The compound described by Ni3Cu is Copper-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Ni(1), four equivalent Ni(2), and four equivalent Cu(1) atoms to form NiCu4Ni8 cuboctahedra that share corners with twelve equivalent Ni(1)Cu4Ni8 cuboctahedra, edges with eight equivalent Ni(1)Cu4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Cu4Ni8 cuboctahedra, edges with eight equivalent Cu(1)Ni12 cuboctahedra, faces with four equivalent Ni(2)Cu4Ni8 cuboctahedra, faces with four equivalent Cu(1)Ni12 cuboctahedra, and faces with ten equivalent Ni(1)Cu4Ni8 cuboctahedra. In the second Ni site, Ni(2) is bonded to eight equivalent Ni(1) and four equivalent Cu(1) atoms to form NiCu4Ni8 cuboctahedra that share corners with four equivalent Ni(2)Cu4Ni8 cuboctahedra, corners with eight equivalent Cu(1)Ni12 cuboctahedra, edges with eight equivalent Ni(2)Cu4Ni8 cuboctahedra, edges with sixteen equivalent Ni(1)Cu4Ni8 cuboctahedra, faces with four equivalent Ni(2)Cu4Ni8 cuboctahedra, faces with six equivalent Cu(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(1)Cu4Ni8 cuboctahedra. Cu(1) is bonded to four equivalent Ni(2) and eight equivalent Ni(1) atoms to form CuNi12 cuboctahedra that share corners with four equivalent Cu(1)Ni12 cuboctahedra, corners with eight equivalent Ni(2)Cu4Ni8 cuboctahedra, edges with eight equivalent Cu(1)Ni12 cuboctahedra, edges with sixteen equivalent Ni(1)Cu4Ni8 cuboctahedra, faces with four equivalent Cu(1)Ni12 cuboctahedra, faces with six equivalent Ni(2)Cu4Ni8 cuboctahedra, and faces with eight equivalent Ni(1)Cu4Ni8 cuboctahedra. is represented by the CIF file [CIF]
data_CuNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.267
_cell_length_b   4.267
_cell_length_c   4.267
_cell_angle_alpha   131.387
_cell_angle_beta   131.387
_cell_angle_gamma   71.199
_symmetry_Int_Tables_number   1
_cell_volume   42.800
_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
  Cu  Cu0  1  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.750  0.250  0.500  1.0
  Ni  Ni2  1  0.250  0.750  0.500  1.0
  Ni  Ni3  1  0.500  0.500  0.000  1.0
[/CIF]
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The compound described by Ni3Cu is Copper-derived structured and crystallizes in the tetragonal I4/mmm space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded to four equivalent Ni(1), four equivalent Ni(2), and four equivalent Cu(1) atoms to form NiCu4Ni8 cuboctahedra that share corners with twelve equivalent Ni(1)Cu4Ni8 cuboctahedra, edges with eight equivalent Ni(1)Cu4Ni8 cuboctahedra, edges with eight equivalent Ni(2)Cu4Ni8 cuboctahedra, edges with eight equivalent Cu(1)Ni12 cuboctahedra, faces with four equivalent Ni(2)Cu4Ni8 cuboctahedra, faces with four equivalent Cu(1)Ni12 cuboctahedra, and faces with ten equivalent Ni(1)Cu4Ni8 cuboctahedra. In the second Ni site, Ni(2) is bonded to eight equivalent Ni(1) and four equivalent Cu(1) atoms to form NiCu4Ni8 cuboctahedra that share corners with four equivalent Ni(2)Cu4Ni8 cuboctahedra, corners with eight equivalent Cu(1)Ni12 cuboctahedra, edges with eight equivalent Ni(2)Cu4Ni8 cuboctahedra, edges with sixteen equivalent Ni(1)Cu4Ni8 cuboctahedra, faces with four equivalent Ni(2)Cu4Ni8 cuboctahedra, faces with six equivalent Cu(1)Ni12 cuboctahedra, and faces with eight equivalent Ni(1)Cu4Ni8 cuboctahedra. Cu(1) is bonded to four equivalent Ni(2) and eight equivalent Ni(1) atoms to form CuNi12 cuboctahedra that share corners with four equivalent Cu(1)Ni12 cuboctahedra, corners with eight equivalent Ni(2)Cu4Ni8 cuboctahedra, edges with eight equivalent Cu(1)Ni12 cuboctahedra, edges with sixteen equivalent Ni(1)Cu4Ni8 cuboctahedra, faces with four equivalent Cu(1)Ni12 cuboctahedra, faces with six equivalent Ni(2)Cu4Ni8 cuboctahedra, and faces with eight equivalent Ni(1)Cu4Ni8 cuboctahedra. is represented by the CIF file [CIF]
data_CuNi3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.267
_cell_length_b   4.267
_cell_length_c   4.267
_cell_angle_alpha   131.387
_cell_angle_beta   131.387
_cell_angle_gamma   71.199
_symmetry_Int_Tables_number   1
_cell_volume   42.800
_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
  Cu  Cu0  1  0.000  0.000  0.000  1.0
  Ni  Ni1  1  0.750  0.250  0.500  1.0
  Ni  Ni2  1  0.250  0.750  0.500  1.0
  Ni  Ni3  1  0.500  0.500  0.000  1.0
[/CIF]
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