The structure described by Ca9Si6(WO7)4 crystallizes in the triclinic P-1 space group. There are five inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(6), and two equivalent O(14) atoms. In the second Ca site, Ca(2) is bonded to one O(10), one O(13), one O(2), one O(7), and two equivalent O(5) atoms to form distorted CaO6 octahedra that share  a cornercorner with one Ca(4)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, and  an edgeedge with one Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles are 70°. In the third Ca site, Ca(3) is bonded in a 6-coordinate geometry to one O(11), one O(13), one O(5), one O(7), and two equivalent O(2) atoms. In the fourth Ca site, Ca(4) is bonded to one O(10), one O(11), one O(14), one O(3), and two equivalent O(6) atoms to form CaO6 octahedra that share  a cornercorner with one Ca(2)O6 octahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  a cornercorner with one W(1)O5 trigonal bipyramid,  an edgeedge with one Ca(4)O6 octahedra, and  an edgeedge with one W(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 70°. In the fifth Ca site, Ca(5) is bonded in a linear geometry to two equivalent O(7) atoms. There are two inequivalent W sites. In the first W site, W(1) is bonded to one O(11), one O(12), one O(8), and two equivalent O(3) atoms to form WO5 trigonal bipyramids that share  a cornercorner with one Ca(4)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra,  an edgeedge with one Ca(4)O6 octahedra, and  an edgeedge with one W(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 19°. In the second W site, W(2) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(12), one O(13), and one O(8) atom. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(13), one O(4), one O(8), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Ca(2)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one W(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 66°. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Ca(2)O6 octahedra, corners with two equivalent Ca(4)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 43-60°. In the third Si site, Si(3) is bonded to one O(1), one O(14), one O(5), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Ca(4)O6 octahedra, corners with two equivalent Ca(2)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 range from 54-68°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ca(1), one Si(2), and one Si(3) atom. In the second O site, O(2) is bonded to one Ca(2), two equivalent Ca(3), and one Si(2) atom to form distorted OCa3Si tetrahedra that share corners with two equivalent O(11)Ca3W tetrahedra,  a cornercorner with one O(6)Ca3Si trigonal pyramid, and  an edgeedge with one O(2)Ca3Si tetrahedra. In the third O site, O(3) is bonded in a T-shaped geometry to one Ca(4) and two equivalent W(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(3), two equivalent Ca(2), and one Si(3) atom. In the sixth O site, O(6) is bonded to one Ca(1), two equivalent Ca(4), and one Si(2) atom to form distorted OCa3Si trigonal pyramids that share  a cornercorner with one O(2)Ca3Si tetrahedra, corners with three equivalent O(11)Ca3W tetrahedra, and  an edgeedge with one O(6)Ca3Si trigonal pyramid. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Ca(2), one Ca(3), and one Ca(5) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one W(1), one W(2), and one Si(1) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the tenth O site, O(10) is bonded in a distorted see-saw-like geometry to one Ca(1), one Ca(2), one Ca(4), and one W(2) atom. In the eleventh O site, O(11) is bonded to one Ca(1), one Ca(3), one Ca(4), and one W(1) atom to form distorted corner-sharing OCa3W tetrahedra. In the twelfth O site, O(12) is bonded in a distorted T-shaped geometry to one Ca(1), one W(1), and one W(2) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(3), one W(2), and one Si(1) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Ca(4), two equivalent Ca(1), and one Si(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca9Si6(WO7)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.517
_cell_length_b   10.136
_cell_length_c   10.359
_cell_angle_alpha   86.839
_cell_angle_beta   107.834
_cell_angle_gamma   107.028
_symmetry_Int_Tables_number   1
_cell_volume   717.922
_cell_formula_units_Z   1
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  0.793  0.850  0.460  1.0
