The compound described by Tl5Se2I crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 3-coordinate geometry to three equivalent Se(1) atoms. In the second Tl site, Tl(2) is bonded to four equivalent Se(1) and two equivalent I(1) atoms to form corner-sharing TlSe4I2 octahedra. The corner-sharing octahedral tilt angles range from 0-39°. Se(1) is bonded in a 8-coordinate geometry to two equivalent Tl(2) and six equivalent Tl(1) atoms. I(1) is bonded in a linear geometry to two equivalent Tl(2) atoms. is represented by the CIF file [CIF]
data_Tl5Se2I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.778
_cell_length_b   8.778
_cell_length_c   9.289
_cell_angle_alpha   118.194
_cell_angle_beta   118.194
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   532.490
_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  Tl0  1  0.993  0.781  0.274  1.0
  Tl  Tl1  1  0.781  0.281  0.274  1.0
  Tl  Tl2  1  0.493  0.993  0.274  1.0
  Tl  Tl3  1  0.219  0.719  0.726  1.0
  Tl  Tl4  1  0.281  0.493  0.274  1.0
  Tl  Tl5  1  0.007  0.219  0.726  1.0
  Tl  Tl6  1  0.719  0.507  0.726  1.0
  Tl  Tl7  1  0.507  0.007  0.726  1.0
  Tl  Tl8  1  0.500  0.500  0.000  1.0
  Tl  Tl9  1  0.000  0.000  0.000  1.0
  Se  Se10  1  0.837  0.337  0.000  1.0
  Se  Se11  1  0.663  0.837  0.000  1.0
  Se  Se12  1  0.337  0.163  0.000  1.0
  Se  Se13  1  0.163  0.663  0.000  1.0
  I  I14  1  0.750  0.750  0.500  1.0
  I  I15  1  0.250  0.250  0.500  1.0
[/CIF]
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The compound described by Tl5Se2I crystallizes in the tetragonal I4/mcm space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 3-coordinate geometry to three equivalent Se(1) atoms. In the second Tl site, Tl(2) is bonded to four equivalent Se(1) and two equivalent I(1) atoms to form corner-sharing TlSe4I2 octahedra. The corner-sharing octahedral tilt angles range from 0-39°. Se(1) is bonded in a 8-coordinate geometry to two equivalent Tl(2) and six equivalent Tl(1) atoms. I(1) is bonded in a linear geometry to two equivalent Tl(2) atoms. is represented by the CIF file [CIF]
data_Tl5Se2I
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.778
_cell_length_b   8.778
_cell_length_c   9.289
_cell_angle_alpha   118.194
_cell_angle_beta   118.194
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   532.490
_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  Tl0  1  0.993  0.781  0.274  1.0
  Tl  Tl1  1  0.781  0.281  0.274  1.0
  Tl  Tl2  1  0.493  0.993  0.274  1.0
  Tl  Tl3  1  0.219  0.719  0.726  1.0
  Tl  Tl4  1  0.281  0.493  0.274  1.0
  Tl  Tl5  1  0.007  0.219  0.726  1.0
  Tl  Tl6  1  0.719  0.507  0.726  1.0
  Tl  Tl7  1  0.507  0.007  0.726  1.0
  Tl  Tl8  1  0.500  0.500  0.000  1.0
  Tl  Tl9  1  0.000  0.000  0.000  1.0
  Se  Se10  1  0.837  0.337  0.000  1.0
  Se  Se11  1  0.663  0.837  0.000  1.0
  Se  Se12  1  0.337  0.163  0.000  1.0
  Se  Se13  1  0.163  0.663  0.000  1.0
  I  I14  1  0.750  0.750  0.500  1.0
  I  I15  1  0.250  0.250  0.500  1.0
[/CIF]
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