The structure described by Sr3W2O9 crystallizes in the trigonal R-3c space group. Sr(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with six equivalent Sr(1)O12 cuboctahedra, corners with four equivalent W(1)O6 octahedra, faces with eight equivalent Sr(1)O12 cuboctahedra, and faces with four equivalent W(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-30°. W(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted WO6 octahedra that share corners with six equivalent Sr(1)O12 cuboctahedra, faces with six equivalent Sr(1)O12 cuboctahedra, and  a faceface with one W(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(2) is bonded to four equivalent Sr(1) and two equivalent W(1) atoms to form a mixture of distorted edge, corner, and face-sharing OSr4W2 octahedra. The corner-sharing octahedral tilt angles range from 38-58°. In the second O site, O(1) is bonded in a distorted single-bond geometry to four equivalent Sr(1) and one W(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3W2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.348
_cell_length_b   7.348
_cell_length_c   7.348
_cell_angle_alpha   84.888
_cell_angle_beta   84.888
_cell_angle_gamma   84.888
_symmetry_Int_Tables_number   1
_cell_volume   392.244
_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  0.923  0.250  0.577  1.0
  Sr  Sr1  1  0.423  0.077  0.750  1.0
  Sr  Sr2  1  0.750  0.423  0.077  1.0
  Sr  Sr3  1  0.250  0.577  0.923  1.0
  Sr  Sr4  1  0.577  0.923  0.250  1.0
  Sr  Sr5  1  0.077  0.750  0.423  1.0
  W  W6  1  0.857  0.857  0.857  1.0
  W  W7  1  0.357  0.357  0.357  1.0
  W  W8  1  0.143  0.143  0.143  1.0
  W  W9  1  0.643  0.643  0.643  1.0
  O  O10  1  0.920  0.084  0.257  1.0
  O  O11  1  0.743  0.080  0.916  1.0
  O  O12  1  0.901  0.599  0.750  1.0
  O  O13  1  0.580  0.243  0.416  1.0
  O  O14  1  0.250  0.099  0.401  1.0
  O  O15  1  0.401  0.250  0.099  1.0
  O  O16  1  0.584  0.420  0.757  1.0
  O  O17  1  0.757  0.584  0.420  1.0
  O  O18  1  0.916  0.743  0.080  1.0
  O  O19  1  0.084  0.257  0.920  1.0
  O  O20  1  0.243  0.416  0.580  1.0
  O  O21  1  0.750  0.901  0.599  1.0
  O  O22  1  0.416  0.580  0.243  1.0
  O  O23  1  0.599  0.750  0.901  1.0
  O  O24  1  0.420  0.757  0.584  1.0
  O  O25  1  0.099  0.401  0.250  1.0
  O  O26  1  0.257  0.920  0.084  1.0
  O  O27  1  0.080  0.916  0.743  1.0
[/CIF]
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The structure described by Sr3W2O9 crystallizes in the trigonal R-3c space group. Sr(1) is bonded to four equivalent O(2) and eight equivalent O(1) atoms to form SrO12 cuboctahedra that share corners with six equivalent Sr(1)O12 cuboctahedra, corners with four equivalent W(1)O6 octahedra, faces with eight equivalent Sr(1)O12 cuboctahedra, and faces with four equivalent W(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 7-30°. W(1) is bonded to three equivalent O(1) and three equivalent O(2) atoms to form distorted WO6 octahedra that share corners with six equivalent Sr(1)O12 cuboctahedra, faces with six equivalent Sr(1)O12 cuboctahedra, and  a faceface with one W(1)O6 octahedra. There are two inequivalent O sites. In the first O site, O(2) is bonded to four equivalent Sr(1) and two equivalent W(1) atoms to form a mixture of distorted edge, corner, and face-sharing OSr4W2 octahedra. The corner-sharing octahedral tilt angles range from 38-58°. In the second O site, O(1) is bonded in a distorted single-bond geometry to four equivalent Sr(1) and one W(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr3W2O9
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.348
_cell_length_b   7.348
_cell_length_c   7.348
_cell_angle_alpha   84.888
_cell_angle_beta   84.888
_cell_angle_gamma   84.888
_symmetry_Int_Tables_number   1
_cell_volume   392.244
_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  0.923  0.250  0.577  1.0
  Sr  Sr1  1  0.423  0.077  0.750  1.0
  Sr  Sr2  1  0.750  0.423  0.077  1.0
  Sr  Sr3  1  0.250  0.577  0.923  1.0
  Sr  Sr4  1  0.577  0.923  0.250  1.0
  Sr  Sr5  1  0.077  0.750  0.423  1.0
  W  W6  1  0.857  0.857  0.857  1.0
  W  W7  1  0.357  0.357  0.357  1.0
  W  W8  1  0.143  0.143  0.143  1.0
  W  W9  1  0.643  0.643  0.643  1.0
  O  O10  1  0.920  0.084  0.257  1.0
  O  O11  1  0.743  0.080  0.916  1.0
  O  O12  1  0.901  0.599  0.750  1.0
  O  O13  1  0.580  0.243  0.416  1.0
  O  O14  1  0.250  0.099  0.401  1.0
  O  O15  1  0.401  0.250  0.099  1.0
  O  O16  1  0.584  0.420  0.757  1.0
  O  O17  1  0.757  0.584  0.420  1.0
  O  O18  1  0.916  0.743  0.080  1.0
  O  O19  1  0.084  0.257  0.920  1.0
  O  O20  1  0.243  0.416  0.580  1.0
  O  O21  1  0.750  0.901  0.599  1.0
  O  O22  1  0.416  0.580  0.243  1.0
  O  O23  1  0.599  0.750  0.901  1.0
  O  O24  1  0.420  0.757  0.584  1.0
  O  O25  1  0.099  0.401  0.250  1.0
  O  O26  1  0.257  0.920  0.084  1.0
  O  O27  1  0.080  0.916  0.743  1.0
[/CIF]
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