data_NiPb2Br
_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   NiPb2Br
_chemical_formula_sum   'Ni1 Pb2 Br1'
_cell_volume   99.09
_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
  Ni  Ni1  1  0.0  0.0  0.0  1.0
  Pb  Pb2  1  0.84  0.84  0.84  1.0
  Pb  Pb3  1  0.51  0.51  0.51  1.0
  Br  Br0  1  0.67  0.67  0.67  1.0

data_NiPb2Br
_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   NiPb2Br
_chemical_formula_sum   'Ni3 Pb6 Br3'
_cell_volume   297.28
_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
  Ni  Ni0  3  0.0  0.0  0.0  1.0
  Pb  Pb1  3  0.0  0.0  0.16  1.0
  Pb  Pb2  3  0.0  0.0  0.49  1.0
  Br  Br3  3  0.0  0.0  0.33  1.0

Ni Pb Pb Br
Ni Pb Pb Br 0 1 - - - 1 3 o o o 2 3 o o o 
NiPb2Br crystallizes in the trigonal R3m space group. Ni(1) is bonded to one Pb(1) and three equivalent Br(1) atoms to form NiPbBr3 trigonal pyramids that share  a cornercorner with one Br(1)Ni3Pb2 trigonal bipyramid and corners with six equivalent Ni(1)PbBr3 trigonal pyramids. The Ni(1)-Pb(1) bond length is 2.08 Å. All Ni(1)-Br(1) bond lengths are 3.00 Å. There are two inequivalent Pb sites. In the first Pb site, Pb(1) is bonded in a linear geometry to one Ni(1) and one Br(1) atom. The Pb(1)-Br(1) bond length is 2.08 Å. In the second Pb site, Pb(2) is bonded in a single-bond geometry to one Br(1) atom. The Pb(2)-Br(1) bond length is 2.08 Å. Br(1) is bonded to three equivalent Ni(1), one Pb(1), and one Pb(2) atom to form distorted BrNi3Pb2 trigonal bipyramids that share corners with six equivalent Br(1)Ni3Pb2 trigonal bipyramids and  a cornercorner with one Ni(1)PbBr3 trigonal pyramid.