angle_alpha   164.58
_cell_angle_beta   164.58
_cell_angle_gamma   21.87
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2Hg
_chemical_formula_sum   'Mg4 Hg2'
_cell_volume   139.23
_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
  Mg  Mg2  1  0.68  0.0  0.37  1.0
  Mg  Mg3  1  0.68  0.0  0.94  1.0
  Mg  Mg4  1  0.0  0.0  0.52  1.0
  Mg  Mg5  1  0.0  0.0  0.1  1.0
  Hg  Hg0  1  0.0  0.68  0.15  1.0
  Hg  Hg1  1  0.0  0.0  0.0  1.0

data_Mg2Hg
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.36
_cell_length_b   3.36
_cell_length_c   12.54
_cell_angle_alpha   97.71
_cell_angle_beta   97.71
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2Hg
_chemical_formula_sum   'Mg4 Hg2'
_cell_volume   139.23
_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
  Mg  Mg0  1  0.1  0.1  0.1  1.0
  Mg  Mg1  1  0.37  0.68  0.68  1.0
  Mg  Mg2  1  0.52  0.52  0.52  1.0
  Mg  Mg3  1  0.94  0.26  0.26  1.0
  Hg  Hg4  1  0.0  0.0  0.0  1.0
  Hg  Hg5  1  0.47  0.15  0.47  1.0

Mg Mg Mg Mg Hg Hg