data_Mg2AsPb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.74
_cell_length_b   3.74
_cell_length_c   6.98
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Mg2AsPb
_chemical_formula_sum   'Mg2 As1 Pb1'
_cell_volume   97.67
_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  0.87  0.87  0.57  1.0
  Mg  Mg2  1  0.0  0.0  0.6  1.0
  As  As0  1  0.0  0.0  0.87  1.0
  Pb  Pb3  1  0.87  0.87  0.41  1.0

data_Mg2AsPb
_symmetry_space_group_name_H-M   Cm
_cell_length_a   5.29
_cell_length_b   5.29
_cell_length_c   6.98
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Mg2AsPb
_chemical_formula_sum   'Mg4 As2 Pb2'
_cell_volume   195.34
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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  2  0.0  0.0  0.6  1.0
  Mg  Mg1  2  0.37  0.5  0.57  1.0
  As  As2  2  0.0  0.0  0.87  1.0
  Pb  Pb3  2  0.37  0.5  0.41  1.0

Mg Mg As Pb
Mg Mg As Pb 0 1 + + o 0 2 + + o 0 3 o o o 1 2 o o o 