The crystal structure described by CaH2SiO4 crystallizes in the orthorhombic Fdd2 space group. Ca(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form a mixture of corner and edge-sharing CaO6 octahedra. The corner-sharing octahedral tilt angles are 11°. Si(1) is bonded in a bent 120 degrees geometry to one O(2) and one O(3) atom. 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 linear geometry to one O(3) and one O(4) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to two equivalent Ca(1) and one O(5) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ca(1) and one Si(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(1), one Si(1), and one H(2) atom. In the fourth O site, O(4) is bonded in a distorted water-like geometry to two equivalent Ca(1), one H(1), and one H(2) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one O(1) atom. is represented by the CIF card [CIF]
data_CaSi(HO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.512
_cell_length_b   9.566
_cell_length_c   15.542
_cell_angle_alpha   53.582
_cell_angle_beta   37.973
_cell_angle_gamma   88.446
_symmetry_Int_Tables_number   1
_cell_volume   419.204
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.435  0.110  0.150  1.0
  Ca  Ca1  1  0.110  0.435  0.305  1.0
  Ca  Ca2  1  0.100  0.945  0.815  1.0
  Ca  Ca3  1  0.945  0.100  0.140  1.0
  Si  Si4  1  0.368  0.604  0.395  1.0
  Si  Si5  1  0.604  0.368  0.633  1.0
  Si  Si6  1  0.855  0.617  0.882  1.0
  Si  Si7  1  0.617  0.855  0.646  1.0
  H  H8  1  0.673  0.343  0.430  1.0
  H  H9  1  0.343  0.673  0.553  1.0
  H  H10  1  0.820  0.697  0.577  1.0
  H  H11  1  0.697  0.820  0.907  1.0
  H  H12  1  0.247  0.723  0.672  1.0
  H  H13  1  0.723  0.247  0.359  1.0
  H  H14  1  0.578  0.891  0.003  1.0
  H  H15  1  0.891  0.578  0.527  1.0
  O  O16  1  0.954  0.954  0.046  1.0
  O  O17  1  0.204  0.204  0.296  1.0
  O  O18  1  0.947  0.586  0.749  1.0
  O  O19  1  0.586  0.947  0.717  1.0
  O  O20  1  0.501  0.533  0.303  1.0
  O  O21  1  0.533  0.501  0.664  1.0
  O  O22  1  0.448  0.837  0.195  1.0
  O  O23  1  0.837  0.448  0.520  1.0
  O  O24  1  0.055  0.730  0.802  1.0
  O  O25  1  0.730  0.055  0.413  1.0
  O  O26  1  0.356  0.697  0.600  1.0
  O  O27  1  0.697  0.356  0.347  1.0
  O  O28  1  0.650  0.903  0.894  1.0
  O  O29  1  0.903  0.650  0.553  1.0
  O  O30  1  0.586  0.586  0.414  1.0
  O  O31  1  0.836  0.836  0.664  1.0
[/CIF]
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The crystal structure described by CaH2SiO4 crystallizes in the orthorhombic Fdd2 space group. Ca(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(4) atoms to form a mixture of corner and edge-sharing CaO6 octahedra. The corner-sharing octahedral tilt angles are 11°. Si(1) is bonded in a bent 120 degrees geometry to one O(2) and one O(3) atom. 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 linear geometry to one O(3) and one O(4) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a T-shaped geometry to two equivalent Ca(1) and one O(5) atom. In the second O site, O(2) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Ca(1) and one Si(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ca(1), one Si(1), and one H(2) atom. In the fourth O site, O(4) is bonded in a distorted water-like geometry to two equivalent Ca(1), one H(1), and one H(2) atom. In the fifth O site, O(5) is bonded in a single-bond geometry to one O(1) atom. is represented by the CIF card [CIF]
data_CaSi(HO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.512
_cell_length_b   9.566
_cell_length_c   15.542
_cell_angle_alpha   53.582
_cell_angle_beta   37.973
_cell_angle_gamma   88.446
_symmetry_Int_Tables_number   1
_cell_volume   419.204
_cell_formula_units_Z   4
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
  Ca  Ca0  1  0.435  0.110  0.150  1.0
  Ca  Ca1  1  0.110  0.435  0.305  1.0
  Ca  Ca2  1  0.100  0.945  0.815  1.0
  Ca  Ca3  1  0.945  0.100  0.140  1.0
  Si  Si4  1  0.368  0.604  0.395  1.0
  Si  Si5  1  0.604  0.368  0.633  1.0
  Si  Si6  1  0.855  0.617  0.882  1.0
  Si  Si7  1  0.617  0.855  0.646  1.0
  H  H8  1  0.673  0.343  0.430  1.0
  H  H9  1  0.343  0.673  0.553  1.0
  H  H10  1  0.820  0.697  0.577  1.0
  H  H11  1  0.697  0.820  0.907  1.0
  H  H12  1  0.247  0.723  0.672  1.0
  H  H13  1  0.723  0.247  0.359  1.0
  H  H14  1  0.578  0.891  0.003  1.0
  H  H15  1  0.891  0.578  0.527  1.0
  O  O16  1  0.954  0.954  0.046  1.0
  O  O17  1  0.204  0.204  0.296  1.0
  O  O18  1  0.947  0.586  0.749  1.0
  O  O19  1  0.586  0.947  0.717  1.0
  O  O20  1  0.501  0.533  0.303  1.0
  O  O21  1  0.533  0.501  0.664  1.0
  O  O22  1  0.448  0.837  0.195  1.0
  O  O23  1  0.837  0.448  0.520  1.0
  O  O24  1  0.055  0.730  0.802  1.0
  O  O25  1  0.730  0.055  0.413  1.0
  O  O26  1  0.356  0.697  0.600  1.0
  O  O27  1  0.697  0.356  0.347  1.0
  O  O28  1  0.650  0.903  0.894  1.0
  O  O29  1  0.903  0.650  0.553  1.0
  O  O30  1  0.586  0.586  0.414  1.0
  O  O31  1  0.836  0.836  0.664  1.0
[/CIF]
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