  Ca  Ca1  1  0.207  0.150  0.540  1.0
  Ca  Ca2  1  0.662  0.113  0.920  1.0
  Ca  Ca3  1  0.338  0.887  0.080  1.0
  Ca  Ca4  1  0.888  0.838  0.089  1.0
  Ca  Ca5  1  0.112  0.162  0.911  1.0
  Ca  Ca6  1  0.299  0.838  0.445  1.0
  Ca  Ca7  1  0.701  0.162  0.555  1.0
  Ca  Ca8  1  0.000  0.500  0.000  1.0
  Si  Si9  1  0.415  0.663  0.854  1.0
  Si  Si10  1  0.585  0.337  0.146  1.0
  Si  Si11  1  0.741  0.856  0.748  1.0
  Si  Si12  1  0.259  0.144  0.252  1.0
  Si  Si13  1  0.158  0.869  0.742  1.0
  Si  Si14  1  0.842  0.131  0.258  1.0
  W  W15  1  0.888  0.577  0.387  1.0
  W  W16  1  0.112  0.423  0.613  1.0
  W  W17  1  0.494  0.359  0.784  1.0
  W  W18  1  0.506  0.641  0.216  1.0
  O  O19  1  0.918  0.807  0.720  1.0
  O  O20  1  0.082  0.193  0.280  1.0
  O  O21  1  0.826  0.970  0.872  1.0
  O  O22  1  0.174  0.030  0.128  1.0
  O  O23  1  0.847  0.392  0.495  1.0
  O  O24  1  0.153  0.608  0.505  1.0
  O  O25  1  0.605  0.715  0.800  1.0
  O  O26  1  0.395  0.285  0.200  1.0
  O  O27  1  0.278  0.985  0.864  1.0
  O  O28  1  0.722  0.015  0.136  1.0
  O  O29  1  0.625  0.907  0.603  1.0
  O  O30  1  0.375  0.093  0.397  1.0
  O  O31  1  0.067  0.718  0.046  1.0
  O  O32  1  0.933  0.282  0.954  1.0
  O  O33  1  0.327  0.496  0.818  1.0
  O  O34  1  0.673  0.504  0.182  1.0
  O  O35  1  0.242  0.732  0.776  1.0
  O  O36  1  0.758  0.268  0.224  1.0
  O  O37  1  0.454  0.793  0.292  1.0
  O  O38  1  0.546  0.207  0.708  1.0
  O  O39  1  0.951  0.768  0.317  1.0
  O  O40  1  0.049  0.232  0.683  1.0
  O  O41  1  0.644  0.597  0.406  1.0
  O  O42  1  0.356  0.403  0.594  1.0
  O  O43  1  0.485  0.703  0.017  1.0
  O  O44  1  0.515  0.297  0.983  1.0
  O  O45  1  0.158  0.922  0.590  1.0
  O  O46  1  0.842  0.078  0.410  1.0
[/CIF]
.
The structure described by Ca9Si6(WO7)4 crystallizes in the triclinic P-1 space group. There are five inequivalent Ca sites. In the first Ca site, Ca(1) is bonded in a 7-coordinate geometry to one O(1), one O(10), one O(11), one O(12), one O(6), and two equivalent O(14) atoms. In the second Ca site, Ca(2) is bonded to one O(10), one O(13), one O(2), one O(7), and two equivalent O(5) atoms to form distorted CaO6 octahedra that share  a cornercorner with one Ca(4)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra,  a cornercorner with one Si(2)O4 tetrahedra, corners with two equivalent Si(3)O4 tetrahedra, and  an edgeedge with one Ca(2)O6 octahedra. The corner-sharing octahedral tilt angles are 70°. In the third Ca site, Ca(3) is bonded in a 6-coordinate geometry to one O(11), one O(13), one O(5), one O(7), and two equivalent O(2) atoms. In the fourth Ca site, Ca(4) is bonded to one O(10), one O(11), one O(14), one O(3), and two equivalent O(6) atoms to form CaO6 octahedra that share  a cornercorner with one Ca(2)O6 octahedra,  a cornercorner with one Si(3)O4 tetrahedra, corners with two equivalent Si(2)O4 tetrahedra,  a cornercorner with one W(1)O5 trigonal bipyramid,  an edgeedge with one Ca(4)O6 octahedra, and  an edgeedge with one W(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 70°. In the fifth Ca site, Ca(5) is bonded in a linear geometry to two equivalent O(7) atoms. There are two inequivalent W sites. In the first W site, W(1) is bonded to one O(11), one O(12), one O(8), and two equivalent O(3) atoms to form WO5 trigonal bipyramids that share  a cornercorner with one Ca(4)O6 octahedra,  a cornercorner with one Si(1)O4 tetrahedra,  an edgeedge with one Ca(4)O6 octahedra, and  an edgeedge with one W(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 19°. In the second W site, W(2) is bonded in a distorted rectangular see-saw-like geometry to one O(10), one O(12), one O(13), and one O(8) atom. There are three inequivalent Si sites. In the first Si site, Si(1) is bonded to one O(13), one O(4), one O(8), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Ca(2)O6 octahedra,  a cornercorner with one Si(2)O4 tetrahedra,  a cornercorner with one Si(3)O4 tetrahedra, and  a cornercorner with one W(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles are 66°. In the second Si site, Si(2) is bonded to one O(1), one O(2), one O(4), and one O(6) atom to form SiO4 tetrahedra that share  a cornercorner with one Ca(2)O6 octahedra, corners with two equivalent Ca(4)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 