The material structure described by Sr3Ir2O7 crystallizes in the orthorhombic Ccce space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to four equivalent O(2) and four equivalent O(3) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to two equivalent O(2) and five equivalent O(1) atoms. Ir(1) is bonded to one O(1), one O(3), and four equivalent O(2) atoms to form corner-sharing IrO6 octahedra. The corner-sharing octahedral tilt angles range from 0-27°. There are three inequivalent O sites. In the first O site, O(1) is bonded to five equivalent Sr(2) and one Ir(1) atom to form OSr5Ir octahedra that share  a cornercorner with one O(3)Sr4Ir2 octahedra, corners with four equivalent O(1)Sr5Ir octahedra, and edges with eight equivalent O(1)Sr5Ir octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), and two equivalent Ir(1) atoms. In the third O site, O(3) is bonded to four equivalent Sr(1) and two equivalent Ir(1) atoms to form OSr4Ir2 octahedra that share corners with two equivalent O(1)Sr5Ir octahedra, corners with four equivalent O(3)Sr4Ir2 octahedra, and edges with four equivalent O(3)Sr4Ir2 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_Sr3Ir2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.859
_cell_length_b   10.859
_cell_length_c   5.531
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   150.484
_symmetry_Int_Tables_number   1
_cell_volume   321.343
_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  0.500  0.500  0.000  1.0
  Sr  Sr1  1  0.313  0.687  0.000  1.0
  Sr  Sr2  1  0.687  0.313  0.000  1.0
  Sr  Sr3  1  0.187  0.813  0.500  1.0
  Sr  Sr4  1  0.813  0.187  0.500  1.0
  Sr  Sr5  1  0.000  0.000  0.500  1.0
  Ir  Ir6  1  0.097  0.903  0.000  1.0
  Ir  Ir7  1  0.903  0.097  0.000  1.0
  Ir  Ir8  1  0.403  0.597  0.500  1.0
  Ir  Ir9  1  0.597  0.403  0.500  1.0
  O  O10  1  0.194  0.806  0.000  1.0
  O  O11  1  0.093  0.286  0.690  1.0
  O  O12  1  0.593  0.786  0.810  1.0
  O  O13  1  0.000  0.000  0.000  1.0
  O  O14  1  0.806  0.194  0.000  1.0
  O  O15  1  0.407  0.214  0.810  1.0
  O  O16  1  0.306  0.694  0.500  1.0
  O  O17  1  0.500  0.500  0.500  1.0
  O  O18  1  0.214  0.407  0.190  1.0
  O  O19  1  0.286  0.093  0.310  1.0
  O  O20  1  0.694  0.306  0.500  1.0
  O  O21  1  0.714  0.907  0.310  1.0
  O  O22  1  0.907  0.714  0.690  1.0
  O  O23  1  0.786  0.593  0.190  1.0
[/CIF]
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The material structure described by Sr3Ir2O7 crystallizes in the orthorhombic Ccce space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a 8-coordinate geometry to four equivalent O(2) and four equivalent O(3) atoms. In the second Sr site, Sr(2) is bonded in a 7-coordinate geometry to two equivalent O(2) and five equivalent O(1) atoms. Ir(1) is bonded to one O(1), one O(3), and four equivalent O(2) atoms to form corner-sharing IrO6 octahedra. The corner-sharing octahedral tilt angles range from 0-27°. There are three inequivalent O sites. In the first O site, O(1) is bonded to five equivalent Sr(2) and one Ir(1) atom to form OSr5Ir octahedra that share  a cornercorner with one O(3)Sr4Ir2 octahedra, corners with four equivalent O(1)Sr5Ir octahedra, and edges with eight equivalent O(1)Sr5Ir octahedra. The corner-sharing octahedral tilt angles range from 0-6°. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Sr(1), one Sr(2), and two equivalent Ir(1) atoms. In the third O site, O(3) is bonded to four equivalent Sr(1) and two equivalent Ir(1) atoms to form OSr4Ir2 octahedra that share corners with two equivalent O(1)Sr5Ir octahedra, corners with four equivalent O(3)Sr4Ir2 octahedra, and edges with four equivalent O(3)Sr4Ir2 octahedra. The corner-sharing octahedra are not tilted. is represented by the CIF card [CIF]
data_Sr3Ir2O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   10.859
_cell_length_b   10.859
_cell_length_c   5.531
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   150.484
_symmetry_Int_Tables_number   1
_cell_volume   321.343
_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  0.500  0.500  0.000  1.0
  Sr  Sr1  1  0.313  0.687  0.000  1.0
  Sr  Sr2  1  0.687  0.313  0.000  1.0
  Sr  Sr3  1  0.187  0.813  0.500  1.0
  Sr  Sr4  1  0.813  0.187  0.500  1.0
  Sr  Sr5  1  0.000  0.000  0.500  1.0
  Ir  Ir6  1  0.097  0.903  0.000  1.0
  Ir  Ir7  1  0.903  0.097  0.000  1.0
  Ir  Ir8  1  0.403  0.597  0.500  1.0
  Ir  Ir9  1  0.597  0.403  0.500  1.0
  O  O10  1  0.194  0.806  0.000  1.0
  O  O11  1  0.093  0.286  0.690  1.0
  O  O12  1  0.593  0.786  0.810  1.0
  O  O13  1  0.000  0.000  0.000  1.0
  O  O14  1  0.806  0.194  0.000  1.0
  O  O15  1  0.407  0.214  0.810  1.0
  O  O16  1  0.306  0.694  0.500  1.0
  O  O17  1  0.500  0.500  0.500  1.0
  O  O18  1  0.214  0.407  0.190  1.0
  O  O19  1  0.286  0.093  0.310  1.0
  O  O20  1  0.694  0.306  0.500  1.0
  O  O21  1  0.714  0.907  0.310  1.0
  O  O22  1  0.907  0.714  0.690  1.0
  O  O23  1  0.786  0.593  0.190  1.0
[/CIF]
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