The structure described by Sr2YTi2O7 crystallizes in the orthorhombic Ima2 space group. Sr(1) is bonded to two equivalent O(1) and four equivalent O(4) atoms to form distorted SrO6 pentagonal pyramids that share corners with six equivalent Sr(1)O6 pentagonal pyramids, corners with four equivalent Ti(1)O5 trigonal bipyramids, edges with three equivalent Sr(1)O6 pentagonal pyramids, and faces with two equivalent Sr(1)O6 pentagonal pyramids. Y(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. Ti(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted TiO5 trigonal bipyramids that share corners with four equivalent Sr(1)O6 pentagonal pyramids and corners with four equivalent Ti(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a square co-planar geometry to four equivalent Sr(1) atoms. In the second O site, O(2) is bonded to two equivalent Y(1) and two equivalent Ti(1) atoms to form a mixture of distorted corner and edge-sharing OY2Ti2 tetrahedra. In the third O site, O(3) is bonded to two equivalent Y(1) and two equivalent Ti(1) atoms to form a mixture of distorted corner and edge-sharing OY2Ti2 trigonal pyramids. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to four equivalent Sr(1) and one Ti(1) atom. is represented by the CIF file [CIF]
data_Sr2YTi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.363
_cell_length_b   13.363
_cell_length_c   13.363
_cell_angle_alpha   157.231
_cell_angle_beta   156.227
_cell_angle_gamma   33.152
_symmetry_Int_Tables_number   1
_cell_volume   371.902
_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  0.821  0.747  0.937  1.0
  Sr  Sr1  1  0.189  0.253  0.074  1.0
  Sr  Sr2  1  0.689  0.615  0.937  1.0
  Sr  Sr3  1  0.321  0.385  0.074  1.0
  Y  Y4  1  0.516  0.500  0.016  1.0
  Y  Y5  1  0.016  0.000  0.016  1.0
  Ti  Ti6  1  0.439  0.928  0.523  1.0
  Ti  Ti7  1  0.595  0.072  0.511  1.0
  Ti  Ti8  1  0.095  0.584  0.523  1.0
  Ti  Ti9  1  0.939  0.416  0.511  1.0
  O  O10  1  0.010  0.515  0.025  1.0
  O  O11  1  0.510  0.485  0.494  1.0
  O  O12  1  0.212  0.195  0.516  1.0
  O  O13  1  0.321  0.805  0.017  1.0
  O  O14  1  0.821  0.804  0.516  1.0
  O  O15  1  0.712  0.196  0.017  1.0
  O  O16  1  0.707  0.691  0.517  1.0
  O  O17  1  0.827  0.309  0.017  1.0
  O  O18  1  0.327  0.310  0.517  1.0
  O  O19  1  0.207  0.690  0.017  1.0
  O  O20  1  0.871  0.333  0.500  1.0
  O  O21  1  0.167  0.667  0.538  1.0
  O  O22  1  0.667  0.129  0.500  1.0
  O  O23  1  0.371  0.871  0.538  1.0
[/CIF]
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The structure described by Sr2YTi2O7 crystallizes in the orthorhombic Ima2 space group. Sr(1) is bonded to two equivalent O(1) and four equivalent O(4) atoms to form distorted SrO6 pentagonal pyramids that share corners with six equivalent Sr(1)O6 pentagonal pyramids, corners with four equivalent Ti(1)O5 trigonal bipyramids, edges with three equivalent Sr(1)O6 pentagonal pyramids, and faces with two equivalent Sr(1)O6 pentagonal pyramids. Y(1) is bonded in a body-centered cubic geometry to four equivalent O(2) and four equivalent O(3) atoms. Ti(1) is bonded to one O(4), two equivalent O(2), and two equivalent O(3) atoms to form distorted TiO5 trigonal bipyramids that share corners with four equivalent Sr(1)O6 pentagonal pyramids and corners with four equivalent Ti(1)O5 trigonal bipyramids. There are four inequivalent O sites. In the first O site, O(1) is bonded in a square co-planar geometry to four equivalent Sr(1) atoms. In the second O site, O(2) is bonded to two equivalent Y(1) and two equivalent Ti(1) atoms to form a mixture of distorted corner and edge-sharing OY2Ti2 tetrahedra. In the third O site, O(3) is bonded to two equivalent Y(1) and two equivalent Ti(1) atoms to form a mixture of distorted corner and edge-sharing OY2Ti2 trigonal pyramids. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to four equivalent Sr(1) and one Ti(1) atom. is represented by the CIF file [CIF]
data_Sr2YTi2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   13.363
_cell_length_b   13.363
_cell_length_c   13.363
_cell_angle_alpha   157.231
_cell_angle_beta   156.227
_cell_angle_gamma   33.152
_symmetry_Int_Tables_number   1
_cell_volume   371.902
_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  0.821  0.747  0.937  1.0
  Sr  Sr1  1  0.189  0.253  0.074  1.0
  Sr  Sr2  1  0.689  0.615  0.937  1.0
  Sr  Sr3  1  0.321  0.385  0.074  1.0
  Y  Y4  1  0.516  0.500  0.016  1.0
  Y  Y5  1  0.016  0.000  0.016  1.0
  Ti  Ti6  1  0.439  0.928  0.523  1.0
  Ti  Ti7  1  0.595  0.072  0.511  1.0
  Ti  Ti8  1  0.095  0.584  0.523  1.0
  Ti  Ti9  1  0.939  0.416  0.511  1.0
  O  O10  1  0.010  0.515  0.025  1.0
  O  O11  1  0.510  0.485  0.494  1.0
  O  O12  1  0.212  0.195  0.516  1.0
  O  O13  1  0.321  0.805  0.017  1.0
  O  O14  1  0.821  0.804  0.516  1.0
  O  O15  1  0.712  0.196  0.017  1.0
  O  O16  1  0.707  0.691  0.517  1.0
  O  O17  1  0.827  0.309  0.017  1.0
  O  O18  1  0.327  0.310  0.517  1.0
  O  O19  1  0.207  0.690  0.017  1.0
  O  O20  1  0.871  0.333  0.500  1.0
  O  O21  1  0.167  0.667  0.538  1.0
  O  O22  1  0.667  0.129  0.500  1.0
  O  O23  1  0.371  0.871  0.538  1.0
[/CIF]
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