The compound described by Tl2HgSiSe4 crystallizes in the tetragonal I-42m space group. Hg(1) is bonded in a 4-coordinate geometry to four equivalent Se(1) atoms. Tl(1) is bonded in a 6-coordinate geometry to two equivalent Tl(1) and four equivalent Se(1) atoms. Si(1) is bonded in a tetrahedral geometry to four equivalent Se(1) atoms. Se(1) is bonded in a distorted L-shaped geometry to one Hg(1), two equivalent Tl(1), and one Si(1) atom. is represented by the CIF file [CIF]
data_Tl2SiHgSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.733
_cell_length_b   6.733
_cell_length_c   6.733
_cell_angle_alpha   105.081
_cell_angle_beta   105.081
_cell_angle_gamma   118.662
_symmetry_Int_Tables_number   1
_cell_volume   230.370
_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  0.500  0.000  0.500  1.0
  Tl  Tl1  1  0.000  0.500  0.500  1.0
  Si  Si2  1  0.000  0.000  0.000  1.0
  Hg  Hg3  1  0.500  0.500  0.000  1.0
  Se  Se4  1  0.955  0.636  0.000  1.0
  Se  Se5  1  0.636  0.955  0.000  1.0
  Se  Se6  1  0.045  0.045  0.681  1.0
  Se  Se7  1  0.364  0.364  0.319  1.0
[/CIF]
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The compound described by Tl2HgSiSe4 crystallizes in the tetragonal I-42m space group. Hg(1) is bonded in a 4-coordinate geometry to four equivalent Se(1) atoms. Tl(1) is bonded in a 6-coordinate geometry to two equivalent Tl(1) and four equivalent Se(1) atoms. Si(1) is bonded in a tetrahedral geometry to four equivalent Se(1) atoms. Se(1) is bonded in a distorted L-shaped geometry to one Hg(1), two equivalent Tl(1), and one Si(1) atom. is represented by the CIF file [CIF]
data_Tl2SiHgSe4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.733
_cell_length_b   6.733
_cell_length_c   6.733
_cell_angle_alpha   105.081
_cell_angle_beta   105.081
_cell_angle_gamma   118.662
_symmetry_Int_Tables_number   1
_cell_volume   230.370
_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  0.500  0.000  0.500  1.0
  Tl  Tl1  1  0.000  0.500  0.500  1.0
  Si  Si2  1  0.000  0.000  0.000  1.0
  Hg  Hg3  1  0.500  0.500  0.000  1.0
  Se  Se4  1  0.955  0.636  0.000  1.0
  Se  Se5  1  0.636  0.955  0.000  1.0
  Se  Se6  1  0.045  0.045  0.681  1.0
  Se  Se7  1  0.364  0.364  0.319  1.0
[/CIF]
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