data_MgMoPb2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.19
_cell_length_b   5.19
_cell_length_c   5.19
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   MgMoPb2
_chemical_formula_sum   'Mg1 Mo1 Pb2'
_cell_volume   98.93
_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  0.0  0.0  0.0  1.0
  Mo  Mo1  1  0.51  0.51  0.51  1.0
  Pb  Pb2  1  0.67  0.67  0.67  1.0
  Pb  Pb3  1  0.84  0.84  0.84  1.0

data_MgMoPb2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.19
_cell_length_b   5.19
_cell_length_c   12.72
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   MgMoPb2
_chemical_formula_sum   'Mg3 Mo3 Pb6'
_cell_volume   296.78
_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
  Mo  Mo1  3  0.0  0.0  0.49  1.0
  Pb  Pb2  3  0.0  0.0  0.16  1.0
  Pb  Pb3  3  0.0  0.0  0.33  1.0

Mg Mo Pb Pb
Mg Mo Pb Pb 0 3 - - - 1 2 o o o 2 3 o o o 
MgMoPb2 crystallizes in the trigonal R3m space group. Mg(1) is bonded to one Pb(2) and three equivalent Pb(1) atoms to form distorted MgPb4 trigonal pyramids that share  a cornercorner with one Pb(1)Mg3MoPb trigonal bipyramid, corners with six equivalent Mg(1)Pb4 trigonal pyramids, and edges with three equivalent Mo(1)Pb4 trigonal pyramids. The Mg(1)-Pb(2) bond length is 2.09 Å. All Mg(1)-Pb(1) bond lengths are 3.00 Å. Mo(1) is bonded to one Pb(1) and three equivalent Pb(2) atoms to form distorted MoPb4 trigonal pyramids that share corners with three equivalent Pb(1)Mg3MoPb trigonal bipyramids, corners with six equivalent Mo(1)Pb4 trigonal pyramids, and edges with three equivalent Mg(1)Pb4 trigonal pyramids. The Mo(1)-Pb(1) bond length is 2.09 Å. All Mo(1)-Pb(2) bond lengths are 3.00 Å. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded to three equivalent Mg(1), one Mo(1), and one Pb(2) atom to form PbMg3MoPb trigonal bipyramids that share corners with six equivalent Pb(1)Mg3MoPb trigonal bipyramids,  a cornercorner with one Mg(1)Pb4 trigonal pyramid, and corners with three equivalent Mo(1)Pb4 trigonal pyramids. The Pb(1)-Pb(2) bond length is 2.09 Å. In the second Pb site, Pb(2) is bonded in a distorted single-bond geometry to one Mg(1), three equivalent Mo(1), and one Pb(1) atom.