data_TlAu2Se
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.14
_cell_length_b   5.14
_cell_length_c   5.14
_cell_angle_alpha   125.82
_cell_angle_beta   125.82
_cell_angle_gamma   80.18
_symmetry_Int_Tables_number   1
_chemical_formula_structural   TlAu2Se
_chemical_formula_sum   'Tl1 Au2 Se1'
_cell_volume   86.23
_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
  Tl  Tl3  1  0.0  0.0  0.93  1.0
  Au  Au0  1  0.0  0.34  0.97  1.0
  Au  Au1  1  0.34  0.0  0.97  1.0
  Se  Se2  1  0.0  0.0  0.0  1.0

data_TlAu2Se
_symmetry_space_group_name_H-M   Cm
_cell_length_a   6.62
_cell_length_b   6.62
_cell_length_c   5.14
_cell_angle_alpha   90.0
_cell_angle_beta   130.09
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   TlAu2Se
_chemical_formula_sum   'Tl2 Au4 Se2'
_cell_volume   172.47
_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
  Tl  Tl0  2  0.0  0.0  0.93  1.0
  Au  Au1  4  0.33  0.33  0.63  1.0
  Se  Se2  2  0.0  0.0  0.0  1.0

Tl Au Au Se
Au2TlSe is Copper structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Au2TlSe clusters. Au(1) is bonded in a single-bond geometry to one Tl(1) atom. The Au(1)-Tl(1) bond length is 1.66 Å. Tl(1) is bonded in a distorted single-bond geometry to two equivalent Au(1) and one Se(1) atom. The Tl(1)-Se(1) bond length is 0.34 Å. Se(1) is bonded in a single-bond geometry to one Tl(1) atom.