The crystal structure described by Si2H2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(2), one O(4), one O(5), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(10), one O(2), one O(3), and one O(6) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(7) and one O(9) atom. In the third H site, H(3) is bonded in a linear geometry to one O(8) and one O(9) atom. In the fourth H site, H(4) is bonded in a linear geometry to one O(10) and one O(8) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Si(1), one Si(2), and one H(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(4) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(4) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Si(1) and one H(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Si(2), one H(3), and one H(4) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Si(3), one H(2), and one H(3) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Si(4) and one H(4) atom. is represented by the CIF card [CIF]
data_Si2H2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.095
_cell_length_b   6.118
_cell_length_c   8.485
_cell_angle_alpha   109.355
_cell_angle_beta   106.314
_cell_angle_gamma   93.545
_symmetry_Int_Tables_number   1
_cell_volume   235.964
_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
  Si  Si0  1  0.658  0.491  0.215  1.0
  Si  Si1  1  0.421  0.498  0.797  1.0
  Si  Si2  1  0.946  0.808  0.819  1.0
  Si  Si3  1  0.122  0.179  0.205  1.0
  H  H4  1  0.812  0.449  0.983  1.0
  H  H5  1  0.756  0.828  0.458  1.0
  H  H6  1  0.086  0.062  0.686  1.0
  H  H7  1  0.230  0.129  0.474  1.0
  O  O8  1  0.639  0.492  0.003  1.0
  O  O9  1  0.943  0.994  0.008  1.0
  O  O10  1  0.943  0.391  0.261  1.0
  O  O11  1  0.665  0.608  0.741  1.0
  O  O12  1  0.223  0.684  0.861  1.0
  O  O13  1  0.390  0.306  0.177  1.0
  O  O14  1  0.661  0.757  0.328  1.0
  O  O15  1  0.277  0.239  0.677  1.0
  O  O16  1  0.934  0.926  0.673  1.0
  O  O17  1  0.195  0.050  0.342  1.0
[/CIF]
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The crystal structure described by Si2H2O5 crystallizes in the triclinic P1 space group. There are four inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(3), one O(6), and one O(7) atom to form corner-sharing SiO4 tetrahedra. In the second Si site, Si(2) is bonded to one O(1), one O(4), one O(5), and one O(8) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded to one O(2), one O(4), one O(5), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the fourth Si site, Si(4) is bonded to one O(10), one O(2), one O(3), and one O(6) atom to form corner-sharing SiO4 tetrahedra. There are four inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a distorted single-bond geometry to one O(7) and one O(9) atom. In the third H site, H(3) is bonded in a linear geometry to one O(8) and one O(9) atom. In the fourth H site, H(4) is bonded in a linear geometry to one O(10) and one O(8) atom. There are ten inequivalent O sites. In the first O site, O(1) is bonded in a 3-coordinate geometry to one Si(1), one Si(2), and one H(1) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(4) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(4) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(4) atom. In the seventh O site, O(7) is bonded in a bent 120 degrees geometry to one Si(1) and one H(2) atom. In the eighth O site, O(8) is bonded in a distorted trigonal planar geometry to one Si(2), one H(3), and one H(4) atom. In the ninth O site, O(9) is bonded in a 3-coordinate geometry to one Si(3), one H(2), and one H(3) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Si(4) and one H(4) atom. is represented by the CIF card [CIF]
data_Si2H2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.095
_cell_length_b   6.118
_cell_length_c   8.485
_cell_angle_alpha   109.355
_cell_angle_beta   106.314
_cell_angle_gamma   93.545
_symmetry_Int_Tables_number   1
_cell_volume   235.964
_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
  Si  Si0  1  0.658  0.491  0.215  1.0
  Si  Si1  1  0.421  0.498  0.797  1.0
  Si  Si2  1  0.946  0.808  0.819  1.0
  Si  Si3  1  0.122  0.179  0.205  1.0
  H  H4  1  0.812  0.449  0.983  1.0
  H  H5  1  0.756  0.828  0.458  1.0
  H  H6  1  0.086  0.062  0.686  1.0
  H  H7  1  0.230  0.129  0.474  1.0
  O  O8  1  0.639  0.492  0.003  1.0
  O  O9  1  0.943  0.994  0.008  1.0
  O  O10  1  0.943  0.391  0.261  1.0
  O  O11  1  0.665  0.608  0.741  1.0
  O  O12  1  0.223  0.684  0.861  1.0
  O  O13  1  0.390  0.306  0.177  1.0
  O  O14  1  0.661  0.757  0.328  1.0
  O  O15  1  0.277  0.239  0.677  1.0
  O  O16  1  0.934  0.926  0.673  1.0
  O  O17  1  0.195  0.050  0.342  1.0
[/CIF]
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