The material described by SrO7I2 crystallizes in the monoclinic C2/c space group. Sr(1) is bonded in a 11-coordinate geometry to one O(4), two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Sr(1) and one I(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Sr(1) and one I(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Sr(1) and one I(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Sr(1) atom. I(1) is bonded in a 3-coordinate geometry to one O(1), one O(2), and one O(3) atom. is represented by the CIF file [CIF]
data_SrI2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.466
_cell_length_b   7.466
_cell_length_c   8.657
_cell_angle_alpha   57.164
_cell_angle_beta   57.164
_cell_angle_gamma   64.710
_symmetry_Int_Tables_number   1
_cell_volume   334.581
_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  0.842  0.158  0.750  1.0
  Sr  Sr1  1  0.158  0.842  0.250  1.0
  I  I2  1  0.716  0.653  0.295  1.0
  I  I3  1  0.347  0.284  0.205  1.0
  I  I4  1  0.284  0.347  0.705  1.0
  I  I5  1  0.653  0.716  0.795  1.0
  O  O6  1  0.797  0.918  0.126  1.0
  O  O7  1  0.082  0.203  0.374  1.0
  O  O8  1  0.203  0.082  0.874  1.0
  O  O9  1  0.918  0.797  0.626  1.0
  O  O10  1  0.783  0.597  0.493  1.0
  O  O11  1  0.403  0.217  0.007  1.0
  O  O12  1  0.217  0.403  0.507  1.0
  O  O13  1  0.597  0.783  0.993  1.0
  O  O14  1  0.420  0.742  0.406  1.0
  O  O15  1  0.258  0.580  0.094  1.0
  O  O16  1  0.580  0.258  0.594  1.0
  O  O17  1  0.742  0.420  0.906  1.0
  O  O18  1  0.170  0.830  0.750  1.0
  O  O19  1  0.830  0.170  0.250  1.0
[/CIF]
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The material described by SrO7I2 crystallizes in the monoclinic C2/c space group. Sr(1) is bonded in a 11-coordinate geometry to one O(4), two equivalent O(3), four equivalent O(1), and four equivalent O(2) atoms. There are four inequivalent O sites. In the first O site, O(1) is bonded in a 2-coordinate geometry to two equivalent Sr(1) and one I(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to two equivalent Sr(1) and one I(1) atom. In the third O site, O(3) is bonded in a distorted bent 120 degrees geometry to one Sr(1) and one I(1) atom. In the fourth O site, O(4) is bonded in a single-bond geometry to one Sr(1) atom. I(1) is bonded in a 3-coordinate geometry to one O(1), one O(2), and one O(3) atom. is represented by the CIF file [CIF]
data_SrI2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.466
_cell_length_b   7.466
_cell_length_c   8.657
_cell_angle_alpha   57.164
_cell_angle_beta   57.164
_cell_angle_gamma   64.710
_symmetry_Int_Tables_number   1
_cell_volume   334.581
_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  0.842  0.158  0.750  1.0
  Sr  Sr1  1  0.158  0.842  0.250  1.0
  I  I2  1  0.716  0.653  0.295  1.0
  I  I3  1  0.347  0.284  0.205  1.0
  I  I4  1  0.284  0.347  0.705  1.0
  I  I5  1  0.653  0.716  0.795  1.0
  O  O6  1  0.797  0.918  0.126  1.0
  O  O7  1  0.082  0.203  0.374  1.0
  O  O8  1  0.203  0.082  0.874  1.0
  O  O9  1  0.918  0.797  0.626  1.0
  O  O10  1  0.783  0.597  0.493  1.0
  O  O11  1  0.403  0.217  0.007  1.0
  O  O12  1  0.217  0.403  0.507  1.0
  O  O13  1  0.597  0.783  0.993  1.0
  O  O14  1  0.420  0.742  0.406  1.0
  O  O15  1  0.258  0.580  0.094  1.0
  O  O16  1  0.580  0.258  0.594  1.0
  O  O17  1  0.742  0.420  0.906  1.0
  O  O18  1  0.170  0.830  0.750  1.0
  O  O19  1  0.830  0.170  0.250  1.0
[/CIF]
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