The compound described by CaScSi3HO9 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(6), and two equivalent O(1) atoms. Sc(1) is bonded to one O(1), one O(3), one O(5), one O(6), and two equivalent O(2) atoms to form ScO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, corners with three equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Sc(1)O6 octahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(4), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Sc(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. In the second Si site, Si(2) is bonded to one O(2), one O(5), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with three equivalent Sc(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-62°. In the third Si site, Si(3) is bonded to one O(3), one O(6), one O(8), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent Sc(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, and  a cornercorner with one Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. H(1) is bonded in a distorted linear geometry to one O(4) and one O(5) atom. There are nine inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1), one Sc(1), and one Si(1) atom to form distorted edge-sharing OCa2ScSi tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Sc(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Sc(1), and one Si(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Si(1), and one H(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Sc(1), one Si(2), and one H(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(1), one Sc(1), and one Si(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the ninth O site, O(9) is bonded in a bent 120 degrees geometry to one Si(1) and one Si(3) atom. is represented by the CIF card [CIF]
data_CaScSi3HO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.867
_cell_length_b   7.141
_cell_length_c   7.586
_cell_angle_alpha   104.421
_cell_angle_beta   93.607
_cell_angle_gamma   91.837
_symmetry_Int_Tables_number   1
_cell_volume   359.097
_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  0.343  0.915  0.668  1.0
  Ca  Ca1  1  0.657  0.085  0.332  1.0
  Sc  Sc2  1  0.351  0.406  0.643  1.0
  Sc  Sc3  1  0.649  0.594  0.357  1.0
  Si  Si4  1  0.176  0.090  0.259  1.0
  Si  Si5  1  0.824  0.910  0.741  1.0
  Si  Si6  1  0.143  0.524  0.278  1.0
  Si  Si7  1  0.857  0.476  0.722  1.0
  Si  Si8  1  0.366  0.740  0.046  1.0
  Si  Si9  1  0.634  0.260  0.954  1.0
  H  H10  1  0.971  0.839  0.305  1.0
  H  H11  1  0.029  0.161  0.695  1.0
  O  O12  1  0.666  0.872  0.563  1.0
  O  O13  1  0.334  0.128  0.437  1.0
  O  O14  1  0.672  0.420  0.562  1.0
  O  O15  1  0.328  0.580  0.438  1.0
  O  O16  1  0.439  0.240  0.816  1.0
  O  O17  1  0.561  0.760  0.184  1.0
  O  O18  1  0.973  0.977  0.290  1.0
  O  O19  1  0.027  0.023  0.710  1.0
  O  O20  1  0.946  0.631  0.347  1.0
  O  O21  1  0.054  0.369  0.653  1.0
  O  O22  1  0.395  0.674  0.828  1.0
  O  O23  1  0.605  0.326  0.172  1.0
  O  O24  1  0.102  0.288  0.216  1.0
  O  O25  1  0.898  0.712  0.784  1.0
  O  O26  1  0.205  0.595  0.099  1.0
  O  O27  1  0.795  0.405  0.901  1.0
  O  O28  1  0.281  0.962  0.081  1.0
  O  O29  1  0.719  0.038  0.919  1.0
[/CIF]
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The compound described by CaScSi3HO9 crystallizes in the triclinic P-1 space group. Ca(1) is bonded in a 6-coordinate geometry to one O(2), one O(3), one O(4), one O(6), and two equivalent O(1) atoms. Sc(1) is bonded to one O(1), one O(3), one O(5), one O(6), and two equivalent O(2) atoms to form ScO6 octahedra that share  a cornercorner with one Si(1)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, corners with three equivalent Si(2)O4 tetrahedra, and  an edgeedge with one Sc(1)O6 octahedra. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(1), one O(4), one O(7), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Sc(1)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles are 60°. In the second Si site, Si(2) is bonded to one O(2), one O(5), one O(7), and one O(8) atom to form SiO4 tetrahedra that share corners with three equivalent Sc(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, and  a cornercorner with one Si(3)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 35-62°. In the third Si site, Si(3) is bonded to one O(3), one O(6), one O(8), and one O(9) atom to form SiO4 tetrahedra that share corners with two equivalent Sc(1)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra, and  a cornercorner with one Si(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 49°. H(1) is bonded in a distorted linear geometry to one O(4) and one O(5) atom. There are nine inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Ca(1), one Sc(1), and one Si(1) atom to form distorted edge-sharing OCa2ScSi tetrahedra. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ca(1), two equivalent Sc(1), and one Si(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Ca(1), one Sc(1), and one Si(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to one Ca(1), one Si(1), and one H(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal non-coplanar geometry to one Sc(1), one Si(2), and one H(1) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ca(1), one Sc(1), and one Si(3) atom. In the seventh O site, O(7) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the eighth O site, O(8) is bonded in a bent 150 degrees geometry to one Si(2) and one Si(3) atom. In the ninth O site, O(9) is bonded in a bent 120 degrees geometry to one Si(1) and one Si(3) atom. is represented by the CIF card [CIF]
data_CaScSi3HO9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.867
_cell_length_b   7.141
_cell_length_c   7.586
_cell_angle_alpha   104.421
_cell_angle_beta   93.607
_cell_angle_gamma   91.837
_symmetry_Int_Tables_number   1
_cell_volume   359.097
_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  0.343  0.915  0.668  1.0
  Ca  Ca1  1  0.657  0.085  0.332  1.0
  Sc  Sc2  1  0.351  0.406  0.643  1.0
  Sc  Sc3  1  0.649  0.594  0.357  1.0
  Si  Si4  1  0.176  0.090  0.259  1.0
  Si  Si5  1  0.824  0.910  0.741  1.0
  Si  Si6  1  0.143  0.524  0.278  1.0
  Si  Si7  1  0.857  0.476  0.722  1.0
  Si  Si8  1  0.366  0.740  0.046  1.0
  Si  Si9  1  0.634  0.260  0.954  1.0
  H  H10  1  0.971  0.839  0.305  1.0
  H  H11  1  0.029  0.161  0.695  1.0
  O  O12  1  0.666  0.872  0.563  1.0
  O  O13  1  0.334  0.128  0.437  1.0
  O  O14  1  0.672  0.420  0.562  1.0
  O  O15  1  0.328  0.580  0.438  1.0
  O  O16  1  0.439  0.240  0.816  1.0
  O  O17  1  0.561  0.760  0.184  1.0
  O  O18  1  0.973  0.977  0.290  1.0
  O  O19  1  0.027  0.023  0.710  1.0
  O  O20  1  0.946  0.631  0.347  1.0
  O  O21  1  0.054  0.369  0.653  1.0
  O  O22  1  0.395  0.674  0.828  1.0
  O  O23  1  0.605  0.326  0.172  1.0
  O  O24  1  0.102  0.288  0.216  1.0
  O  O25  1  0.898  0.712  0.784  1.0
  O  O26  1  0.205  0.595  0.099  1.0
  O  O27  1  0.795  0.405  0.901  1.0
  O  O28  1  0.281  0.962  0.081  1.0
  O  O29  1  0.719  0.038  0.919  1.0
[/CIF]
.