The compound described by Sr3W2O9 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form distorted SrO5 trigonal bipyramids that share  a cornercorner with one W(2)O4 tetrahedra, corners with three equivalent W(1)O4 tetrahedra,  a cornercorner with one Sr(3)O5 trigonal bipyramid, and edges with two equivalent Sr(2)O6 octahedra. In the second Sr site, Sr(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form SrO6 octahedra that share corners with two equivalent Sr(2)O6 octahedra, corners with two equivalent W(1)O4 tetrahedra, corners with two equivalent W(2)O4 tetrahedra, edges with two equivalent Sr(1)O5 trigonal bipyramids, and edges with two equivalent Sr(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 62°. In the third Sr site, Sr(3) is bonded to one O(1), one O(5), one O(7), and two equivalent O(6) atoms to form distorted SrO5 trigonal bipyramids that share  a cornercorner with one W(1)O4 tetrahedra, corners with three equivalent W(2)O4 tetrahedra,  a cornercorner with one Sr(1)O5 trigonal bipyramid, and edges with two equivalent Sr(2)O6 octahedra. There are two inequivalent W sites. In the first W site, W(1) is bonded to one O(3), one O(5), and two equivalent O(2) atoms to form WO4 tetrahedra that share corners with two equivalent Sr(2)O6 octahedra,  a cornercorner with one Sr(3)O5 trigonal bipyramid, and corners with three equivalent Sr(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 48°. In the second W site, W(2) is bonded to one O(4), one O(7), and two equivalent O(6) atoms to form WO4 tetrahedra that share corners with two equivalent Sr(2)O6 octahedra,  a cornercorner with one Sr(1)O5 trigonal bipyramid, and corners with three equivalent Sr(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 43°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Sr(3), and two equivalent Sr(2) atoms to form corner-sharing OSr4 tetrahedra. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Sr(1), one Sr(2), and one W(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Sr(1) and one W(1) atom. In the fourth O site, O(4) is bonded in a linear geometry to one Sr(1) and one W(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Sr(3) and one W(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(2), one Sr(3), and one W(2) atom. In the seventh O site, O(7) is bonded in a linear geometry to one Sr(3) and one W(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3W2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.117
_cell_length_b   9.069
_cell_length_c   9.670
_cell_angle_alpha   62.850
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   633.416
_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
  Sr  Sr0  1  0.250  0.372  0.745  1.0
  Sr  Sr1  1  0.000  0.000  0.000  1.0
  Sr  Sr2  1  0.500  0.000  0.000  1.0
  Sr  Sr3  1  0.250  0.166  0.222  1.0
  Sr  Sr4  1  0.750  0.834  0.778  1.0
  Sr  Sr5  1  0.750  0.628  0.255  1.0
  W  W6  1  0.750  0.429  0.730  1.0
  W  W7  1  0.250  0.851  0.710  1.0
  W  W8  1  0.750  0.149  0.290  1.0
  W  W9  1  0.250  0.571  0.270  1.0
  O  O10  1  0.250  0.140  0.991  1.0
  O  O11  1  0.565  0.300  0.776  1.0
  O  O12  1  0.935  0.300  0.776  1.0
  O  O13  1  0.750  0.580  0.527  1.0
  O  O14  1  0.250  0.638  0.746  1.0
  O  O15  1  0.750  0.543  0.842  1.0
  O  O16  1  0.935  0.105  0.206  1.0
  O  O17  1  0.565  0.105  0.206  1.0
  O  O18  1  0.250  0.979  0.503  1.0
  O  O19  1  0.750  0.021  0.497  1.0
  O  O20  1  0.065  0.895  0.794  1.0
  O  O21  1  0.435  0.895  0.794  1.0
  O  O22  1  0.250  0.457  0.158  1.0
  O  O23  1  0.750  0.362  0.254  1.0
  O  O24  1  0.250  0.420  0.473  1.0
  O  O25  1  0.065  0.700  0.224  1.0
  O  O26  1  0.435  0.700  0.224  1.0
  O  O27  1  0.750  0.860  0.009  1.0
[/CIF]
