The structure described by Sr2Y2W2O7 crystallizes in the orthorhombic Ima2 space group. Sr(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), and two equivalent O(4) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(3) atoms. In the second Y site, Y(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form YO4 tetrahedra that share corners with two equivalent W(1)O5 square pyramids and corners with two equivalent Y(2)O4 tetrahedra. W(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form WO5 square pyramids that share corners with four equivalent W(1)O5 square pyramids and  a cornercorner with one Y(2)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Y(2), and one W(1) atom. In the second O site, O(1) is bonded to two equivalent Sr(1) and two equivalent Y(2) atoms to form corner-sharing OSr2Y2 tetrahedra. In the third O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Y(1), and two equivalent W(1) atoms. In the fourth O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Y(1), and two equivalent W(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2Y2W2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.639
_cell_length_b   12.639
_cell_length_c   12.639
_cell_angle_alpha   153.188
_cell_angle_beta   152.372
_cell_angle_gamma   38.879
_symmetry_Int_Tables_number   1
_cell_volume   421.561
_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  0.807  0.856  0.963  1.0
  Sr  Sr1  1  0.193  0.156  0.050  1.0
  Sr  Sr2  1  0.606  0.656  0.963  1.0
  Sr  Sr3  1  0.394  0.356  0.050  1.0
  Y  Y4  1  0.500  0.463  0.963  1.0
  Y  Y5  1  0.000  0.963  0.963  1.0
  Y  Y6  1  0.184  0.781  0.466  1.0
  Y  Y7  1  0.816  0.281  0.597  1.0
  W  W8  1  0.934  0.399  0.469  1.0
  W  W9  1  0.066  0.535  0.465  1.0
  W  W10  1  0.570  0.035  0.469  1.0
  W  W11  1  0.430  0.899  0.465  1.0
  O  O12  1  0.846  0.655  0.001  1.0
  O  O13  1  0.154  0.155  0.809  1.0
  O  O14  1  0.742  0.711  0.594  1.0
  O  O15  1  0.258  0.852  0.970  1.0
  O  O16  1  0.382  0.352  0.594  1.0
  O  O17  1  0.618  0.211  0.970  1.0
  O  O18  1  0.111  0.074  0.327  1.0
  O  O19  1  0.889  0.217  0.964  1.0
  O  O20  1  0.753  0.717  0.327  1.0
  O  O21  1  0.247  0.574  0.964  1.0
  O  O22  1  0.382  0.772  0.490  1.0
  O  O23  1  0.618  0.108  0.390  1.0
  O  O24  1  0.218  0.608  0.490  1.0
  O  O25  1  0.782  0.272  0.390  1.0
[/CIF]
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The structure described by Sr2Y2W2O7 crystallizes in the orthorhombic Ima2 space group. Sr(1) is bonded in a 5-coordinate geometry to one O(1), one O(2), one O(3), and two equivalent O(4) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(3) atoms. In the second Y site, Y(2) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form YO4 tetrahedra that share corners with two equivalent W(1)O5 square pyramids and corners with two equivalent Y(2)O4 tetrahedra. W(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form WO5 square pyramids that share corners with four equivalent W(1)O5 square pyramids and  a cornercorner with one Y(2)O4 tetrahedra. There are four inequivalent O sites. In the first O site, O(4) is bonded in a 4-coordinate geometry to two equivalent Sr(1), one Y(2), and one W(1) atom. In the second O site, O(1) is bonded to two equivalent Sr(1) and two equivalent Y(2) atoms to form corner-sharing OSr2Y2 tetrahedra. In the third O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Y(1), and two equivalent W(1) atoms. In the fourth O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Sr(1), one Y(1), and two equivalent W(1) atoms. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2Y2W2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   12.639
_cell_length_b   12.639
_cell_length_c   12.639
_cell_angle_alpha   153.188
_cell_angle_beta   152.372
_cell_angle_gamma   38.879
_symmetry_Int_Tables_number   1
_cell_volume   421.561
_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  0.807  0.856  0.963  1.0
  Sr  Sr1  1  0.193  0.156  0.050  1.0
  Sr  Sr2  1  0.606  0.656  0.963  1.0
  Sr  Sr3  1  0.394  0.356  0.050  1.0
  Y  Y4  1  0.500  0.463  0.963  1.0
  Y  Y5  1  0.000  0.963  0.963  1.0
  Y  Y6  1  0.184  0.781  0.466  1.0
  Y  Y7  1  0.816  0.281  0.597  1.0
  W  W8  1  0.934  0.399  0.469  1.0
  W  W9  1  0.066  0.535  0.465  1.0
  W  W10  1  0.570  0.035  0.469  1.0
  W  W11  1  0.430  0.899  0.465  1.0
  O  O12  1  0.846  0.655  0.001  1.0
  O  O13  1  0.154  0.155  0.809  1.0
  O  O14  1  0.742  0.711  0.594  1.0
  O  O15  1  0.258  0.852  0.970  1.0
  O  O16  1  0.382  0.352  0.594  1.0
  O  O17  1  0.618  0.211  0.970  1.0
  O  O18  1  0.111  0.074  0.327  1.0
  O  O19  1  0.889  0.217  0.964  1.0
  O  O20  1  0.753  0.717  0.327  1.0
  O  O21  1  0.247  0.574  0.964  1.0
  O  O22  1  0.382  0.772  0.490  1.0
  O  O23  1  0.618  0.108  0.390  1.0
  O  O24  1  0.218  0.608  0.490  1.0
  O  O25  1  0.782  0.272  0.390  1.0
[/CIF]
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