The compound described by CaAlSiO4OH is Esseneite-derived structured and crystallizes in the orthorhombic P2_12_12_1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. Al(1) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(3) 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(2), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with four equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 40-57°. H(1) is bonded in a linear geometry to one O(1) and one O(4) atom. There are five inequivalent O sites. In the first O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Al(1), and one Si(1) atom. In the second O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Al(1), and one H(1) atom. In the third O site, O(2) is bonded to two equivalent Ca(1), one Al(1), and one Si(1) atom to form distorted OCa2AlSi trigonal pyramids that share corners with two equivalent O(2)Ca2AlSi trigonal pyramids, corners with three equivalent O(3)CaAl2Si trigonal pyramids, and  an edgeedge with one O(3)CaAl2Si trigonal pyramid. In the fourth O site, O(3) is bonded to one Ca(1), two equivalent Al(1), and one Si(1) atom to form distorted OCaAl2Si trigonal pyramids that share corners with two equivalent O(3)CaAl2Si trigonal pyramids, corners with three equivalent O(2)Ca2AlSi trigonal pyramids, and  an edgeedge with one O(2)Ca2AlSi trigonal pyramid. In the fifth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Si(1), and one H(1) atom. is represented by the CIF card [CIF]
data_CaAlSiHO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.752
_cell_length_b   7.120
_cell_length_c   8.605
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   352.382
_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  0.470  0.636  0.164  1.0
  Ca  Ca1  1  0.970  0.864  0.836  1.0
  Ca  Ca2  1  0.530  0.136  0.336  1.0
  Ca  Ca3  1  0.030  0.364  0.664  1.0
  Al  Al4  1  0.243  0.238  0.005  1.0
  Al  Al5  1  0.743  0.262  0.995  1.0
  Al  Al6  1  0.257  0.762  0.505  1.0
  Al  Al7  1  0.757  0.738  0.495  1.0
  Si  Si8  1  0.988  0.379  0.310  1.0
  Si  Si9  1  0.012  0.879  0.190  1.0
  Si  Si10  1  0.488  0.121  0.690  1.0
  Si  Si11  1  0.512  0.621  0.810  1.0
  H  H12  1  0.480  0.477  0.493  1.0
  H  H13  1  0.980  0.023  0.507  1.0
  H  H14  1  0.520  0.977  0.007  1.0
  H  H15  1  0.020  0.523  0.993  1.0
  O  O16  1  0.494  0.604  0.436  1.0
  O  O17  1  0.994  0.896  0.564  1.0
  O  O18  1  0.506  0.104  0.064  1.0
  O  O19  1  0.006  0.396  0.936  1.0
  O  O20  1  0.758  0.386  0.193  1.0
  O  O21  1  0.258  0.114  0.807  1.0
  O  O22  1  0.242  0.886  0.307  1.0
  O  O23  1  0.742  0.614  0.693  1.0
  O  O24  1  0.491  0.430  0.929  1.0
  O  O25  1  0.991  0.070  0.071  1.0
  O  O26  1  0.509  0.930  0.571  1.0
  O  O27  1  0.009  0.570  0.429  1.0
  O  O28  1  0.572  0.789  0.933  1.0
  O  O29  1  0.072  0.711  0.067  1.0
  O  O30  1  0.428  0.289  0.567  1.0
  O  O31  1  0.928  0.211  0.433  1.0
  O  O32  1  0.268  0.649  0.711  1.0
  O  O33  1  0.768  0.851  0.289  1.0
  O  O34  1  0.732  0.149  0.789  1.0
  O  O35  1  0.232  0.351  0.211  1.0
[/CIF]
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The compound described by CaAlSiO4OH is Esseneite-derived structured and crystallizes in the orthorhombic P2_12_12_1 space group. Ca(1) is bonded in a 8-coordinate geometry to one O(1), one O(3), two equivalent O(2), two equivalent O(4), and two equivalent O(5) atoms. Al(1) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(3) 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(2), one O(3), one O(4), and one O(5) atom to form SiO4 tetrahedra that share corners with four equivalent Al(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 40-57°. H(1) is bonded in a linear geometry to one O(1) and one O(4) atom. There are five inequivalent O sites. In the first O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Al(1), and one Si(1) atom. In the second O site, O(1) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Al(1), and one H(1) atom. In the third O site, O(2) is bonded to two equivalent Ca(1), one Al(1), and one Si(1) atom to form distorted OCa2AlSi trigonal pyramids that share corners with two equivalent O(2)Ca2AlSi trigonal pyramids, corners with three equivalent O(3)CaAl2Si trigonal pyramids, and  an edgeedge with one O(3)CaAl2Si trigonal pyramid. In the fourth O site, O(3) is bonded to one Ca(1), two equivalent Al(1), and one Si(1) atom to form distorted OCaAl2Si trigonal pyramids that share corners with two equivalent O(3)CaAl2Si trigonal pyramids, corners with three equivalent O(2)Ca2AlSi trigonal pyramids, and  an edgeedge with one O(2)Ca2AlSi trigonal pyramid. In the fifth O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Ca(1), one Si(1), and one H(1) atom. is represented by the CIF card [CIF]
data_CaAlSiHO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.752
_cell_length_b   7.120
_cell_length_c   8.605
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   352.382
_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  0.470  0.636  0.164  1.0
  Ca  Ca1  1  0.970  0.864  0.836  1.0
  Ca  Ca2  1  0.530  0.136  0.336  1.0
  Ca  Ca3  1  0.030  0.364  0.664  1.0
  Al  Al4  1  0.243  0.238  0.005  1.0
  Al  Al5  1  0.743  0.262  0.995  1.0
  Al  Al6  1  0.257  0.762  0.505  1.0
  Al  Al7  1  0.757  0.738  0.495  1.0
  Si  Si8  1  0.988  0.379  0.310  1.0
  Si  Si9  1  0.012  0.879  0.190  1.0
  Si  Si10  1  0.488  0.121  0.690  1.0
  Si  Si11  1  0.512  0.621  0.810  1.0
  H  H12  1  0.480  0.477  0.493  1.0
  H  H13  1  0.980  0.023  0.507  1.0
  H  H14  1  0.520  0.977  0.007  1.0
  H  H15  1  0.020  0.523  0.993  1.0
  O  O16  1  0.494  0.604  0.436  1.0
  O  O17  1  0.994  0.896  0.564  1.0
  O  O18  1  0.506  0.104  0.064  1.0
  O  O19  1  0.006  0.396  0.936  1.0
  O  O20  1  0.758  0.386  0.193  1.0
  O  O21  1  0.258  0.114  0.807  1.0
  O  O22  1  0.242  0.886  0.307  1.0
  O  O23  1  0.742  0.614  0.693  1.0
  O  O24  1  0.491  0.430  0.929  1.0
  O  O25  1  0.991  0.070  0.071  1.0
  O  O26  1  0.509  0.930  0.571  1.0
  O  O27  1  0.009  0.570  0.429  1.0
  O  O28  1  0.572  0.789  0.933  1.0
  O  O29  1  0.072  0.711  0.067  1.0
  O  O30  1  0.428  0.289  0.567  1.0
  O  O31  1  0.928  0.211  0.433  1.0
  O  O32  1  0.268  0.649  0.711  1.0
  O  O33  1  0.768  0.851  0.289  1.0
  O  O34  1  0.732  0.149  0.789  1.0
  O  O35  1  0.232  0.351  0.211  1.0
[/CIF]
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