The structure described by Ba2Fe2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded to four equivalent O(1) and eight equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, and faces with eight equivalent Fe(1)O5 square pyramids. Fe(1) is bonded to one O(1) and four equivalent O(2) atoms to form FeO5 square pyramids that share corners with five equivalent Fe(1)O5 square pyramids and faces with four equivalent Ba(2)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(2) and two equivalent Fe(1) atoms to form a mixture of distorted corner, edge, and face-sharing OBa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Fe(1) atoms to form a mixture of distorted corner, edge, and face-sharing OBa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Fe2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.976
_cell_length_b   3.977
_cell_length_c   8.157
_cell_angle_alpha   90.002
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   128.982
_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
  Ba  Ba0  1  0.000  0.000  0.000  1.0
  Ba  Ba1  1  0.000  0.000  0.500  1.0
  Fe  Fe2  1  0.500  0.500  0.269  1.0
  Fe  Fe3  1  0.500  0.500  0.731  1.0
  O  O4  1  0.500  0.500  0.500  1.0
  O  O5  1  0.500  1.000  0.231  1.0
  O  O6  1  0.500  0.000  0.769  1.0
  O  O7  1  0.000  0.500  0.231  1.0
  O  O8  1  0.000  0.500  0.769  1.0
[/CIF]
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The structure described by Ba2Fe2O5 crystallizes in the tetragonal P4/mmm space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a body-centered cubic geometry to eight equivalent O(2) atoms. In the second Ba site, Ba(2) is bonded to four equivalent O(1) and eight equivalent O(2) atoms to form BaO12 cuboctahedra that share corners with four equivalent Ba(2)O12 cuboctahedra, faces with four equivalent Ba(2)O12 cuboctahedra, and faces with eight equivalent Fe(1)O5 square pyramids. Fe(1) is bonded to one O(1) and four equivalent O(2) atoms to form FeO5 square pyramids that share corners with five equivalent Fe(1)O5 square pyramids and faces with four equivalent Ba(2)O12 cuboctahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Ba(2) and two equivalent Fe(1) atoms to form a mixture of distorted corner, edge, and face-sharing OBa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. In the second O site, O(2) is bonded to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Fe(1) atoms to form a mixture of distorted corner, edge, and face-sharing OBa4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-62°. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ba2Fe2O5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   3.976
_cell_length_b   3.977
_cell_length_c   8.157
_cell_angle_alpha   90.002
_cell_angle_beta   90.000
_cell_angle_gamma   90.000
_symmetry_Int_Tables_number   1
_cell_volume   128.982
_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
  Ba  Ba0  1  0.000  0.000  0.000  1.0
  Ba  Ba1  1  0.000  0.000  0.500  1.0
  Fe  Fe2  1  0.500  0.500  0.269  1.0
  Fe  Fe3  1  0.500  0.500  0.731  1.0
  O  O4  1  0.500  0.500  0.500  1.0
  O  O5  1  0.500  1.000  0.231  1.0
  O  O6  1  0.500  0.000  0.769  1.0
  O  O7  1  0.000  0.500  0.231  1.0
  O  O8  1  0.000  0.500  0.769  1.0
[/CIF]
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