data_Cu3Ni
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.52
_cell_length_b   3.52
_cell_length_c   7.04
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Cu3Ni
_chemical_formula_sum   'Cu6 Ni2'
_cell_volume   87.23
_cell_formula_units_Z   2
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  0.64  0.76  0.16  1.0
  Cu  Cu1  1  0.88  0.76  0.88  1.0
  Cu  Cu2  1  0.64  0.76  0.64  1.0
  Cu  Cu3  1  0.88  0.76  0.4  1.0
  Cu  Cu4  1  0.88  0.0  0.16  1.0
  Cu  Cu5  1  0.64  0.0  0.88  1.0
  Ni  Ni6  1  0.88  0.0  0.64  1.0
  Ni  Ni7  1  0.64  0.0  0.4  1.0

data_Cu3Ni
_symmetry_space_group_name_H-M   P2
_cell_length_a   3.52
_cell_length_b   3.52
_cell_length_c   7.04
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   3
_chemical_formula_structural   Cu3Ni
_chemical_formula_sum   'Cu6 Ni2'
_cell_volume   87.23
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-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  2  0.38  0.0  0.86  1.0
  Cu  Cu1  2  0.38  0.76  0.14  1.0
  Cu  Cu2  2  0.38  0.76  0.62  1.0
  Ni  Ni3  2  0.38  0.0  0.38  1.0

Cu Cu Cu Cu Cu Cu Ni Ni
Cu Cu Cu Cu Cu Cu Ni Ni 0 4 o + o 1 5 o + o 2 6 o + o 3 7 o + o 
NiCu(Cu)2 crystallizes in the monoclinic P2 space group. The structure is zero-dimensional and consists of two Cu clusters and two NiCu clusters. In each Cu cluster, Cu(1,3) is bonded in a distorted single-bond geometry to one Cu(1,3) atom. The Cu(1,3)-Cu(1,3) bond length is 1.19 Å. In each NiCu cluster, Ni(1) is bonded in a single-bond geometry to one Cu(2) atom. The Ni(1)-Cu(2) bond length is 1.19 Å. Cu(2) is bonded in a single-bond geometry to one Ni(1) atom.