data_TlB3
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.7
_cell_length_b   4.7
_cell_length_c   4.7
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TlB3
_chemical_formula_sum   'Tl2 B6'
_cell_volume   103.97
_cell_formula_units_Z   2
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
  Tl  Tl6  1  0.35  0.35  0.35  1.0
  Tl  Tl7  1  0.0  0.0  0.0  1.0
  B  B0  1  0.18  0.0  0.35  1.0
  B  B1  1  0.53  0.0  0.35  1.0
  B  B2  1  0.35  0.18  0.0  1.0
  B  B3  1  0.35  0.53  0.0  1.0
  B  B4  1  0.0  0.35  0.53  1.0
  B  B5  1  0.0  0.35  0.18  1.0

data_TlB3
_symmetry_space_group_name_H-M   R3
_cell_length_a   6.65
_cell_length_b   6.65
_cell_length_c   8.14
_cell_angle_alpha   90.0
_cell_angle_beta   90.0
_cell_angle_gamma   120.0
_symmetry_Int_Tables_number   146
_chemical_formula_structural   TlB3
_chemical_formula_sum   'Tl6 B18'
_cell_volume   311.9
_cell_formula_units_Z   6
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  'x+1/3, y+2/3, z+2/3'
  5  '-y+1/3, x-y+2/3, z+2/3'
  6  '-x+y+1/3, -x+2/3, z+2/3'
  7  'x+2/3, y+1/3, z+1/3'
  8  '-y+2/3, x-y+1/3, z+1/3'
  9  '-x+y+2/3, -x+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
  Tl  Tl0  3  0.0  0.0  0.0  1.0
  Tl  Tl1  3  0.0  0.0  0.35  1.0
  B  B2  9  0.0  0.82  0.18  1.0
  B  B3  9  0.04  0.43  0.96  1.0

Tl Tl B B B B B B
TlB3 crystallizes in the trigonal R3 space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 6-coordinate geometry to three equivalent B(1) and three equivalent B(2) atoms. All Tl(1)-B(1) bond lengths are 1.85 Å. All Tl(1)-B(2) bond lengths are 1.85 Å. In the second Tl site, Tl(2) is bonded in a 3-coordinate geometry to three equivalent B(1) and three equivalent B(2) atoms. All Tl(2)-B(1) bond lengths are 1.85 Å. All Tl(2)-B(2) bond lengths are 2.77 Å. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 6-coordinate geometry to one Tl(1), one Tl(2), two equivalent B(1), and two equivalent B(2) atoms. Both B(1)-B(1) bond lengths are 2.02 Å. There is one shorter (1.65 Å) and one longer (2.02 Å) B(1)-B(2) bond length. In the second B site, B(2) is bonded in a 4-coordinate geometry to one Tl(1), one Tl(2), and two equivalent B(1) atoms.