data_HfNbTl2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.11
_cell_length_b   3.11
_cell_length_c   8.87
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   HfNbTl2
_chemical_formula_sum   'Hf1 Nb1 Tl2'
_cell_volume   85.55
_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
  Hf  Hf0  1  0.0  0.0  0.44  1.0
  Nb  Nb1  1  0.0  0.0  0.0  1.0
  Tl  Tl2  1  0.55  0.55  0.16  1.0
  Tl  Tl3  1  0.55  0.55  0.71  1.0

data_HfNbTl2
_symmetry_space_group_name_H-M   Cm
_cell_length_a   4.39
_cell_length_b   4.39
_cell_length_c   8.87
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   HfNbTl2
_chemical_formula_sum   'Hf2 Nb2 Tl4'
_cell_volume   171.09
_cell_formula_units_Z   2
loop_
 _symmetry_equiv_pos_site_id
 _symmetry_equiv_pos_as_xyz
  1  'x, y, z'
  2  'x, -y, z'
  3  'x+1/2, y+1/2, z'
  4  'x+1/2, -y+1/2, 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
  Hf  Hf0  2  0.0  0.0  0.44  1.0
  Nb  Nb1  2  0.0  0.0  0.0  1.0
  Tl  Tl2  2  0.05  0.5  0.16  1.0
  Tl  Tl3  2  0.05  0.5  0.71  1.0

Hf Nb Tl Tl
HfNbTl2 crystallizes in the monoclinic Cm space group. Hf(1) is bonded to four equivalent Hf(1), four equivalent Tl(1), and four equivalent Tl(2) atoms to form distorted HfHf4Tl8 cuboctahedra that share corners with four equivalent Hf(1)Hf4Tl8 cuboctahedra, edges with eight equivalent Tl(2)Hf4Nb4Tl4 cuboctahedra, faces with four equivalent Tl(2)Hf4Nb4Tl4 cuboctahedra, and faces with eight equivalent Hf(1)Hf4Tl8 cuboctahedra. All Hf(1)-Hf(1) bond lengths are 3.11 Å. There are a spread of Hf(1)-Tl(1) bond distances ranging from 3.11-3.42 Å. There are a spread of Hf(1)-Tl(2) bond distances ranging from 3.11-3.42 Å. Nb(1) is bonded in a 12-coordinate geometry to four equivalent Nb(1), four equivalent Tl(1), and four equivalent Tl(2) atoms. All Nb(1)-Nb(1) bond lengths are 3.11 Å. There are a spread of Nb(1)-Tl(1) bond distances ranging from 2.44-2.83 Å. There are a spread of Nb(1)-Tl(2) bond distances ranging from 3.26-3.56 Å. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 12-coordinate geometry to four equivalent Hf(1), four equivalent Nb(1), and four equivalent Tl(1) atoms. All Tl(1)-Tl(1) bond lengths are 3.11 Å. In the second Tl site, Tl(2) is bonded to four equivalent Hf(1), four equivalent Nb(1), and four equivalent Tl(2) atoms to form distorted TlHf4Nb4Tl4 cuboctahedra that share corners with four equivalent Tl(2)Hf4Nb4Tl4 cuboctahedra, edges with eight equivalent Hf(1)Hf4Tl8 cuboctahedra, faces with four equivalent Hf(1)Hf4Tl8 cuboctahedra, and faces with eight equivalent Tl(2)Hf4Nb4Tl4 cuboctahedra. All Tl(2)-Tl(2) bond lengths are 3.11 Å.