The crystal structure described by La5TlSe8 crystallizes in the tetragonal I-4 space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second La site, La(2) is bonded in a distorted hexagonal bipyramidal geometry to four equivalent Se(1) and four equivalent Se(2) atoms. Tl(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one La(2), four equivalent La(1), and one Tl(1) atom. In the second Se site, Se(2) is bonded to one La(2), four equivalent La(1), and one Tl(1) atom to form a mixture of distorted edge, corner, and face-sharing SeLa5Tl octahedra. The corner-sharing octahedral tilt angles range from 17-47°. is represented by the CIF file [CIF]
data_La5TlSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.943
_cell_length_b   7.943
_cell_length_c   7.943
_cell_angle_alpha   109.132
_cell_angle_beta   110.151
_cell_angle_gamma   109.132
_symmetry_Int_Tables_number   1
_cell_volume   385.691
_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
  La  La0  1  0.243  0.630  0.378  1.0
  La  La1  1  0.375  0.250  0.625  1.0
  La  La2  1  0.748  0.870  0.112  1.0
  La  La3  1  0.622  0.365  0.252  1.0
  La  La4  1  0.888  0.135  0.757  1.0
  Tl  Tl5  1  0.125  0.750  0.875  1.0
  Se  Se6  1  0.995  0.858  0.489  1.0
  Se  Se7  1  0.996  0.337  0.488  1.0
  Se  Se8  1  0.512  0.008  0.849  1.0
  Se  Se9  1  0.151  0.163  0.159  1.0
  Se  Se10  1  0.363  0.493  0.005  1.0
  Se  Se11  1  0.631  0.642  0.637  1.0
  Se  Se12  1  0.511  0.007  0.369  1.0
  Se  Se13  1  0.841  0.492  0.004  1.0
[/CIF]
.
The crystal structure described by La5TlSe8 crystallizes in the tetragonal I-4 space group. There are two inequivalent La sites. In the first La site, La(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. In the second La site, La(2) is bonded in a distorted hexagonal bipyramidal geometry to four equivalent Se(1) and four equivalent Se(2) atoms. Tl(1) is bonded in a 8-coordinate geometry to four equivalent Se(1) and four equivalent Se(2) atoms. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one La(2), four equivalent La(1), and one Tl(1) atom. In the second Se site, Se(2) is bonded to one La(2), four equivalent La(1), and one Tl(1) atom to form a mixture of distorted edge, corner, and face-sharing SeLa5Tl octahedra. The corner-sharing octahedral tilt angles range from 17-47°. is represented by the CIF file [CIF]
data_La5TlSe8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.943
_cell_length_b   7.943
_cell_length_c   7.943
_cell_angle_alpha   109.132
_cell_angle_beta   110.151
_cell_angle_gamma   109.132
_symmetry_Int_Tables_number   1
_cell_volume   385.691
_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
  La  La0  1  0.243  0.630  0.378  1.0
  La  La1  1  0.375  0.250  0.625  1.0
  La  La2  1  0.748  0.870  0.112  1.0
  La  La3  1  0.622  0.365  0.252  1.0
  La  La4  1  0.888  0.135  0.757  1.0
  Tl  Tl5  1  0.125  0.750  0.875  1.0
  Se  Se6  1  0.995  0.858  0.489  1.0
  Se  Se7  1  0.996  0.337  0.488  1.0
  Se  Se8  1  0.512  0.008  0.849  1.0
  Se  Se9  1  0.151  0.163  0.159  1.0
  Se  Se10  1  0.363  0.493  0.005  1.0
  Se  Se11  1  0.631  0.642  0.637  1.0
  Se  Se12  1  0.511  0.007  0.369  1.0
  Se  Se13  1  0.841  0.492  0.004  1.0
[/CIF]
.