data_CuNi5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.23
_cell_length_b   4.23
_cell_length_c   3.98
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   CuNi5
_chemical_formula_sum   'Cu1 Ni5'
_cell_volume   61.63
_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  0.0  0.0  0.0  1.0
  Ni  Ni1  1  0.11  0.22  0.0  1.0
  Ni  Ni2  1  0.0  0.44  0.0  1.0
  Ni  Ni3  1  0.41  0.0  0.99  1.0
  Ni  Ni4  1  0.3  0.22  0.99  1.0
  Ni  Ni5  1  0.41  0.44  0.99  1.0

data_CuNi5
_symmetry_space_group_name_H-M   Pm
_cell_length_a   4.23
_cell_length_b   3.98
_cell_length_c   4.23
_cell_angle_alpha   90.0
_cell_angle_beta   120.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   6
_chemical_formula_structural   CuNi5
_chemical_formula_sum   'Cu1 Ni5'
_cell_volume   61.63
_cell_formula_units_Z   1
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  1  0.0  0.0  0.0  1.0
  Ni  Ni1  1  0.0  0.0  0.44  1.0
  Ni  Ni2  1  0.11  0.0  0.22  1.0
  Ni  Ni3  1  0.3  0.0  0.22  1.0
  Ni  Ni4  1  0.41  0.0  0.44  1.0
  Ni  Ni5  1  0.41  0.0  0.0  1.0

Cu Ni Ni Ni Ni Ni
Cu Ni Ni Ni Ni Ni 0 1 o o o 1 4 o o - 1 2 o o o 3 4 o o o 4 5 o o o 
Ni5Cu is Hg_xSn structured and crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of one Ni5Cu cluster. There are five inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 4-coordinate geometry to one Ni(2), one Ni(4), one Ni(5), and one Cu(1) atom. The Ni(1)-Ni(2) bond length is 1.24 Å. The Ni(1)-Ni(4) bond length is 0.77 Å. The Ni(1)-Ni(5) bond length is 1.12 Å. The Ni(1)-Cu(1) bond length is 0.81 Å. In the second Ni site, Ni(2) is bonded in a distorted single-bond geometry to one Ni(1) atom. In the third Ni site, Ni(3) is bonded in a distorted single-bond geometry to one Ni(4) atom. The Ni(3)-Ni(4) bond length is 1.24 Å. In the fourth Ni site, Ni(4) is bonded in a 4-coordinate geometry to one Ni(1), one Ni(3), one Ni(5), and one Cu(1) atom. The Ni(4)-Ni(5) bond length is 0.81 Å. The Ni(4)-Cu(1) bond length is 1.12 Å. In the fifth Ni site, Ni(5) is bonded in a distorted single-bond geometry to one Ni(1) and one Ni(4) atom. Cu(1) is bonded in a distorted single-bond geometry to one Ni(1) and one Ni(4) atom.