The material structure described by Si5O8 crystallizes in the triclinic P1 space group. There are ten inequivalent Si sites. In the first Si site, Si(1) is bonded in a tetrahedral geometry to one O(1), one O(10), one O(11), and one O(3) atom. In the second Si site, Si(2) is bonded to one O(12), one O(14), one O(2), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded in a trigonal non-coplanar geometry to one O(10), one O(13), and one O(15) atom. In the fourth Si site, Si(4) is bonded in a water-like geometry to one O(14) and one O(4) atom. In the fifth Si site, Si(5) is bonded in a distorted trigonal non-coplanar geometry to one O(6), one O(7), and one O(8) atom. In the sixth Si site, Si(6) is bonded to one O(12), one O(16), one O(4), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the seventh Si site, Si(7) is bonded in a trigonal non-coplanar geometry to one O(11), one O(15), and one O(5) atom. In the eighth Si site, Si(8) is bonded in a tetrahedral geometry to one O(13), one O(5), one O(7), and one O(8) atom. In the ninth Si site, Si(9) is bonded in a water-like geometry to one O(16) and one O(2) atom. In the tenth Si site, Si(10) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(3), and one O(9) atom. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in an L-shaped geometry to one Si(1) and one Si(10) atom. In the second O site, O(2) is bonded in a linear geometry to one Si(2) and one Si(9) atom. In the third O site, O(3) is bonded in an L-shaped geometry to one Si(1) and one Si(10) atom. In the fourth O site, O(4) is bonded in a linear geometry to one Si(4) and one Si(6) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Si(7) and one Si(8) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(5) and one Si(6) atom. In the seventh O site, O(7) is bonded in an L-shaped geometry to one Si(5) and one Si(8) atom. In the eighth O site, O(8) is bonded in an L-shaped geometry to one Si(5) and one Si(8) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Si(10) and one Si(2) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Si(1) and one Si(3) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(7) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(6) atom. In the thirteenth O site, O(13) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(8) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(4) atom. In the fifteenth O site, O(15) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(7) atom. In the sixteenth O site, O(16) is bonded in a bent 150 degrees geometry to one Si(6) and one Si(9) atom. is represented by the CIF file [CIF]
data_Si5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.741
_cell_length_b   6.776
_cell_length_c   12.111
_cell_angle_alpha   102.221
_cell_angle_beta   90.463
_cell_angle_gamma   124.970
_symmetry_Int_Tables_number   1
_cell_volume   502.089
_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  0.707  0.440  0.610  1.0
  Si  Si1  1  0.472  0.225  0.941  1.0
  Si  Si2  1  0.789  0.162  0.414  1.0
  Si  Si3  1  0.119  0.285  0.850  1.0
  Si  Si4  1  0.481  0.842  0.282  1.0
  Si  Si5  1  0.247  0.770  0.055  1.0
  Si  Si6  1  0.632  0.841  0.589  1.0
  Si  Si7  1  0.264  0.564  0.393  1.0
  Si  Si8  1  0.835  0.713  0.144  1.0
  Si  Si9  1  0.652  0.163  0.722  1.0
  O  O10  1  0.864  0.445  0.710  1.0
  O  O11  1  0.641  0.479  0.040  1.0
  O  O12  1  0.491  0.189  0.638  1.0
  O  O13  1  0.189  0.531  0.953  1.0
  O  O14  1  0.382  0.629  0.522  1.0
  O  O15  1  0.442  0.851  0.152  1.0
  O  O16  1  0.296  0.814  0.366  1.0
  O  O17  1  0.414  0.562  0.294  1.0
  O  O18  1  0.600  0.153  0.852  1.0
  O  O19  1  0.760  0.377  0.483  1.0
  O  O20  1  0.709  0.687  0.634  1.0
  O  O21  1  0.326  0.001  0.000  1.0
  O  O22  1  0.019  0.313  0.367  1.0
  O  O23  1  0.315  0.256  0.869  1.0
  O  O24  1  0.783  0.000  0.501  1.0
  O  O25  1  0.042  0.707  0.116  1.0
[/CIF]
.
