The material described by Ir3Pb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to four equivalent Ir(1), four equivalent Ir(2), and four equivalent Pb(1) atoms to form IrIr8Pb4 cuboctahedra that share corners with twelve equivalent Ir(1)Ir8Pb4 cuboctahedra, edges with eight equivalent Ir(1)Ir8Pb4 cuboctahedra, edges with eight equivalent Ir(2)Ir8Pb4 cuboctahedra, edges with eight equivalent Pb(1)Ir12 cuboctahedra, faces with four equivalent Ir(2)Ir8Pb4 cuboctahedra, faces with four equivalent Pb(1)Ir12 cuboctahedra, and faces with ten equivalent Ir(1)Ir8Pb4 cuboctahedra. In the second Ir site, Ir(2) is bonded to eight equivalent Ir(1) and four equivalent Pb(1) atoms to form IrIr8Pb4 cuboctahedra that share corners with four equivalent Ir(2)Ir8Pb4 cuboctahedra, corners with eight equivalent Pb(1)Ir12 cuboctahedra, edges with eight equivalent Ir(2)Ir8Pb4 cuboctahedra, edges with sixteen equivalent Ir(1)Ir8Pb4 cuboctahedra, faces with four equivalent Ir(2)Ir8Pb4 cuboctahedra, faces with six equivalent Pb(1)Ir12 cuboctahedra, and faces with eight equivalent Ir(1)Ir8Pb4 cuboctahedra. Pb(1) is bonded to four equivalent Ir(2) and eight equivalent Ir(1) atoms to form PbIr12 cuboctahedra that share corners with four equivalent Pb(1)Ir12 cuboctahedra, corners with eight equivalent Ir(2)Ir8Pb4 cuboctahedra, edges with eight equivalent Pb(1)Ir12 cuboctahedra, edges with sixteen equivalent Ir(1)Ir8Pb4 cuboctahedra, faces with four equivalent Pb(1)Ir12 cuboctahedra, faces with six equivalent Ir(2)Ir8Pb4 cuboctahedra, and faces with eight equivalent Ir(1)Ir8Pb4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ir3Pb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.882
_cell_length_b   4.882
_cell_length_c   4.882
_cell_angle_alpha   130.051
_cell_angle_beta   130.051
_cell_angle_gamma   73.325
_symmetry_Int_Tables_number   1
_cell_volume   66.552
_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
  Ir  Ir0  1  0.750  0.250  0.500  1.0
  Ir  Ir1  1  0.250  0.750  0.500  1.0
  Ir  Ir2  1  0.500  0.500  0.000  1.0
  Pb  Pb3  1  0.000  0.000  0.000  1.0
[/CIF]
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The material described by Ir3Pb is beta Cu3Ti-like structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ir sites. In the first Ir site, Ir(1) is bonded to four equivalent Ir(1), four equivalent Ir(2), and four equivalent Pb(1) atoms to form IrIr8Pb4 cuboctahedra that share corners with twelve equivalent Ir(1)Ir8Pb4 cuboctahedra, edges with eight equivalent Ir(1)Ir8Pb4 cuboctahedra, edges with eight equivalent Ir(2)Ir8Pb4 cuboctahedra, edges with eight equivalent Pb(1)Ir12 cuboctahedra, faces with four equivalent Ir(2)Ir8Pb4 cuboctahedra, faces with four equivalent Pb(1)Ir12 cuboctahedra, and faces with ten equivalent Ir(1)Ir8Pb4 cuboctahedra. In the second Ir site, Ir(2) is bonded to eight equivalent Ir(1) and four equivalent Pb(1) atoms to form IrIr8Pb4 cuboctahedra that share corners with four equivalent Ir(2)Ir8Pb4 cuboctahedra, corners with eight equivalent Pb(1)Ir12 cuboctahedra, edges with eight equivalent Ir(2)Ir8Pb4 cuboctahedra, edges with sixteen equivalent Ir(1)Ir8Pb4 cuboctahedra, faces with four equivalent Ir(2)Ir8Pb4 cuboctahedra, faces with six equivalent Pb(1)Ir12 cuboctahedra, and faces with eight equivalent Ir(1)Ir8Pb4 cuboctahedra. Pb(1) is bonded to four equivalent Ir(2) and eight equivalent Ir(1) atoms to form PbIr12 cuboctahedra that share corners with four equivalent Pb(1)Ir12 cuboctahedra, corners with eight equivalent Ir(2)Ir8Pb4 cuboctahedra, edges with eight equivalent Pb(1)Ir12 cuboctahedra, edges with sixteen equivalent Ir(1)Ir8Pb4 cuboctahedra, faces with four equivalent Pb(1)Ir12 cuboctahedra, faces with six equivalent Ir(2)Ir8Pb4 cuboctahedra, and faces with eight equivalent Ir(1)Ir8Pb4 cuboctahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ir3Pb
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.882
_cell_length_b   4.882
_cell_length_c   4.882
_cell_angle_alpha   130.051
_cell_angle_beta   130.051
_cell_angle_gamma   73.325
_symmetry_Int_Tables_number   1
_cell_volume   66.552
_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
  Ir  Ir0  1  0.750  0.250  0.500  1.0
  Ir  Ir1  1  0.250  0.750  0.500  1.0
  Ir  Ir2  1  0.500  0.500  0.000  1.0
  Pb  Pb3  1  0.000  0.000  0.000  1.0
[/CIF]
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