data_Mg2SiHg
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.16
_cell_length_b   3.91
_cell_length_c   6.33
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2SiHg
_chemical_formula_sum   'Mg2 Si1 Hg1'
_cell_volume   78.23
_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
  Mg  Mg1  1  0.58  0.95  0.84  1.0
  Mg  Mg2  1  0.58  0.95  0.49  1.0
  Si  Si3  1  0.0  0.0  0.0  1.0
  Hg  Hg0  1  0.0  0.0  0.16  1.0

data_Mg2SiHg
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.16
_cell_length_b   3.91
_cell_length_c   6.33
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2SiHg
_chemical_formula_sum   'Mg2 Si1 Hg1'
_cell_volume   78.23
_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
  Mg  Mg0  1  0.58  0.95  0.49  1.0
  Mg  Mg1  1  0.58  0.95  0.84  1.0
  Si  Si2  1  0.0  0.0  0.0  1.0
  Hg  Hg3  1  0.0  0.0  0.16  1.0

Mg Mg Si Hg
Mg Mg Si Hg 0 2 + + + 0 1 o o o 1 3 + + o 2 3 o o o 