data_MgBiPb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.3
_cell_length_b   5.3
_cell_length_c   5.3
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgBiPb
_chemical_formula_sum   'Mg1 Bi1 Pb1'
_cell_volume   105.1
_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  0.0  0.0  0.0  1.0
  Bi  Bi0  1  0.62  0.62  0.62  1.0
  Pb  Pb2  1  0.75  0.75  0.75  1.0

data_MgBiPb
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.3
_cell_length_b   5.3
_cell_length_c   12.98
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   MgBiPb
_chemical_formula_sum   'Mg3 Bi3 Pb3'
_cell_volume   315.29
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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  3  0.0  0.0  0.0  1.0
  Bi  Bi1  3  0.0  0.0  0.38  1.0
  Pb  Pb2  3  0.0  0.0  0.25  1.0

Mg Bi Pb
Mg Bi Pb 0 2 - - - 0 2 - - o 0 2 - o - 0 2 o - - 0 1 - - o 0 1 - o - 0 1 o - - 1 2 o o o 
MgPbBi crystallizes in the trigonal R3m space group. Mg(1) is bonded to four equivalent Pb(1) and three equivalent Bi(1) atoms to form a mixture of distorted corner and edge-sharing MgBi3Pb4 hexagonal pyramids. There are three shorter (3.23 Å) and one longer (3.30 Å) Mg(1)-Pb(1) bond length. All Mg(1)-Bi(1) bond lengths are 3.12 Å. Pb(1) is bonded in a distorted single-bond geometry to four equivalent Mg(1) and one Bi(1) atom. The Pb(1)-Bi(1) bond length is 1.65 Å. Bi(1) is bonded in a distorted single-bond geometry to three equivalent Mg(1) and one Pb(1) atom.