data_Al4CuNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.06
_cell_length_b   5.06
_cell_length_c   5.06
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Al4CuNi
_chemical_formula_sum   'Al4 Cu1 Ni1'
_cell_volume   91.43
_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
  Al  Al0  1  0.47  0.47  0.68  1.0
  Al  Al1  1  0.47  0.68  0.47  1.0
  Al  Al2  1  0.68  0.47  0.47  1.0
  Al  Al3  1  0.68  0.68  0.68  1.0
  Cu  Cu4  1  0.36  0.36  0.36  1.0
  Ni  Ni5  1  0.0  0.0  0.0  1.0

data_Al4CuNi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.06
_cell_length_b   5.06
_cell_length_c   12.39
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Al4CuNi
_chemical_formula_sum   'Al12 Cu3 Ni3'
_cell_volume   274.29
_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
  Al  Al0  9  0.07  0.14  0.46  1.0
  Al  Al1  3  0.0  0.0  0.32  1.0
  Cu  Cu2  3  0.0  0.0  0.64  1.0
  Ni  Ni3  3  0.0  0.0  0.0  1.0

Al Al Al Al Cu Ni
Al Al Al Al Cu Ni 0 2 o o o 0 1 o o o 0 3 o o o 0 4 o o o 0 5 + o + 0 5 o + + 0 5 o o + 1 2 o o o 1 3 o o o 1 4 o o o 1 5 + + o 1 5 o + + 1 5 o + o 2 3 o o o 2 4 o o o 2 5 + + o 2 5 + o + 2 5 + o o 3 5 + + o 3 5 + o + 3 5 o + + 4 5 + o o 4 5 o + o 4 5 o o + 
NiCuAl4 crystallizes in the trigonal R3m space group. Ni(1) is bonded in a 12-coordinate geometry to three equivalent Cu(1), three equivalent Al(2), and six equivalent Al(1) atoms. All Ni(1)-Cu(1) bond lengths are 2.94 Å. All Ni(1)-Al(2) bond lengths are 2.92 Å. All Ni(1)-Al(1) bond lengths are 3.09 Å. Cu(1) is bonded to three equivalent Ni(1), three equivalent Al(2), and six equivalent Al(1) atoms to form a mixture of distorted corner and edge-sharing CuAl9Ni3 cuboctahedra. All Cu(1)-Al(2) bond lengths are 2.93 Å. There are three shorter (2.28 Å) and three longer (3.01 Å) Cu(1)-Al(1) bond lengths. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded in a 2-coordinate geometry to two equivalent Ni(1), two equivalent Cu(1), one Al(2), and two equivalent Al(1) atoms. The Al(1)-Al(2) bond length is 1.84 Å. Both Al(1)-Al(1) bond lengths are 1.06 Å. In the second Al site, Al(2) is bonded in a distorted q6 geometry to three equivalent Ni(1), three equivalent Cu(1), and three equivalent Al(1) atoms.