43-60°. In the third Si site, Si(3) is bonded to one O(1), one O(14), one O(5), and one O(9) atom to form SiO4 tetrahedra that share  a cornercorner with one Ca(4)O6 octahedra, corners with two equivalent Ca(2)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 range from 54-68°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to one Ca(1), one Si(2), and one Si(3) atom. In the second O site, O(2) is bonded to one Ca(2), two equivalent Ca(3), and one Si(2) atom to form distorted OCa3Si tetrahedra that share corners with two equivalent O(11)Ca3W tetrahedra,  a cornercorner with one O(6)Ca3Si trigonal pyramid, and  an edgeedge with one O(2)Ca3Si tetrahedra. In the third O site, O(3) is bonded in a T-shaped geometry to one Ca(4) and two equivalent W(1) atoms. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(2) atom. In the fifth O site, O(5) is bonded in a 4-coordinate geometry to one Ca(3), two equivalent Ca(2), and one Si(3) atom. In the sixth O site, O(6) is bonded to one Ca(1), two equivalent Ca(4), and one Si(2) atom to form distorted OCa3Si trigonal pyramids that share  a cornercorner with one O(2)Ca3Si tetrahedra, corners with three equivalent O(11)Ca3W tetrahedra, and  an edgeedge with one O(6)Ca3Si trigonal pyramid. In the seventh O site, O(7) is bonded in a distorted trigonal planar geometry to one Ca(2), one Ca(3), and one Ca(5) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to one W(1), one W(2), and one Si(1) atom. In the ninth O site, O(9) is bonded in a bent 150 degrees geometry to one Si(1) and one Si(3) atom. In the tenth O site, O(10) is bonded in a distorted see-saw-like geometry to one Ca(1), one Ca(2), one Ca(4), and one W(2) atom. In the eleventh O site, O(11) is bonded to one Ca(1), one Ca(3), one Ca(4), and one W(1) atom to form distorted corner-sharing OCa3W tetrahedra. In the twelfth O site, O(12) is bonded in a distorted T-shaped geometry to one Ca(1), one W(1), and one W(2) atom. In the thirteenth O site, O(13) is bonded in a 4-coordinate geometry to one Ca(2), one Ca(3), one W(2), and one Si(1) atom. In the fourteenth O site, O(14) is bonded in a 4-coordinate geometry to one Ca(4), two equivalent Ca(1), and one Si(3) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ca9Si6(WO7)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.517
_cell_length_b   10.136
_cell_length_c   10.359
_cell_angle_alpha   86.839
_cell_angle_beta   107.834
_cell_angle_gamma   107.028
_symmetry_Int_Tables_number   1
_cell_volume   717.922
_cell_formula_units_Z   1
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  0.793  0.850  0.460  1.0
  Ca  Ca1  1  0.207  0.150  0.540  1.0
  Ca  Ca2  1  0.662  0.113  0.920  1.0
  Ca  Ca3  1  0.338  0.887  0.080  1.0
  Ca  Ca4  1  0.888  0.838  0.089  1.0
  Ca  Ca5  1  0.112  0.162  0.911  1.0
  Ca  Ca6  1  0.299  0.838  0.445  1.0
  Ca  Ca7  1  0.701  0.162  0.555  1.0
  Ca  Ca8  1  0.000  0.500  0.000  1.0
  Si  Si9  1  0.415  0.663  0.854  1.0
  Si  Si10  1  0.585  0.337  0.146  1.0
  Si  Si11  1  0.741  0.856  0.748  1.0
  Si  Si12  1  0.259  0.144  0.252  1.0
  Si  Si13  1  0.158  0.869  0.742  1.0
  Si  Si14  1  0.842  0.131  0.258  1.0
  W  W15  1  0.888  0.577  0.387  1.0
  W  W16  1  0.112  0.423  0.613  1.0
  W  W17  1  0.494  0.359  0.784  1.0
  W  W18  1  0.506  0.641  0.216  1.0
  O  O19  1  0.918  0.807  0.720  1.0
  O  O20  1  0.082  0.193  0.280  1.0
  O  O21  1  0.826  0.970  0.872  1.0
  O  O22  1  0.174  0.030  0.128  1.0
  O  O23  1  0.847  0.392  0.495  1.0
  O  O24  1  0.153  0.608  0.505  1.0
  O  O25  1  0.605  0.715  0.800  1.0
  O  O26  1  0.395  0.285  0.200  1.0
  O  O27  1  0.278  0.985  0.864  1.0
  O  O28  1  0.722  0.015  0.136  1.0
  O  O29  1  0.625  0.907  0.603  1.0
  O  O30  1  0.375  0.093  0.397  1.0
  O  O31  1  0.067  0.718  0.046  1.0
  O  O32  1  0.933  0.282  0.954  1.0
  O  O33  1  0.327  0.496  0.818  1.0
  O  O34  1  0.673  0.504  0.182  1.0
  O  O35  1  0.242  0.732  0.776  1.0
  O  O36  1  0.758  0.268  0.224  1.0
  O  O37  1  0.454  0.793  0.292  1.0
  O  O38  1  0.546  0.207  0.708  1.0
  O  O39  1  0.951  0.768  0.317  1.0
  O  O40  1  0.049  0.232  0.683  1.0
  O  O41  1  0.644  0.597  0.406  1.0
  O  O42  1  0.356  0.403  0.594  1.0
  O  O43  1  0.485  0.703  0.017  1.0
  O  O44  1  0.515  0.297  0.983  1.0
  O  O45  1  0.158  0.922  0.590  1.0
  O  O46  1  0.842  0.078  0.410  1.0
[/CIF]
.