data_La2TlNi
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.17
_cell_length_b   5.17
_cell_length_c   5.17
_cell_angle_alpha   60.0
_cell_angle_beta   60.0
_cell_angle_gamma   60.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   La2TlNi
_chemical_formula_sum   'La2 Tl1 Ni1'
_cell_volume   97.58
_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
  La  La0  1  0.65  0.65  0.65  1.0
  La  La1  1  0.48  0.48  0.48  1.0
  Tl  Tl3  1  0.83  0.83  0.83  1.0
  Ni  Ni2  1  0.0  0.0  0.0  1.0

data_La2TlNi
_symmetry_space_group_name_H-M   R3m
_cell_length_a   5.17
_cell_length_b   5.17
_cell_length_c   12.66
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   160
_chemical_formula_structural   La2TlNi
_chemical_formula_sum   'La6 Tl3 Ni3'
_cell_volume   292.73
_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
  La  La0  3  0.0  0.0  0.35  1.0
  La  La1  3  0.0  0.0  0.52  1.0
  Tl  Tl2  3  0.0  0.0  0.17  1.0
  Ni  Ni3  3  0.0  0.0  0.0  1.0

La La Tl Ni
La La Tl Ni 0 1 o o o 0 2 o o o 2 3 + + + 
La2NiTl crystallizes in the trigonal R3m space group. There are two inequivalent La sites. In the first La site, La(1) is bonded to one La(2), three equivalent Ni(1), and one Tl(1) atom to form distorted LaLaTlNi3 trigonal bipyramids that share corners with six equivalent La(1)LaTlNi3 trigonal bipyramids and edges with three equivalent Tl(1)La4Ni trigonal bipyramids. The La(1)-La(2) bond length is 2.19 Å. All La(1)-Ni(1) bond lengths are 2.99 Å. The La(1)-Tl(1) bond length is 2.19 Å. In the second La site, La(2) is bonded in a 7-coordinate geometry to one La(1), three equivalent Ni(1), and three equivalent Tl(1) atoms. All La(2)-Ni(1) bond lengths are 3.52 Å. All La(2)-Tl(1) bond lengths are 2.99 Å. Ni(1) is bonded in a 7-coordinate geometry to three equivalent La(1), three equivalent La(2), and one Tl(1) atom. The Ni(1)-Tl(1) bond length is 2.19 Å. Tl(1) is bonded to one La(1), three equivalent La(2), and one Ni(1) atom to form distorted TlLa4Ni trigonal bipyramids that share corners with six equivalent Tl(1)La4Ni trigonal bipyramids and edges with three equivalent La(1)LaTlNi3 trigonal bipyramids.