data_NbTl2Cu
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.12
_cell_length_b   6.12
_cell_length_c   6.12
_cell_angle_alpha   150.6
_cell_angle_beta   131.86
_cell_angle_gamma   57.42
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbTl2Cu
_chemical_formula_sum   'Nb1 Tl2 Cu1'
_cell_volume   83.07
_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
  Nb  Nb1  1  0.0  0.49  0.41  1.0
  Tl  Tl2  1  0.0  0.0  0.58  1.0
  Tl  Tl3  1  0.55  0.0  0.85  1.0
  Cu  Cu0  1  0.0  0.0  0.61  1.0

data_NbTl2Cu
_symmetry_space_group_name_H-M   P1
_cell_length_a   3.1
_cell_length_b   4.99
_cell_length_c   6.12
_cell_angle_alpha   114.07
_cell_angle_beta   104.7
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   NbTl2Cu
_chemical_formula_sum   'Nb1 Tl2 Cu1'
_cell_volume   83.07
_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
  Nb  Nb0  1  0.51  0.92  0.92  1.0
  Tl  Tl1  1  0.0  0.58  0.58  1.0
  Tl  Tl2  1  0.0  0.85  0.3  1.0
  Cu  Cu3  1  0.0  0.61  0.61  1.0

Nb Tl Tl Cu
Nb Tl Tl Cu 0 2 - o - 0 3 o + o 0 1 o + o 1 3 o o o 1 2 o o o 2 2 o + + 2 3 o o o 
NbCuTl2 crystallizes in the triclinic P1 space group. Nb(1) is bonded in a 1-coordinate geometry to one Cu(1) and two equivalent Tl(2) atoms. The Nb(1)-Cu(1) bond length is 2.12 Å. There is one shorter (2.59 Å) and one longer (3.24 Å) Nb(1)-Tl(2) bond length. Cu(1) is bonded in a single-bond geometry to one Nb(1), one Tl(1), and one Tl(2) atom. The Cu(1)-Tl(1) bond length is 0.23 Å. The Cu(1)-Tl(2) bond length is 2.64 Å. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a single-bond geometry to one Cu(1) and two equivalent Tl(2) atoms. There is one shorter (2.58 Å) and one longer (3.31 Å) Tl(1)-Tl(2) bond length. In the second Tl site, Tl(2) is bonded in a 7-coordinate geometry to two equivalent Nb(1), one Cu(1), two equivalent Tl(1), and two equivalent Tl(2) atoms. Both Tl(2)-Tl(2) bond lengths are 3.10 Å.