The crystal structure described by Tl2SeO4 crystallizes in the monoclinic Cc space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the second Tl site, Tl(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form TlO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra and edges with two equivalent Tl(2)O6 octahedra. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share corners with six equivalent Tl(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-52°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Tl(1), two equivalent Tl(2), and one Se(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Tl(1), one Tl(2), and one Se(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Tl(1), one Tl(2), and one Se(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Tl(1), two equivalent Tl(2), and one Se(1) atom. is represented by the CIF file [CIF]
data_Tl2SeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.099
_cell_length_b   6.099
_cell_length_c   8.267
_cell_angle_alpha   90.013
_cell_angle_beta   90.013
_cell_angle_gamma   116.049
_symmetry_Int_Tables_number   1
_cell_volume   276.309
_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  0.306  0.686  0.257  1.0
  Tl  Tl1  1  0.999  0.998  0.005  1.0
  Tl  Tl2  1  0.686  0.306  0.757  1.0
  Tl  Tl3  1  0.998  0.999  0.505  1.0
  Se  Se4  1  0.358  0.643  0.757  1.0
  Se  Se5  1  0.643  0.358  0.257  1.0
  O  O6  1  0.661  0.749  0.754  1.0
  O  O7  1  0.273  0.737  0.923  1.0
  O  O8  1  0.266  0.741  0.596  1.0
  O  O9  1  0.243  0.339  0.756  1.0
  O  O10  1  0.741  0.266  0.096  1.0
  O  O11  1  0.749  0.661  0.254  1.0
  O  O12  1  0.737  0.273  0.423  1.0
  O  O13  1  0.339  0.243  0.256  1.0
[/CIF]
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The crystal structure described by Tl2SeO4 crystallizes in the monoclinic Cc space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a 4-coordinate geometry to one O(1), one O(2), one O(3), and one O(4) atom. In the second Tl site, Tl(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form TlO6 octahedra that share corners with six equivalent Se(1)O4 tetrahedra and edges with two equivalent Tl(2)O6 octahedra. Se(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form SeO4 tetrahedra that share corners with six equivalent Tl(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-52°. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Tl(1), two equivalent Tl(2), and one Se(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to one Tl(1), one Tl(2), and one Se(1) atom. In the third O site, O(3) is bonded in a single-bond geometry to one Tl(1), one Tl(2), and one Se(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Tl(1), two equivalent Tl(2), and one Se(1) atom. is represented by the CIF file [CIF]
data_Tl2SeO4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.099
_cell_length_b   6.099
_cell_length_c   8.267
_cell_angle_alpha   90.013
_cell_angle_beta   90.013
_cell_angle_gamma   116.049
_symmetry_Int_Tables_number   1
_cell_volume   276.309
_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  0.306  0.686  0.257  1.0
  Tl  Tl1  1  0.999  0.998  0.005  1.0
  Tl  Tl2  1  0.686  0.306  0.757  1.0
  Tl  Tl3  1  0.998  0.999  0.505  1.0
  Se  Se4  1  0.358  0.643  0.757  1.0
  Se  Se5  1  0.643  0.358  0.257  1.0
  O  O6  1  0.661  0.749  0.754  1.0
  O  O7  1  0.273  0.737  0.923  1.0
  O  O8  1  0.266  0.741  0.596  1.0
  O  O9  1  0.243  0.339  0.756  1.0
  O  O10  1  0.741  0.266  0.096  1.0
  O  O11  1  0.749  0.661  0.254  1.0
  O  O12  1  0.737  0.273  0.423  1.0
  O  O13  1  0.339  0.243  0.256  1.0
[/CIF]
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