The structure described by SrU3(SeO7)2(O2)2 crystallizes in the monoclinic C2 space group. The structure consists of four hydrogen peroxide molecules inside a SrU3(SeO7)2 framework. In the SrU3(SeO7)2 framework, Sr(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form distorted SrO6 pentagonal pyramids that share corners with four equivalent U(1)O7 pentagonal bipyramids. There are two inequivalent U sites. In the first U site, U(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form distorted UO7 pentagonal bipyramids that share corners with two equivalent Sr(1)O6 pentagonal pyramids and  an edgeedge with one U(1)O7 pentagonal bipyramid. In the second U site, U(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), two equivalent O(3), two equivalent O(6), and two equivalent O(7) atoms. Se(1) is bonded in a trigonal non-coplanar geometry to one O(6), one O(7), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one U(2) and two equivalent U(1) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one U(2) and two equivalent U(1) atoms. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Sr(1) and one U(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Sr(1) and one U(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Sr(1) and one U(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one U(1), one U(2), and one Se(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one U(1), one U(2), and one Se(1) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one U(1) and one Se(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrU3(SeO9)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.355
_cell_length_b   9.355
_cell_length_c   6.947
_cell_angle_alpha   81.680
_cell_angle_beta   81.680
_cell_angle_gamma   44.856
_symmetry_Int_Tables_number   1
_cell_volume   423.561
_cell_formula_units_Z   1
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  0.334  0.666  0.500  1.0
  U  U1  1  0.392  0.394  0.047  1.0
  U  U2  1  0.606  0.608  0.953  1.0
  U  U3  1  0.002  0.998  0.000  1.0
  Se  Se4  1  0.205  0.207  0.885  1.0
  Se  Se5  1  0.793  0.795  0.115  1.0
  O  O6  1  0.317  0.683  0.000  1.0
  O  O7  1  0.685  0.315  0.000  1.0
  O  O8  1  0.022  0.977  0.265  1.0
  O  O9  1  0.023  0.978  0.735  1.0
  O  O10  1  0.384  0.408  0.778  1.0
  O  O11  1  0.592  0.616  0.222  1.0
  O  O12  1  0.384  0.409  0.313  1.0
  O  O13  1  0.591  0.616  0.687  1.0
  O  O14  1  0.961  0.310  0.939  1.0
  O  O15  1  0.307  0.964  0.942  1.0
  O  O16  1  0.036  0.693  0.058  1.0
  O  O17  1  0.690  0.039  0.061  1.0
  O  O18  1  0.253  0.257  0.082  1.0
  O  O19  1  0.743  0.747  0.918  1.0
  O  O20  1  0.963  0.651  0.535  1.0
  O  O21  1  0.349  0.037  0.465  1.0
  O  O22  1  0.497  0.001  0.503  1.0
  O  O23  1  0.999  0.503  0.497  1.0
[/CIF]
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The structure described by SrU3(SeO7)2(O2)2 crystallizes in the monoclinic C2 space group. The structure consists of four hydrogen peroxide molecules inside a SrU3(SeO7)2 framework. In the SrU3(SeO7)2 framework, Sr(1) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form distorted SrO6 pentagonal pyramids that share corners with four equivalent U(1)O7 pentagonal bipyramids. There are two inequivalent U sites. In the first U site, U(1) is bonded to one O(1), one O(2), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form distorted UO7 pentagonal bipyramids that share corners with two equivalent Sr(1)O6 pentagonal pyramids and  an edgeedge with one U(1)O7 pentagonal bipyramid. In the second U site, U(2) is bonded in a 8-coordinate geometry to one O(1), one O(2), two equivalent O(3), two equivalent O(6), and two equivalent O(7) atoms. Se(1) is bonded in a trigonal non-coplanar geometry to one O(6), one O(7), and one O(8) atom. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one U(2) and two equivalent U(1) atoms. In the second O site, O(2) is bonded in a trigonal planar geometry to one U(2) and two equivalent U(1) atoms. In the third O site, O(3) is bonded in a distorted single-bond geometry to one Sr(1) and one U(2) atom. In the fourth O site, O(4) is bonded in a distorted single-bond geometry to one Sr(1) and one U(1) atom. In the fifth O site, O(5) is bonded in a distorted bent 120 degrees geometry to one Sr(1) and one U(1) atom. In the sixth O site, O(6) is bonded in a 3-coordinate geometry to one U(1), one U(2), and one Se(1) atom. In the seventh O site, O(7) is bonded in a 3-coordinate geometry to one U(1), one U(2), and one Se(1) atom. In the eighth O site, O(8) is bonded in a bent 120 degrees geometry to one U(1) and one Se(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrU3(SeO9)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   9.355
_cell_length_b   9.355
_cell_length_c   6.947
_cell_angle_alpha   81.680
_cell_angle_beta   81.680
_cell_angle_gamma   44.856
_symmetry_Int_Tables_number   1
_cell_volume   423.561
_cell_formula_units_Z   1
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  0.334  0.666  0.500  1.0
  U  U1  1  0.392  0.394  0.047  1.0
  U  U2  1  0.606  0.608  0.953  1.0
  U  U3  1  0.002  0.998  0.000  1.0
  Se  Se4  1  0.205  0.207  0.885  1.0
  Se  Se5  1  0.793  0.795  0.115  1.0
  O  O6  1  0.317  0.683  0.000  1.0
  O  O7  1  0.685  0.315  0.000  1.0
  O  O8  1  0.022  0.977  0.265  1.0
  O  O9  1  0.023  0.978  0.735  1.0
  O  O10  1  0.384  0.408  0.778  1.0
  O  O11  1  0.592  0.616  0.222  1.0
  O  O12  1  0.384  0.409  0.313  1.0
  O  O13  1  0.591  0.616  0.687  1.0
  O  O14  1  0.961  0.310  0.939  1.0
  O  O15  1  0.307  0.964  0.942  1.0
  O  O16  1  0.036  0.693  0.058  1.0
  O  O17  1  0.690  0.039  0.061  1.0
  O  O18  1  0.253  0.257  0.082  1.0
  O  O19  1  0.743  0.747  0.918  1.0
  O  O20  1  0.963  0.651  0.535  1.0
  O  O21  1  0.349  0.037  0.465  1.0
  O  O22  1  0.497  0.001  0.503  1.0
  O  O23  1  0.999  0.503  0.497  1.0
[/CIF]
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