The structure described by Sr2YAlSn2O7 crystallizes in the orthorhombic Ima2 space group. Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), two equivalent O(2), and three equivalent O(4) atoms. Y(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(3) atoms. Al(1) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form corner-sharing AlO4 tetrahedra. Sn(1) is bonded in a 4-coordinate geometry to one O(3), one O(4), and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(4) is bonded in a 5-coordinate geometry to three equivalent Sr(1), one Al(1), and one Sn(1) atom. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Sr(1) and two equivalent Al(1) atoms. In the third O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Sr(1), one Y(1), and two equivalent Sn(1) atoms. In the fourth O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Y(1), and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2YAlSn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.562
_cell_length_b   11.562
_cell_length_c   11.562
_cell_angle_alpha   150.479
_cell_angle_beta   145.055
_cell_angle_gamma   46.380
_symmetry_Int_Tables_number   1
_cell_volume   434.679
_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  0.766  0.833  0.922  1.0
  Sr  Sr1  1  0.234  0.156  0.067  1.0
  Sr  Sr2  1  0.589  0.656  0.922  1.0
  Sr  Sr3  1  0.411  0.333  0.067  1.0
  Y  Y4  1  0.500  0.443  0.943  1.0
  Y  Y5  1  0.000  0.943  0.943  1.0
  Al  Al6  1  0.143  0.761  0.404  1.0
  Al  Al7  1  0.857  0.261  0.618  1.0
  Sn  Sn8  1  0.924  0.397  0.479  1.0
  Sn  Sn9  1  0.076  0.555  0.473  1.0
  Sn  Sn10  1  0.582  0.055  0.479  1.0
  Sn  Sn11  1  0.418  0.897  0.473  1.0
  O  O12  1  0.939  0.561  1.000  1.0
  O  O13  1  0.061  0.061  0.623  1.0
  O  O14  1  0.701  0.757  0.601  1.0
  O  O15  1  0.299  0.900  0.056  1.0
  O  O16  1  0.344  0.400  0.601  1.0
  O  O17  1  0.656  0.257  0.056  1.0
  O  O18  1  0.034  0.064  0.254  1.0
  O  O19  1  0.966  0.220  0.030  1.0
  O  O20  1  0.690  0.720  0.254  1.0
  O  O21  1  0.310  0.564  0.030  1.0
  O  O22  1  0.367  0.782  0.517  1.0
  O  O23  1  0.633  0.150  0.415  1.0
  O  O24  1  0.235  0.650  0.517  1.0
  O  O25  1  0.765  0.282  0.415  1.0
[/CIF]
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The structure described by Sr2YAlSn2O7 crystallizes in the orthorhombic Ima2 space group. Sr(1) is bonded in a 7-coordinate geometry to one O(1), one O(3), two equivalent O(2), and three equivalent O(4) atoms. Y(1) is bonded in a 4-coordinate geometry to two equivalent O(2) and two equivalent O(3) atoms. Al(1) is bonded to two equivalent O(1) and two equivalent O(4) atoms to form corner-sharing AlO4 tetrahedra. Sn(1) is bonded in a 4-coordinate geometry to one O(3), one O(4), and two equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(4) is bonded in a 5-coordinate geometry to three equivalent Sr(1), one Al(1), and one Sn(1) atom. In the second O site, O(1) is bonded in a distorted bent 150 degrees geometry to two equivalent Sr(1) and two equivalent Al(1) atoms. In the third O site, O(2) is bonded in a 3-coordinate geometry to two equivalent Sr(1), one Y(1), and two equivalent Sn(1) atoms. In the fourth O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Sr(1), one Y(1), and one Sn(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Sr2YAlSn2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   11.562
_cell_length_b   11.562
_cell_length_c   11.562
_cell_angle_alpha   150.479
_cell_angle_beta   145.055
_cell_angle_gamma   46.380
_symmetry_Int_Tables_number   1
_cell_volume   434.679
_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  0.766  0.833  0.922  1.0
  Sr  Sr1  1  0.234  0.156  0.067  1.0
  Sr  Sr2  1  0.589  0.656  0.922  1.0
  Sr  Sr3  1  0.411  0.333  0.067  1.0
  Y  Y4  1  0.500  0.443  0.943  1.0
  Y  Y5  1  0.000  0.943  0.943  1.0
  Al  Al6  1  0.143  0.761  0.404  1.0
  Al  Al7  1  0.857  0.261  0.618  1.0
  Sn  Sn8  1  0.924  0.397  0.479  1.0
  Sn  Sn9  1  0.076  0.555  0.473  1.0
  Sn  Sn10  1  0.582  0.055  0.479  1.0
  Sn  Sn11  1  0.418  0.897  0.473  1.0
  O  O12  1  0.939  0.561  1.000  1.0
  O  O13  1  0.061  0.061  0.623  1.0
  O  O14  1  0.701  0.757  0.601  1.0
  O  O15  1  0.299  0.900  0.056  1.0
  O  O16  1  0.344  0.400  0.601  1.0
  O  O17  1  0.656  0.257  0.056  1.0
  O  O18  1  0.034  0.064  0.254  1.0
  O  O19  1  0.966  0.220  0.030  1.0
  O  O20  1  0.690  0.720  0.254  1.0
  O  O21  1  0.310  0.564  0.030  1.0
  O  O22  1  0.367  0.782  0.517  1.0
  O  O23  1  0.633  0.150  0.415  1.0
  O  O24  1  0.235  0.650  0.517  1.0
  O  O25  1  0.765  0.282  0.415  1.0
[/CIF]
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