The material structure described by TlBiSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. Tl(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form TlSe6 octahedra that share corners with six equivalent Tl(1)Se6 octahedra, edges with four equivalent Tl(1)Se6 octahedra, and edges with eight equivalent Bi(1)Se6 octahedra. The corner-sharing octahedra are not tilted. Bi(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form BiSe6 octahedra that share corners with six equivalent Bi(1)Se6 octahedra, edges with four equivalent Bi(1)Se6 octahedra, and edges with eight equivalent Tl(1)Se6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Tl(1) and four equivalent Bi(1) atoms to form SeTl2Bi4 octahedra that share corners with six equivalent Se(1)Tl2Bi4 octahedra, edges with four equivalent Se(1)Tl2Bi4 octahedra, and edges with eight equivalent Se(2)Tl4Bi2 octahedra. The corner-sharing octahedra are not tilted. In the second Se site, Se(2) is bonded to four equivalent Tl(1) and two equivalent Bi(1) atoms to form SeTl4Bi2 octahedra that share corners with six equivalent Se(2)Tl4Bi2 octahedra, edges with four equivalent Se(2)Tl4Bi2 octahedra, and edges with eight equivalent Se(1)Tl2Bi4 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_TlBiSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.350
_cell_length_b   4.350
_cell_length_c   6.126
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   115.904
_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  Tl0  1  0.000  0.000  0.000  1.0
  Bi  Bi1  1  0.500  0.500  0.500  1.0
  Se  Se2  1  0.000  0.000  0.500  1.0
  Se  Se3  1  0.500  0.500  0.000  1.0
[/CIF]
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The material structure described by TlBiSe2 is Caswellsilverite-like structured and crystallizes in the tetragonal P4/mmm space group. Tl(1) is bonded to two equivalent Se(1) and four equivalent Se(2) atoms to form TlSe6 octahedra that share corners with six equivalent Tl(1)Se6 octahedra, edges with four equivalent Tl(1)Se6 octahedra, and edges with eight equivalent Bi(1)Se6 octahedra. The corner-sharing octahedra are not tilted. Bi(1) is bonded to two equivalent Se(2) and four equivalent Se(1) atoms to form BiSe6 octahedra that share corners with six equivalent Bi(1)Se6 octahedra, edges with four equivalent Bi(1)Se6 octahedra, and edges with eight equivalent Tl(1)Se6 octahedra. The corner-sharing octahedra are not tilted. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to two equivalent Tl(1) and four equivalent Bi(1) atoms to form SeTl2Bi4 octahedra that share corners with six equivalent Se(1)Tl2Bi4 octahedra, edges with four equivalent Se(1)Tl2Bi4 octahedra, and edges with eight equivalent Se(2)Tl4Bi2 octahedra. The corner-sharing octahedra are not tilted. In the second Se site, Se(2) is bonded to four equivalent Tl(1) and two equivalent Bi(1) atoms to form SeTl4Bi2 octahedra that share corners with six equivalent Se(2)Tl4Bi2 octahedra, edges with four equivalent Se(2)Tl4Bi2 octahedra, and edges with eight equivalent Se(1)Tl2Bi4 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF file [CIF]
data_TlBiSe2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.350
_cell_length_b   4.350
_cell_length_c   6.126
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   115.904
_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  Tl0  1  0.000  0.000  0.000  1.0
  Bi  Bi1  1  0.500  0.500  0.500  1.0
  Se  Se2  1  0.000  0.000  0.500  1.0
  Se  Se3  1  0.500  0.500  0.000  1.0
[/CIF]
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