The compound described by LiTl6Si2O7 crystallizes in the trigonal P3 space group. Li(1) is bonded in a trigonal non-coplanar geometry to three equivalent Tl(2) atoms. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a distorted L-shaped geometry to one O(1) and one O(2) atom. In the second Tl site, Tl(2) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one O(1), one O(2), and one O(3) atom. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a trigonal planar geometry to three equivalent O(1) atoms. In the second Si site, Si(2) is bonded in a tetrahedral geometry to one O(3) and three equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Tl(1), one Tl(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Tl(1), one Tl(2), and one Si(2) atom. In the third O site, O(3) is bonded in a tetrahedral geometry to three equivalent Tl(2) and one Si(2) atom. is represented by the CIF file [CIF]
data_LiTl6Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.203
_cell_length_b   8.516
_cell_length_c   8.514
_cell_angle_alpha   59.987
_cell_angle_beta   90.006
_cell_angle_gamma   90.003
_symmetry_Int_Tables_number   1
_cell_volume   326.662
_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
  Li  Li0  1  0.362  1.000  0.000  1.0
  Tl  Tl1  1  0.727  0.711  0.382  1.0
  Tl  Tl2  1  0.727  0.907  0.711  1.0
  Tl  Tl3  1  0.727  0.382  0.907  1.0
  Tl  Tl4  1  0.194  0.271  0.632  1.0
  Tl  Tl5  1  0.194  0.098  0.271  1.0
  Tl  Tl6  1  0.194  0.632  0.098  1.0
  Si  Si7  1  0.213  0.667  0.667  1.0
  Si  Si8  1  0.688  0.333  0.333  1.0
  O  O9  1  0.247  0.877  0.605  1.0
  O  O10  1  0.247  0.518  0.877  1.0
  O  O11  1  0.247  0.605  0.518  1.0
  O  O12  1  0.789  0.128  0.391  1.0
  O  O13  1  0.789  0.481  0.127  1.0
  O  O14  1  0.789  0.392  0.481  1.0
  O  O15  1  0.365  0.333  0.333  1.0
[/CIF]
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The compound described by LiTl6Si2O7 crystallizes in the trigonal P3 space group. Li(1) is bonded in a trigonal non-coplanar geometry to three equivalent Tl(2) atoms. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a distorted L-shaped geometry to one O(1) and one O(2) atom. In the second Tl site, Tl(2) is bonded in a distorted rectangular see-saw-like geometry to one Li(1), one O(1), one O(2), and one O(3) atom. There are two inequivalent Si sites. In the first Si site, Si(1) is bonded in a trigonal planar geometry to three equivalent O(1) atoms. In the second Si site, Si(2) is bonded in a tetrahedral geometry to one O(3) and three equivalent O(2) atoms. There are three inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to one Tl(1), one Tl(2), and one Si(1) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to one Tl(1), one Tl(2), and one Si(2) atom. In the third O site, O(3) is bonded in a tetrahedral geometry to three equivalent Tl(2) and one Si(2) atom. is represented by the CIF file [CIF]
data_LiTl6Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.203
_cell_length_b   8.516
_cell_length_c   8.514
_cell_angle_alpha   59.987
_cell_angle_beta   90.006
_cell_angle_gamma   90.003
_symmetry_Int_Tables_number   1
_cell_volume   326.662
_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
  Li  Li0  1  0.362  1.000  0.000  1.0
  Tl  Tl1  1  0.727  0.711  0.382  1.0
  Tl  Tl2  1  0.727  0.907  0.711  1.0
  Tl  Tl3  1  0.727  0.382  0.907  1.0
  Tl  Tl4  1  0.194  0.271  0.632  1.0
  Tl  Tl5  1  0.194  0.098  0.271  1.0
  Tl  Tl6  1  0.194  0.632  0.098  1.0
  Si  Si7  1  0.213  0.667  0.667  1.0
  Si  Si8  1  0.688  0.333  0.333  1.0
  O  O9  1  0.247  0.877  0.605  1.0
  O  O10  1  0.247  0.518  0.877  1.0
  O  O11  1  0.247  0.605  0.518  1.0
  O  O12  1  0.789  0.128  0.391  1.0
  O  O13  1  0.789  0.481  0.127  1.0
  O  O14  1  0.789  0.392  0.481  1.0
  O  O15  1  0.365  0.333  0.333  1.0
[/CIF]
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