data_Tl2InSe
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.94
_cell_length_b   8.94
_cell_length_c   8.94
_cell_angle_alpha   26.39
_cell_angle_beta   26.39
_cell_angle_gamma   26.39
_symmetry_Int_Tables_number   1
_chemical_formula_structural   Tl2InSe
_chemical_formula_sum   'Tl2 In1 Se1'
_cell_volume   124.45
_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  Tl2  1  0.0  0.0  0.1  1.0
  Tl  Tl3  1  0.0  0.0  0.77  1.0
  In  In0  1  0.0  0.0  0.94  1.0
  Se  Se1  1  0.0  0.0  0.0  1.0

data_Tl2InSe
_symmetry_space_group_name_H-M   Cm
_cell_length_a   7.07
_cell_length_b   4.08
_cell_length_c   8.94
_cell_angle_alpha   90.0
_cell_angle_beta   105.28
_cell_angle_gamma   90.0
_symmetry_Int_Tables_number   8
_chemical_formula_structural   Tl2InSe
_chemical_formula_sum   'Tl4 In2 Se2'
_cell_volume   248.89
_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  0.23  1.0
  Tl  Tl1  2  0.0  0.0  0.9  1.0
  In  In2  2  0.0  0.0  0.06  1.0
  Se  Se3  2  0.0  0.0  0.0  1.0

Tl Tl In Se
Tl2InSe is Cyanogen Chloride-like structured and crystallizes in the monoclinic Cm space group. The structure is zero-dimensional and consists of two Tl2InSe clusters. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a single-bond geometry to one Se(1) atom. The Tl(1)-Se(1) bond length is 0.91 Å. In the second Tl site, Tl(2) is bonded in a single-bond geometry to one In(1) atom. The Tl(2)-In(1) bond length is 1.47 Å. In(1) is bonded in a distorted linear geometry to one Tl(2) and one Se(1) atom. The In(1)-Se(1) bond length is 0.56 Å. Se(1) is bonded in a linear geometry to one Tl(1) and one In(1) atom.