The compound described by Ir3Ni 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 Ni(1) atoms to form IrNi4Ir8 cuboctahedra that share corners with twelve equivalent Ir(1)Ni4Ir8 cuboctahedra, edges with eight equivalent Ir(1)Ni4Ir8 cuboctahedra, edges with eight equivalent Ir(2)Ni4Ir8 cuboctahedra, edges with eight equivalent Ni(1)Ir12 cuboctahedra, faces with four equivalent Ir(2)Ni4Ir8 cuboctahedra, faces with four equivalent Ni(1)Ir12 cuboctahedra, and faces with ten equivalent Ir(1)Ni4Ir8 cuboctahedra. In the second Ir site, Ir(2) is bonded to eight equivalent Ir(1) and four equivalent Ni(1) atoms to form IrNi4Ir8 cuboctahedra that share corners with four equivalent Ir(2)Ni4Ir8 cuboctahedra, corners with eight equivalent Ni(1)Ir12 cuboctahedra, edges with eight equivalent Ir(2)Ni4Ir8 cuboctahedra, edges with sixteen equivalent Ir(1)Ni4Ir8 cuboctahedra, faces with four equivalent Ir(2)Ni4Ir8 cuboctahedra, faces with six equivalent Ni(1)Ir12 cuboctahedra, and faces with eight equivalent Ir(1)Ni4Ir8 cuboctahedra. Ni(1) is bonded to four equivalent Ir(2) and eight equivalent Ir(1) atoms to form NiIr12 cuboctahedra that share corners with four equivalent Ni(1)Ir12 cuboctahedra, corners with eight equivalent Ir(2)Ni4Ir8 cuboctahedra, edges with eight equivalent Ni(1)Ir12 cuboctahedra, edges with sixteen equivalent Ir(1)Ni4Ir8 cuboctahedra, faces with four equivalent Ni(1)Ir12 cuboctahedra, faces with six equivalent Ir(2)Ni4Ir8 cuboctahedra, and faces with eight equivalent Ir(1)Ni4Ir8 cuboctahedra. is represented by the CIF file [CIF]
data_NiIr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.640
_cell_length_b   4.640
_cell_length_c   4.640
_cell_angle_alpha   132.167
_cell_angle_beta   132.167
_cell_angle_gamma   69.966
_symmetry_Int_Tables_number   1
_cell_volume   53.797
_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  Ni0  1  0.000  0.000  0.000  1.0
  Ir  Ir1  1  0.750  0.250  0.500  1.0
  Ir  Ir2  1  0.250  0.750  0.500  1.0
  Ir  Ir3  1  0.500  0.500  0.000  1.0
[/CIF]
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The compound described by Ir3Ni 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 Ni(1) atoms to form IrNi4Ir8 cuboctahedra that share corners with twelve equivalent Ir(1)Ni4Ir8 cuboctahedra, edges with eight equivalent Ir(1)Ni4Ir8 cuboctahedra, edges with eight equivalent Ir(2)Ni4Ir8 cuboctahedra, edges with eight equivalent Ni(1)Ir12 cuboctahedra, faces with four equivalent Ir(2)Ni4Ir8 cuboctahedra, faces with four equivalent Ni(1)Ir12 cuboctahedra, and faces with ten equivalent Ir(1)Ni4Ir8 cuboctahedra. In the second Ir site, Ir(2) is bonded to eight equivalent Ir(1) and four equivalent Ni(1) atoms to form IrNi4Ir8 cuboctahedra that share corners with four equivalent Ir(2)Ni4Ir8 cuboctahedra, corners with eight equivalent Ni(1)Ir12 cuboctahedra, edges with eight equivalent Ir(2)Ni4Ir8 cuboctahedra, edges with sixteen equivalent Ir(1)Ni4Ir8 cuboctahedra, faces with four equivalent Ir(2)Ni4Ir8 cuboctahedra, faces with six equivalent Ni(1)Ir12 cuboctahedra, and faces with eight equivalent Ir(1)Ni4Ir8 cuboctahedra. Ni(1) is bonded to four equivalent Ir(2) and eight equivalent Ir(1) atoms to form NiIr12 cuboctahedra that share corners with four equivalent Ni(1)Ir12 cuboctahedra, corners with eight equivalent Ir(2)Ni4Ir8 cuboctahedra, edges with eight equivalent Ni(1)Ir12 cuboctahedra, edges with sixteen equivalent Ir(1)Ni4Ir8 cuboctahedra, faces with four equivalent Ni(1)Ir12 cuboctahedra, faces with six equivalent Ir(2)Ni4Ir8 cuboctahedra, and faces with eight equivalent Ir(1)Ni4Ir8 cuboctahedra. is represented by the CIF file [CIF]
data_NiIr3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.640
_cell_length_b   4.640
_cell_length_c   4.640
_cell_angle_alpha   132.167
_cell_angle_beta   132.167
_cell_angle_gamma   69.966
_symmetry_Int_Tables_number   1
_cell_volume   53.797
_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  Ni0  1  0.000  0.000  0.000  1.0
  Ir  Ir1  1  0.750  0.250  0.500  1.0
  Ir  Ir2  1  0.250  0.750  0.500  1.0
  Ir  Ir3  1  0.500  0.500  0.000  1.0
[/CIF]
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