The crystal structure described by Tl6Si2O7 crystallizes in the trigonal P3 space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a distorted single-bond geometry to one O(2) atom. In the second Tl site, Tl(2) is bonded in a 3-coordinate geometry to 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(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 distorted tetrahedral geometry to three equivalent Tl(2) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tl6Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.444
_cell_length_b   9.444
_cell_length_c   4.881
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   376.993
_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  0.292  0.317  0.743  1.0
  Tl  Tl1  1  0.683  0.975  0.743  1.0
  Tl  Tl2  1  0.025  0.708  0.743  1.0
  Tl  Tl3  1  0.425  0.060  0.206  1.0
  Tl  Tl4  1  0.940  0.365  0.206  1.0
  Tl  Tl5  1  0.635  0.575  0.206  1.0
  Si  Si6  1  0.000  0.000  0.233  1.0
  Si  Si7  1  0.667  0.333  0.670  1.0
  O  O8  1  0.864  0.053  0.232  1.0
  O  O9  1  0.947  0.811  0.232  1.0
  O  O10  1  0.189  0.136  0.232  1.0
  O  O11  1  0.786  0.261  0.770  1.0
  O  O12  1  0.739  0.525  0.770  1.0
  O  O13  1  0.475  0.214  0.770  1.0
  O  O14  1  0.667  0.333  0.330  1.0
[/CIF]
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The crystal structure described by Tl6Si2O7 crystallizes in the trigonal P3 space group. There are two inequivalent Tl sites. In the first Tl site, Tl(1) is bonded in a distorted single-bond geometry to one O(2) atom. In the second Tl site, Tl(2) is bonded in a 3-coordinate geometry to 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(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 distorted tetrahedral geometry to three equivalent Tl(2) and one Si(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Tl6Si2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.444
_cell_length_b   9.444
_cell_length_c   4.881
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   376.993
_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  0.292  0.317  0.743  1.0
  Tl  Tl1  1  0.683  0.975  0.743  1.0
  Tl  Tl2  1  0.025  0.708  0.743  1.0
  Tl  Tl3  1  0.425  0.060  0.206  1.0
  Tl  Tl4  1  0.940  0.365  0.206  1.0
  Tl  Tl5  1  0.635  0.575  0.206  1.0
  Si  Si6  1  0.000  0.000  0.233  1.0
  Si  Si7  1  0.667  0.333  0.670  1.0
  O  O8  1  0.864  0.053  0.232  1.0
  O  O9  1  0.947  0.811  0.232  1.0
  O  O10  1  0.189  0.136  0.232  1.0
  O  O11  1  0.786  0.261  0.770  1.0
  O  O12  1  0.739  0.525  0.770  1.0
  O  O13  1  0.475  0.214  0.770  1.0
  O  O14  1  0.667  0.333  0.330  1.0
[/CIF]
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