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The compound described by Sr3W2O9 crystallizes in the monoclinic P2_1/m space group. There are three inequivalent Sr sites. In the first Sr site, Sr(1) is bonded to one O(1), one O(3), one O(4), and two equivalent O(2) atoms to form distorted SrO5 trigonal bipyramids that share  a cornercorner with one W(2)O4 tetrahedra, corners with three equivalent W(1)O4 tetrahedra,  a cornercorner with one Sr(3)O5 trigonal bipyramid, and edges with two equivalent Sr(2)O6 octahedra. In the second Sr site, Sr(2) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form SrO6 octahedra that share corners with two equivalent Sr(2)O6 octahedra, corners with two equivalent W(1)O4 tetrahedra, corners with two equivalent W(2)O4 tetrahedra, edges with two equivalent Sr(1)O5 trigonal bipyramids, and edges with two equivalent Sr(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 62°. In the third Sr site, Sr(3) is bonded to one O(1), one O(5), one O(7), and two equivalent O(6) atoms to form distorted SrO5 trigonal bipyramids that share  a cornercorner with one W(1)O4 tetrahedra, corners with three equivalent W(2)O4 tetrahedra,  a cornercorner with one Sr(1)O5 trigonal bipyramid, and edges with two equivalent Sr(2)O6 octahedra. There are two inequivalent W sites. In the first W site, W(1) is bonded to one O(3), one O(5), and two equivalent O(2) atoms to form WO4 tetrahedra that share corners with two equivalent Sr(2)O6 octahedra,  a cornercorner with one Sr(3)O5 trigonal bipyramid, and corners with three equivalent Sr(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 48°. In the second W site, W(2) is bonded to one O(4), one O(7), and two equivalent O(6) atoms to form WO4 tetrahedra that share corners with two equivalent Sr(2)O6 octahedra,  a cornercorner with one Sr(1)O5 trigonal bipyramid, and corners with three equivalent Sr(3)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 43°. There are seven inequivalent O sites. In the first O site, O(1) is bonded to one Sr(1), one Sr(3), and two equivalent Sr(2) atoms to form corner-sharing OSr4 tetrahedra. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Sr(1), one Sr(2), and one W(1) atom. In the third O site, O(3) is bonded in a bent 150 degrees geometry to one Sr(1) and one W(1) atom. In the fourth O site, O(4) is bonded in a linear geometry to one Sr(1) and one W(2) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Sr(3) and one W(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one Sr(2), one Sr(3), and one W(2) atom. In the seventh O site, O(7) is bonded in a linear geometry to one Sr(3) and one W(2) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3W2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.117
_cell_length_b   9.069
_cell_length_c   9.670
_cell_angle_alpha   62.850
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   633.416
_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
  Sr  Sr0  1  0.250  0.372  0.745  1.0
  Sr  Sr1  1  0.000  0.000  0.000  1.0
  Sr  Sr2  1  0.500  0.000  0.000  1.0
  Sr  Sr3  1  0.250  0.166  0.222  1.0
  Sr  Sr4  1  0.750  0.834  0.778  1.0
  Sr  Sr5  1  0.750  0.628  0.255  1.0
  W  W6  1  0.750  0.429  0.730  1.0
  W  W7  1  0.250  0.851  0.710  1.0
  W  W8  1  0.750  0.149  0.290  1.0
  W  W9  1  0.250  0.571  0.270  1.0
  O  O10  1  0.250  0.140  0.991  1.0
  O  O11  1  0.565  0.300  0.776  1.0
  O  O12  1  0.935  0.300  0.776  1.0
  O  O13  1  0.750  0.580  0.527  1.0
  O  O14  1  0.250  0.638  0.746  1.0
  O  O15  1  0.750  0.543  0.842  1.0
  O  O16  1  0.935  0.105  0.206  1.0
  O  O17  1  0.565  0.105  0.206  1.0
  O  O18  1  0.250  0.979  0.503  1.0
  O  O19  1  0.750  0.021  0.497  1.0
  O  O20  1  0.065  0.895  0.794  1.0
  O  O21  1  0.435  0.895  0.794  1.0
  O  O22  1  0.250  0.457  0.158  1.0
  O  O23  1  0.750  0.362  0.254  1.0
  O  O24  1  0.250  0.420  0.473  1.0
  O  O25  1  0.065  0.700  0.224  1.0
  O  O26  1  0.435  0.700  0.224  1.0
  O  O27  1  0.750  0.860  0.009  1.0
[/CIF]
.