The material structure described by (CaAl2Si2O9)2H2 crystallizes in the orthorhombic Cmcm space group. The structure consists of four 1333-74-0 atoms inside a CaAl2Si2O9 framework. In the CaAl2Si2O9 framework, Ca(1) is bonded in a 5-coordinate geometry to one O(3) and four equivalent O(1) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form AlO6 octahedra that share corners with four equivalent Si(1)O4 tetrahedra and edges with two equivalent Al(1)O6 octahedra. Si(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form SiO4 tetrahedra that share corners with four equivalent Al(1)O6 octahedra and  a cornercorner with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-62°. There are four inequivalent O sites. In the first O site, O(2) is bonded in a water-like geometry to two equivalent Al(1) atoms. In the second O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(1) and two equivalent Si(1) atoms. In the third O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Al(1) and one Si(1) atom. In the fourth O site, O(1) is bonded in a trigonal planar geometry to one Ca(1), one Al(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaAl2Si2HO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.349
_cell_length_b   5.349
_cell_length_c   13.033
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   113.981
_symmetry_Int_Tables_number   1
_cell_volume   340.756
_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
  Ca  Ca0  1  0.674  0.326  0.750  1.0
  Ca  Ca1  1  0.326  0.674  0.250  1.0
  Al  Al2  1  0.000  0.500  0.500  1.0
  Al  Al3  1  0.000  0.500  0.000  1.0
  Al  Al4  1  0.500  0.000  0.000  1.0
  Al  Al5  1  0.500  0.000  0.500  1.0
  Si  Si6  1  0.979  0.021  0.131  1.0
  Si  Si7  1  0.021  0.979  0.869  1.0
  Si  Si8  1  0.021  0.979  0.631  1.0
  Si  Si9  1  0.979  0.021  0.369  1.0
  H  H10  1  0.331  0.669  0.750  1.0
  H  H11  1  0.669  0.331  0.250  1.0
  O  O12  1  0.891  0.646  0.616  1.0
  O  O13  1  0.109  0.354  0.384  1.0
  O  O14  1  0.109  0.354  0.116  1.0
  O  O15  1  0.354  0.109  0.884  1.0
  O  O16  1  0.891  0.646  0.884  1.0
  O  O17  1  0.646  0.891  0.116  1.0
  O  O18  1  0.646  0.891  0.384  1.0
  O  O19  1  0.354  0.109  0.616  1.0
  O  O20  1  0.350  0.650  0.559  1.0
  O  O21  1  0.650  0.350  0.441  1.0
  O  O22  1  0.650  0.350  0.059  1.0
  O  O23  1  0.350  0.650  0.941  1.0
  O  O24  1  0.952  0.048  0.750  1.0
  O  O25  1  0.048  0.952  0.250  1.0
  O  O26  1  0.863  0.137  0.566  1.0
  O  O27  1  0.137  0.863  0.434  1.0
  O  O28  1  0.137  0.863  0.066  1.0
  O  O29  1  0.863  0.137  0.934  1.0
[/CIF]
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The material structure described by (CaAl2Si2O9)2H2 crystallizes in the orthorhombic Cmcm space group. The structure consists of four 1333-74-0 atoms inside a CaAl2Si2O9 framework. In the CaAl2Si2O9 framework, Ca(1) is bonded in a 5-coordinate geometry to one O(3) and four equivalent O(1) atoms. Al(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form AlO6 octahedra that share corners with four equivalent Si(1)O4 tetrahedra and edges with two equivalent Al(1)O6 octahedra. Si(1) is bonded to one O(3), one O(4), and two equivalent O(1) atoms to form SiO4 tetrahedra that share corners with four equivalent Al(1)O6 octahedra and  a cornercorner with one Si(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 48-62°. There are four inequivalent O sites. In the first O site, O(2) is bonded in a water-like geometry to two equivalent Al(1) atoms. In the second O site, O(3) is bonded in a distorted trigonal planar geometry to one Ca(1) and two equivalent Si(1) atoms. In the third O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Al(1) and one Si(1) atom. In the fourth O site, O(1) is bonded in a trigonal planar geometry to one Ca(1), one Al(1), and one Si(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_CaAl2Si2HO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.349
_cell_length_b   5.349
_cell_length_c   13.033
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   113.981
_symmetry_Int_Tables_number   1
_cell_volume   340.756
_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
  Ca  Ca0  1  0.674  0.326  0.750  1.0
  Ca  Ca1  1  0.326  0.674  0.250  1.0
  Al  Al2  1  0.000  0.500  0.500  1.0
  Al  Al3  1  0.000  0.500  0.000  1.0
  Al  Al4  1  0.500  0.000  0.000  1.0
  Al  Al5  1  0.500  0.000  0.500  1.0
  Si  Si6  1  0.979  0.021  0.131  1.0
  Si  Si7  1  0.021  0.979  0.869  1.0
  Si  Si8  1  0.021  0.979  0.631  1.0
  Si  Si9  1  0.979  0.021  0.369  1.0
  H  H10  1  0.331  0.669  0.750  1.0
  H  H11  1  0.669  0.331  0.250  1.0
  O  O12  1  0.891  0.646  0.616  1.0
  O  O13  1  0.109  0.354  0.384  1.0
  O  O14  1  0.109  0.354  0.116  1.0
  O  O15  1  0.354  0.109  0.884  1.0
  O  O16  1  0.891  0.646  0.884  1.0
  O  O17  1  0.646  0.891  0.116  1.0
  O  O18  1  0.646  0.891  0.384  1.0
  O  O19  1  0.354  0.109  0.616  1.0
  O  O20  1  0.350  0.650  0.559  1.0
  O  O21  1  0.650  0.350  0.441  1.0
  O  O22  1  0.650  0.350  0.059  1.0
  O  O23  1  0.350  0.650  0.941  1.0
  O  O24  1  0.952  0.048  0.750  1.0
  O  O25  1  0.048  0.952  0.250  1.0
  O  O26  1  0.863  0.137  0.566  1.0
  O  O27  1  0.137  0.863  0.434  1.0
  O  O28  1  0.137  0.863  0.066  1.0
  O  O29  1  0.863  0.137  0.934  1.0
[/CIF]
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