The structure described by Hg6Si2O7 crystallizes in the monoclinic C2/m space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a 3-coordinate geometry to one O(3) and two equivalent O(2) atoms. In the second Hg site, Hg(2) is bonded in a single-bond geometry to one O(3) atom. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Hg(1) and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Hg(2), two equivalent Hg(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Si2Hg6O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.104
_cell_length_b   7.054
_cell_length_c   7.054
_cell_angle_alpha   65.348
_cell_angle_beta   71.965
_cell_angle_gamma   71.965
_symmetry_Int_Tables_number   1
_cell_volume   256.728
_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
  Si  Si0  1  0.102  0.353  0.353  1.0
  Si  Si1  1  0.898  0.647  0.647  1.0
  Hg  Hg2  1  0.418  0.876  0.356  1.0
  Hg  Hg3  1  0.582  0.644  0.124  1.0
  Hg  Hg4  1  0.582  0.124  0.644  1.0
  Hg  Hg5  1  0.418  0.356  0.876  1.0
  Hg  Hg6  1  0.047  0.885  0.885  1.0
  Hg  Hg7  1  0.953  0.115  0.115  1.0
  O  O8  1  0.000  0.500  0.500  1.0
  O  O9  1  0.261  0.130  0.484  1.0
  O  O10  1  0.739  0.516  0.870  1.0
  O  O11  1  0.739  0.870  0.516  1.0
  O  O12  1  0.261  0.484  0.130  1.0
  O  O13  1  0.120  0.693  0.693  1.0
  O  O14  1  0.880  0.307  0.307  1.0
[/CIF]
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The structure described by Hg6Si2O7 crystallizes in the monoclinic C2/m space group. There are two inequivalent Hg sites. In the first Hg site, Hg(1) is bonded in a 3-coordinate geometry to one O(3) and two equivalent O(2) atoms. In the second Hg site, Hg(2) is bonded in a single-bond geometry to one O(3) atom. Si(1) is bonded to one O(1), one O(3), and two equivalent O(2) atoms to form corner-sharing SiO4 tetrahedra. There are three inequivalent O sites. In the first O site, O(1) is bonded in a linear geometry to two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Hg(1) and one Si(1) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Hg(2), two equivalent Hg(1), and one Si(1) atom. is represented by the CIF card [CIF]
data_Si2Hg6O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.104
_cell_length_b   7.054
_cell_length_c   7.054
_cell_angle_alpha   65.348
_cell_angle_beta   71.965
_cell_angle_gamma   71.965
_symmetry_Int_Tables_number   1
_cell_volume   256.728
_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
  Si  Si0  1  0.102  0.353  0.353  1.0
  Si  Si1  1  0.898  0.647  0.647  1.0
  Hg  Hg2  1  0.418  0.876  0.356  1.0
  Hg  Hg3  1  0.582  0.644  0.124  1.0
  Hg  Hg4  1  0.582  0.124  0.644  1.0
  Hg  Hg5  1  0.418  0.356  0.876  1.0
  Hg  Hg6  1  0.047  0.885  0.885  1.0
  Hg  Hg7  1  0.953  0.115  0.115  1.0
  O  O8  1  0.000  0.500  0.500  1.0
  O  O9  1  0.261  0.130  0.484  1.0
  O  O10  1  0.739  0.516  0.870  1.0
  O  O11  1  0.739  0.870  0.516  1.0
  O  O12  1  0.261  0.484  0.130  1.0
  O  O13  1  0.120  0.693  0.693  1.0
  O  O14  1  0.880  0.307  0.307  1.0
[/CIF]
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