The material described by CaH2SiO4 crystallizes in the orthorhombic Fdd2 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(5), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(2) and one O(5) atom. In the second H site, H(2) is bonded in a distorted 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 linear geometry to two equivalent Ca(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Si(1), and one H(1) atom. In the third O site, O(3) is bonded to two equivalent Ca(1), one Si(1), and one H(2) atom to form distorted corner-sharing OCa2SiH tetrahedra. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Ca(1), one Si(1), and one H(2) atom. In the fifth O site, O(5) is bonded in a water-like geometry to two equivalent Ca(1) and two equivalent H(1) atoms. is represented by the CIF card [CIF]
data_CaSi(HO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.054
_cell_length_b   6.399
_cell_length_c   10.417
_cell_angle_alpha   82.099
_cell_angle_beta   73.106
_cell_angle_gamma   61.770
_symmetry_Int_Tables_number   1
_cell_volume   340.219
_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  0.668  0.825  0.346  1.0
  Ca  Ca1  1  0.838  0.175  0.654  1.0
  Ca  Ca2  1  0.764  0.325  0.154  1.0
  Ca  Ca3  1  0.243  0.675  0.846  1.0
  Si  Si4  1  0.277  0.821  0.132  1.0
  Si  Si5  1  0.230  0.179  0.868  1.0
  Si  Si6  1  0.160  0.321  0.368  1.0
  Si  Si7  1  0.848  0.679  0.632  1.0
  H  H8  1  0.656  0.095  0.942  1.0
  H  H9  1  0.693  0.905  0.058  1.0
  H  H10  1  0.348  0.595  0.558  1.0
  H  H11  1  0.501  0.405  0.442  1.0
  H  H12  1  0.195  0.508  0.134  1.0
  H  H13  1  0.837  0.492  0.866  1.0
  H  H14  1  0.080  0.008  0.366  1.0
  H  H15  1  0.453  0.992  0.634  1.0
  O  O16  1  0.259  0.000  0.000  1.0
  O  O17  1  0.009  0.500  0.500  1.0
  O  O18  1  0.538  0.756  0.176  1.0
  O  O19  1  0.469  0.244  0.824  1.0
  O  O20  1  0.464  0.256  0.324  1.0
  O  O21  1  0.043  0.744  0.676  1.0
  O  O22  1  0.008  0.935  0.249  1.0
  O  O23  1  0.192  0.065  0.751  1.0
  O  O24  1  0.007  0.435  0.251  1.0
  O  O25  1  0.693  0.565  0.749  1.0
  O  O26  1  0.315  0.572  0.071  1.0
  O  O27  1  0.958  0.428  0.929  1.0
  O  O28  1  0.136  0.072  0.429  1.0
  O  O29  1  0.637  0.928  0.571  1.0
  O  O30  1  0.777  0.000  0.000  1.0
  O  O31  1  0.527  0.500  0.500  1.0
[/CIF]
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The material described by CaH2SiO4 crystallizes in the orthorhombic Fdd2 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(5), two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms. Si(1) is bonded to one O(1), one O(2), one O(3), and one O(4) atom to form corner-sharing SiO4 tetrahedra. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(2) and one O(5) atom. In the second H site, H(2) is bonded in a distorted 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 linear geometry to two equivalent Ca(1) and two equivalent Si(1) atoms. In the second O site, O(2) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Si(1), and one H(1) atom. In the third O site, O(3) is bonded to two equivalent Ca(1), one Si(1), and one H(2) atom to form distorted corner-sharing OCa2SiH tetrahedra. In the fourth O site, O(4) is bonded in a 2-coordinate geometry to two equivalent Ca(1), one Si(1), and one H(2) atom. In the fifth O site, O(5) is bonded in a water-like geometry to two equivalent Ca(1) and two equivalent H(1) atoms. is represented by the CIF card [CIF]
data_CaSi(HO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.054
_cell_length_b   6.399
_cell_length_c   10.417
_cell_angle_alpha   82.099
_cell_angle_beta   73.106
_cell_angle_gamma   61.770
_symmetry_Int_Tables_number   1
_cell_volume   340.219
_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  0.668  0.825  0.346  1.0
  Ca  Ca1  1  0.838  0.175  0.654  1.0
  Ca  Ca2  1  0.764  0.325  0.154  1.0
  Ca  Ca3  1  0.243  0.675  0.846  1.0
  Si  Si4  1  0.277  0.821  0.132  1.0
  Si  Si5  1  0.230  0.179  0.868  1.0
  Si  Si6  1  0.160  0.321  0.368  1.0
  Si  Si7  1  0.848  0.679  0.632  1.0
  H  H8  1  0.656  0.095  0.942  1.0
  H  H9  1  0.693  0.905  0.058  1.0
  H  H10  1  0.348  0.595  0.558  1.0
  H  H11  1  0.501  0.405  0.442  1.0
  H  H12  1  0.195  0.508  0.134  1.0
  H  H13  1  0.837  0.492  0.866  1.0
  H  H14  1  0.080  0.008  0.366  1.0
  H  H15  1  0.453  0.992  0.634  1.0
  O  O16  1  0.259  0.000  0.000  1.0
  O  O17  1  0.009  0.500  0.500  1.0
  O  O18  1  0.538  0.756  0.176  1.0
  O  O19  1  0.469  0.244  0.824  1.0
  O  O20  1  0.464  0.256  0.324  1.0
  O  O21  1  0.043  0.744  0.676  1.0
  O  O22  1  0.008  0.935  0.249  1.0
  O  O23  1  0.192  0.065  0.751  1.0
  O  O24  1  0.007  0.435  0.251  1.0
  O  O25  1  0.693  0.565  0.749  1.0
  O  O26  1  0.315  0.572  0.071  1.0
  O  O27  1  0.958  0.428  0.929  1.0
  O  O28  1  0.136  0.072  0.429  1.0
  O  O29  1  0.637  0.928  0.571  1.0
  O  O30  1  0.777  0.000  0.000  1.0
  O  O31  1  0.527  0.500  0.500  1.0
[/CIF]
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