data_Na2TiNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.82
_cell_length_b   4.82
_cell_length_c   4.82
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Na2TiNi
_chemical_formula_sum   'Na2 Ti1 Ni1'
_cell_volume   79.35
_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
  Na  Na0  1  0.71  0.71  0.71  1.0
  Na  Na1  1  0.12  0.12  0.12  1.0
  Ti  Ti3  1  0.0  0.0  0.0  1.0
  Ni  Ni2  1  0.41  0.41  0.41  1.0

data_Na2TiNi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   4.82
_cell_length_b   4.82
_cell_length_c   11.81
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   Na2TiNi
_chemical_formula_sum   'Na6 Ti3 Ni3'
_cell_volume   238.04
_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
  Na  Na0  3  0.0  0.0  0.29  1.0
  Na  Na1  3  0.0  0.0  0.88  1.0
  Ti  Ti2  3  0.0  0.0  0.0  1.0
  Ni  Ni3  3  0.0  0.0  0.59  1.0

Na Na Ti Ni
Na Na Ti Ni 0 3 o o + 0 3 o + o 0 3 + o o 0 2 o + + 0 2 + o + 0 2 + + o 0 1 o + + 0 1 + o + 0 1 + + o 1 2 o o o 1 3 o o - 1 3 o - o 1 3 - o o 2 3 o o - 2 3 o - o 2 3 - o o 
Na2TiNi is Heusler structured and crystallizes in the trigonal R3m space group. There are two inequivalent Na sites. In the first Na site, Na(1) is bonded in a 8-coordinate geometry to four equivalent Ti(1) and four equivalent Ni(1) atoms. There are three shorter (2.82 Å) and one longer (3.48 Å) Na(1)-Ti(1) bond length. There are three shorter (2.82 Å) and one longer (3.48 Å) Na(1)-Ni(1) bond length. In the second Na site, Na(2) is bonded in a single-bond geometry to one Ti(1) and four equivalent Ni(1) atoms. The Na(2)-Ti(1) bond length is 1.37 Å. There are three shorter (2.82 Å) and one longer (3.48 Å) Na(2)-Ni(1) bond length. Ti(1) is bonded in a single-bond geometry to one Na(2), four equivalent Na(1), and three equivalent Ni(1) atoms. All Ti(1)-Ni(1) bond lengths are 2.93 Å. Ni(1) is bonded in a 11-coordinate geometry to four equivalent Na(1), four equivalent Na(2), and three equivalent Ti(1) atoms.