The material structure described by Zn4Si2O7(OH)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form ZnO4 tetrahedra that share  a cornercorner with one Zn(1)O4 tetrahedra, corners with three equivalent Zn(2)O4 tetrahedra, and corners with three equivalent Si(1)O4 tetrahedra. In the second Zn site, Zn(2) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form ZnO4 tetrahedra that share  a cornercorner with one Zn(2)O4 tetrahedra, corners with three equivalent Zn(1)O4 tetrahedra, and corners with three equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with three equivalent Zn(1)O4 tetrahedra, and corners with three equivalent Zn(2)O4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(4) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(5) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Zn(1), one Zn(2), and one Si(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Zn(1), one Zn(2), and one Si(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Zn(1), one Zn(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Zn(1) and one H(1) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Zn(2) and one H(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Zn4Si2H2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.348
_cell_length_b   7.348
_cell_length_c   5.200
_cell_angle_alpha   69.432
_cell_angle_beta   69.432
_cell_angle_gamma   97.033
_symmetry_Int_Tables_number   1
_cell_volume   236.268
_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
  Zn  Zn0  1  0.368  0.055  0.789  1.0
  Zn  Zn1  1  0.632  0.954  0.200  1.0
  Zn  Zn2  1  0.954  0.632  0.200  1.0
  Zn  Zn3  1  0.055  0.368  0.789  1.0
  Si  Si4  1  0.145  0.858  0.506  1.0
  Si  Si5  1  0.858  0.145  0.506  1.0
  H  H6  1  0.434  0.434  0.594  1.0
  H  H7  1  0.672  0.672  0.580  1.0
  O  O8  1  0.163  0.842  0.192  1.0
  O  O9  1  0.842  0.163  0.192  1.0
  O  O10  1  0.368  0.958  0.476  1.0
  O  O11  1  0.634  0.035  0.795  1.0
  O  O12  1  0.035  0.634  0.795  1.0
  O  O13  1  0.958  0.368  0.476  1.0
  O  O14  1  0.316  0.316  0.732  1.0
  O  O15  1  0.687  0.687  0.379  1.0
  O  O16  1  1.000  1.000  0.596  1.0
[/CIF]
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The material structure described by Zn4Si2O7(OH)2 crystallizes in the monoclinic Cm space group. There are two inequivalent Zn sites. In the first Zn site, Zn(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form ZnO4 tetrahedra that share  a cornercorner with one Zn(1)O4 tetrahedra, corners with three equivalent Zn(2)O4 tetrahedra, and corners with three equivalent Si(1)O4 tetrahedra. In the second Zn site, Zn(2) is bonded to one O(1), one O(2), one O(3), and one O(5) atom to form ZnO4 tetrahedra that share  a cornercorner with one Zn(2)O4 tetrahedra, corners with three equivalent Zn(1)O4 tetrahedra, and corners with three equivalent Si(1)O4 tetrahedra. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with three equivalent Zn(1)O4 tetrahedra, and corners with three equivalent Zn(2)O4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(4) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(5) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Zn(1), one Zn(2), and one Si(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Zn(1), one Zn(2), and one Si(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Zn(1), one Zn(2), and one Si(1) atom. In the fourth O site, O(4) is bonded in a trigonal planar geometry to two equivalent Zn(1) and one H(1) atom. In the fifth O site, O(5) is bonded in a distorted single-bond geometry to two equivalent Zn(2) and one H(2) atom. In the sixth O site, O(6) is bonded in a bent 150 degrees geometry to two equivalent Si(1) atoms. is represented by the CIF card [CIF]
data_Zn4Si2H2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.348
_cell_length_b   7.348
_cell_length_c   5.200
_cell_angle_alpha   69.432
_cell_angle_beta   69.432
_cell_angle_gamma   97.033
_symmetry_Int_Tables_number   1
_cell_volume   236.268
_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
  Zn  Zn0  1  0.368  0.055  0.789  1.0
  Zn  Zn1  1  0.632  0.954  0.200  1.0
  Zn  Zn2  1  0.954  0.632  0.200  1.0
  Zn  Zn3  1  0.055  0.368  0.789  1.0
  Si  Si4  1  0.145  0.858  0.506  1.0
  Si  Si5  1  0.858  0.145  0.506  1.0
  H  H6  1  0.434  0.434  0.594  1.0
  H  H7  1  0.672  0.672  0.580  1.0
  O  O8  1  0.163  0.842  0.192  1.0
  O  O9  1  0.842  0.163  0.192  1.0
  O  O10  1  0.368  0.958  0.476  1.0
  O  O11  1  0.634  0.035  0.795  1.0
  O  O12  1  0.035  0.634  0.795  1.0
  O  O13  1  0.958  0.368  0.476  1.0
  O  O14  1  0.316  0.316  0.732  1.0
  O  O15  1  0.687  0.687  0.379  1.0
  O  O16  1  1.000  1.000  0.596  1.0
[/CIF]
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