data_ZnCuNi2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.0
_cell_length_b   4.0
_cell_length_c   4.0
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   ZnCuNi2
_chemical_formula_sum   'Zn1 Cu1 Ni2'
_cell_volume   45.15
_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
  Zn  Zn3  1  0.83  0.83  0.83  1.0
  Cu  Cu0  1  0.0  0.0  0.0  1.0
  Ni  Ni1  1  0.24  0.24  0.24  1.0
  Ni  Ni2  1  0.41  0.41  0.41  1.0

data_ZnCuNi2
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.0
_cell_length_b   4.0
_cell_length_c   9.79
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   ZnCuNi2
_chemical_formula_sum   'Zn3 Cu3 Ni6'
_cell_volume   135.44
_cell_formula_units_Z   3
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  '-y, x-y, z'
  3  '-x+y, -x, z'
  4  '-y, -x, z'
  5  '-x+y, y, z'
  6  'x, x-y, z'
  7  'x+1/3, y+2/3, z+2/3'
  8  '-y+1/3, x-y+2/3, z+2/3'
  9  '-x+y+1/3, -x+2/3, z+2/3'
  10  '-y+1/3, -x+2/3, z+2/3'
  11  '-x+y+1/3, y+2/3, z+2/3'
  12  'x+1/3, x-y+2/3, z+2/3'
  13  'x+2/3, y+1/3, z+1/3'
  14  '-y+2/3, x-y+1/3, z+1/3'
  15  '-x+y+2/3, -x+1/3, z+1/3'
  16  '-y+2/3, -x+1/3, z+1/3'
  17  '-x+y+2/3, y+1/3, z+1/3'
  18  'x+2/3, x-y+1/3, z+1/3'
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
  Zn  Zn0  3  0.0  0.0  0.17  1.0
  Cu  Cu1  3  0.0  0.0  0.0  1.0
  Ni  Ni2  3  0.0  0.0  0.59  1.0
  Ni  Ni3  3  0.0  0.0  0.76  1.0

Zn Cu Ni Ni
Zn Cu Ni Ni 0 1 + + + 2 3 o o o 
Ni2CuZn crystallizes in the trigonal R3m space group. There are two inequivalent Ni sites. In the first Ni site, Ni(1) is bonded in a 5-coordinate geometry to one Ni(2), one Cu(1), and three equivalent Zn(1) atoms. The Ni(1)-Ni(2) bond length is 1.70 Å. The Ni(1)-Cu(1) bond length is 2.34 Å. All Ni(1)-Zn(1) bond lengths are 2.44 Å. In the second Ni site, Ni(2) is bonded in a 4-coordinate geometry to one Ni(1) and three equivalent Zn(1) atoms. All Ni(2)-Zn(1) bond lengths are 2.44 Å. Cu(1) is bonded in a single-bond geometry to one Ni(1) and one Zn(1) atom. The Cu(1)-Zn(1) bond length is 1.70 Å. Zn(1) is bonded in a distorted single-bond geometry to three equivalent Ni(1), three equivalent Ni(2), and one Cu(1) atom.