The material structure described by Si5O8 crystallizes in the triclinic P1 space group. There are ten inequivalent Si sites. In the first Si site, Si(1) is bonded in a tetrahedral geometry to one O(1), one O(10), one O(11), and one O(3) atom. In the second Si site, Si(2) is bonded to one O(12), one O(14), one O(2), and one O(9) atom to form corner-sharing SiO4 tetrahedra. In the third Si site, Si(3) is bonded in a trigonal non-coplanar geometry to one O(10), one O(13), and one O(15) atom. In the fourth Si site, Si(4) is bonded in a water-like geometry to one O(14) and one O(4) atom. In the fifth Si site, Si(5) is bonded in a distorted trigonal non-coplanar geometry to one O(6), one O(7), and one O(8) atom. In the sixth Si site, Si(6) is bonded to one O(12), one O(16), one O(4), and one O(6) atom to form corner-sharing SiO4 tetrahedra. In the seventh Si site, Si(7) is bonded in a trigonal non-coplanar geometry to one O(11), one O(15), and one O(5) atom. In the eighth Si site, Si(8) is bonded in a tetrahedral geometry to one O(13), one O(5), one O(7), and one O(8) atom. In the ninth Si site, Si(9) is bonded in a water-like geometry to one O(16) and one O(2) atom. In the tenth Si site, Si(10) is bonded in a distorted trigonal non-coplanar geometry to one O(1), one O(3), and one O(9) atom. There are sixteen inequivalent O sites. In the first O site, O(1) is bonded in an L-shaped geometry to one Si(1) and one Si(10) atom. In the second O site, O(2) is bonded in a linear geometry to one Si(2) and one Si(9) atom. In the third O site, O(3) is bonded in an L-shaped geometry to one Si(1) and one Si(10) atom. In the fourth O site, O(4) is bonded in a linear geometry to one Si(4) and one Si(6) atom. In the fifth O site, O(5) is bonded in a bent 120 degrees geometry to one Si(7) and one Si(8) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to one Si(5) and one Si(6) atom. In the seventh O site, O(7) is bonded in an L-shaped geometry to one Si(5) and one Si(8) atom. In the eighth O site, O(8) is bonded in an L-shaped geometry to one Si(5) and one Si(8) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Si(10) and one Si(2) atom. In the tenth O site, O(10) is bonded in a bent 120 degrees geometry to one Si(1) and one Si(3) atom. In the eleventh O site, O(11) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(7) atom. In the twelfth O site, O(12) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(6) atom. In the thirteenth O site, O(13) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(8) atom. In the fourteenth O site, O(14) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(4) atom. In the fifteenth O site, O(15) is bonded in a bent 150 degrees geometry to one Si(3) and one Si(7) atom. In the sixteenth O site, O(16) is bonded in a bent 150 degrees geometry to one Si(6) and one Si(9) atom. is represented by the CIF file [CIF]
data_Si5O8
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.741
_cell_length_b   6.776
_cell_length_c   12.111
_cell_angle_alpha   102.221
_cell_angle_beta   90.463
_cell_angle_gamma   124.970
_symmetry_Int_Tables_number   1
_cell_volume   502.089
_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  0.707  0.440  0.610  1.0
  Si  Si1  1  0.472  0.225  0.941  1.0
  Si  Si2  1  0.789  0.162  0.414  1.0
  Si  Si3  1  0.119  0.285  0.850  1.0
  Si  Si4  1  0.481  0.842  0.282  1.0
  Si  Si5  1  0.247  0.770  0.055  1.0
  Si  Si6  1  0.632  0.841  0.589  1.0
  Si  Si7  1  0.264  0.564  0.393  1.0
  Si  Si8  1  0.835  0.713  0.144  1.0
  Si  Si9  1  0.652  0.163  0.722  1.0
  O  O10  1  0.864  0.445  0.710  1.0
  O  O11  1  0.641  0.479  0.040  1.0
  O  O12  1  0.491  0.189  0.638  1.0
  O  O13  1  0.189  0.531  0.953  1.0
  O  O14  1  0.382  0.629  0.522  1.0
  O  O15  1  0.442  0.851  0.152  1.0
  O  O16  1  0.296  0.814  0.366  1.0
  O  O17  1  0.414  0.562  0.294  1.0
  O  O18  1  0.600  0.153  0.852  1.0
  O  O19  1  0.760  0.377  0.483  1.0
  O  O20  1  0.709  0.687  0.634  1.0
  O  O21  1  0.326  0.001  0.000  1.0
  O  O22  1  0.019  0.313  0.367  1.0
  O  O23  1  0.315  0.256  0.869  1.0
  O  O24  1  0.783  0.000  0.501  1.0
  O  O25  1  0.042  0.707  0.116  1.0
[/CIF]
.