The crystal structure described by SrFe2Se2O crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted water-like geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent O(2) atoms. In the second Sr site, Sr(2) is bonded in a distorted water-like geometry to one Se(3), one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent O(1) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted single-bond geometry to one Se(2), two equivalent Se(3), and one O(1) atom. In the second Fe site, Fe(2) is bonded to one Se(4), two equivalent Se(1), and one O(2) atom to form a mixture of distorted edge and corner-sharing FeSe3O tetrahedra. In the third Fe site, Fe(3) is bonded to one Se(1), two equivalent Se(4), and one O(1) atom to form a mixture of distorted edge and corner-sharing FeSe3O tetrahedra. In the fourth Fe site, Fe(4) is bonded to one Se(3), two equivalent Se(2), and one O(2) atom to form distorted corner-sharing FeSe3O tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Sr(1), two equivalent Sr(2), one Fe(3), and two equivalent Fe(2) atoms. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Sr(1), two equivalent Sr(2), one Fe(1), and two equivalent Fe(4) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Sr(2), two equivalent Sr(1), one Fe(4), and two equivalent Fe(1) atoms. In the fourth Se site, Se(4) is bonded in a 6-coordinate geometry to one Sr(2), two equivalent Sr(1), one Fe(2), and two equivalent Fe(3) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(2), one Fe(1), and one Fe(3) atom to form corner-sharing OSr2Fe2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Sr(1), one Fe(2), and one Fe(4) atom to form corner-sharing OSr2Fe2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrFe2Se2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.111
_cell_length_b   6.707
_cell_length_c   9.985
_cell_angle_alpha   90.092
_cell_angle_beta   89.741
_cell_angle_gamma   89.973
_symmetry_Int_Tables_number   1
_cell_volume   275.335
_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  0.499  0.998  0.501  1.0
  Sr  Sr1  1  1.000  0.001  0.000  1.0
  Fe  Fe2  1  0.501  0.373  0.836  1.0
  Fe  Fe3  1  0.999  0.629  0.335  1.0
  Fe  Fe4  1  0.505  0.369  0.165  1.0
  Fe  Fe5  1  0.005  0.628  0.663  1.0
  Se  Se6  1  0.499  0.748  0.198  1.0
  Se  Se7  1  0.500  0.749  0.800  1.0
  Se  Se8  1  0.001  0.252  0.700  1.0
  Se  Se9  1  0.998  0.252  0.302  1.0
  O  O10  1  0.497  0.219  1.000  1.0
  O  O11  1  0.997  0.782  0.500  1.0
[/CIF]
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The crystal structure described by SrFe2Se2O crystallizes in the triclinic P1 space group. There are two inequivalent Sr sites. In the first Sr site, Sr(1) is bonded in a distorted water-like geometry to one Se(1), one Se(2), two equivalent Se(3), two equivalent Se(4), and two equivalent O(2) atoms. In the second Sr site, Sr(2) is bonded in a distorted water-like geometry to one Se(3), one Se(4), two equivalent Se(1), two equivalent Se(2), and two equivalent O(1) atoms. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a distorted single-bond geometry to one Se(2), two equivalent Se(3), and one O(1) atom. In the second Fe site, Fe(2) is bonded to one Se(4), two equivalent Se(1), and one O(2) atom to form a mixture of distorted edge and corner-sharing FeSe3O tetrahedra. In the third Fe site, Fe(3) is bonded to one Se(1), two equivalent Se(4), and one O(1) atom to form a mixture of distorted edge and corner-sharing FeSe3O tetrahedra. In the fourth Fe site, Fe(4) is bonded to one Se(3), two equivalent Se(2), and one O(2) atom to form distorted corner-sharing FeSe3O tetrahedra. There are four inequivalent Se sites. In the first Se site, Se(1) is bonded in a 6-coordinate geometry to one Sr(1), two equivalent Sr(2), one Fe(3), and two equivalent Fe(2) atoms. In the second Se site, Se(2) is bonded in a 6-coordinate geometry to one Sr(1), two equivalent Sr(2), one Fe(1), and two equivalent Fe(4) atoms. In the third Se site, Se(3) is bonded in a 6-coordinate geometry to one Sr(2), two equivalent Sr(1), one Fe(4), and two equivalent Fe(1) atoms. In the fourth Se site, Se(4) is bonded in a 6-coordinate geometry to one Sr(2), two equivalent Sr(1), one Fe(2), and two equivalent Fe(3) atoms. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(2), one Fe(1), and one Fe(3) atom to form corner-sharing OSr2Fe2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Sr(1), one Fe(2), and one Fe(4) atom to form corner-sharing OSr2Fe2 tetrahedra. is represented by the Crystallographic Information File (CIF) [CIF]
data_SrFe2Se2O
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.111
_cell_length_b   6.707
_cell_length_c   9.985
_cell_angle_alpha   90.092
_cell_angle_beta   89.741
_cell_angle_gamma   89.973
_symmetry_Int_Tables_number   1
_cell_volume   275.335
_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  0.499  0.998  0.501  1.0
  Sr  Sr1  1  1.000  0.001  0.000  1.0
  Fe  Fe2  1  0.501  0.373  0.836  1.0
  Fe  Fe3  1  0.999  0.629  0.335  1.0
  Fe  Fe4  1  0.505  0.369  0.165  1.0
  Fe  Fe5  1  0.005  0.628  0.663  1.0
  Se  Se6  1  0.499  0.748  0.198  1.0
  Se  Se7  1  0.500  0.749  0.800  1.0
  Se  Se8  1  0.001  0.252  0.700  1.0
  Se  Se9  1  0.998  0.252  0.302  1.0
  O  O10  1  0.497  0.219  1.000  1.0
  O  O11  1  0.997  0.782  0.500  1.0
[/CIF]
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