The structure described by BaFe4O7 crystallizes in the hexagonal P6_3/m space group. Ba(1) is bonded in a distorted q6 geometry to three equivalent O(1) and six equivalent O(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1) and three equivalent O(2) atoms to form FeO4 tetrahedra that share corners with six equivalent Fe(2)O6 octahedra and  a cornercorner with one Fe(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-62°. In the second Fe site, Fe(2) is bonded to six equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra and edges with three equivalent Fe(2)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to three equivalent Ba(1) and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one Fe(1), and two equivalent Fe(2) atoms. is represented by the CIF file [CIF]
data_BaFe4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.117
_cell_length_b   5.117
_cell_length_c   13.937
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   316.014
_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
  Ba  Ba0  1  0.667  0.333  0.250  1.0
  Ba  Ba1  1  0.333  0.667  0.750  1.0
  Fe  Fe2  1  0.000  0.000  0.113  1.0
  Fe  Fe3  1  0.000  0.000  0.613  1.0
  Fe  Fe4  1  0.000  0.000  0.887  1.0
  Fe  Fe5  1  0.000  0.000  0.387  1.0
  Fe  Fe6  1  0.333  0.667  0.003  1.0
  Fe  Fe7  1  0.667  0.333  0.503  1.0
  Fe  Fe8  1  0.667  0.333  0.997  1.0
  Fe  Fe9  1  0.333  0.667  0.497  1.0
  O  O10  1  0.000  0.000  0.250  1.0
  O  O11  1  0.000  0.000  0.750  1.0
  O  O12  1  0.362  0.007  0.079  1.0
  O  O13  1  0.355  0.362  0.579  1.0
  O  O14  1  0.007  0.645  0.579  1.0
  O  O15  1  0.993  0.355  0.079  1.0
  O  O16  1  0.645  0.638  0.079  1.0
  O  O17  1  0.638  0.993  0.579  1.0
  O  O18  1  0.638  0.993  0.921  1.0
  O  O19  1  0.645  0.638  0.421  1.0
  O  O20  1  0.993  0.355  0.421  1.0
  O  O21  1  0.007  0.645  0.921  1.0
  O  O22  1  0.355  0.362  0.921  1.0
  O  O23  1  0.362  0.007  0.421  1.0
[/CIF]
.
The structure described by BaFe4O7 crystallizes in the hexagonal P6_3/m space group. Ba(1) is bonded in a distorted q6 geometry to three equivalent O(1) and six equivalent O(2) atoms. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1) and three equivalent O(2) atoms to form FeO4 tetrahedra that share corners with six equivalent Fe(2)O6 octahedra and  a cornercorner with one Fe(1)O4 tetrahedra. The corner-sharing octahedral tilt angles range from 59-62°. In the second Fe site, Fe(2) is bonded to six equivalent O(2) atoms to form FeO6 octahedra that share corners with six equivalent Fe(1)O4 tetrahedra and edges with three equivalent Fe(2)O6 octahedra. There are two inequivalent O sites. In the first O site, O(1) is bonded in a distorted linear geometry to three equivalent Ba(1) and two equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a 3-coordinate geometry to one Ba(1), one Fe(1), and two equivalent Fe(2) atoms. is represented by the CIF file [CIF]
data_BaFe4O7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.117
_cell_length_b   5.117
_cell_length_c   13.937
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   120.000
_symmetry_Int_Tables_number   1
_cell_volume   316.014
_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
  Ba  Ba0  1  0.667  0.333  0.250  1.0
  Ba  Ba1  1  0.333  0.667  0.750  1.0
  Fe  Fe2  1  0.000  0.000  0.113  1.0
  Fe  Fe3  1  0.000  0.000  0.613  1.0
  Fe  Fe4  1  0.000  0.000  0.887  1.0
  Fe  Fe5  1  0.000  0.000  0.387  1.0
  Fe  Fe6  1  0.333  0.667  0.003  1.0
  Fe  Fe7  1  0.667  0.333  0.503  1.0
  Fe  Fe8  1  0.667  0.333  0.997  1.0
  Fe  Fe9  1  0.333  0.667  0.497  1.0
  O  O10  1  0.000  0.000  0.250  1.0
  O  O11  1  0.000  0.000  0.750  1.0
  O  O12  1  0.362  0.007  0.079  1.0
  O  O13  1  0.355  0.362  0.579  1.0
  O  O14  1  0.007  0.645  0.579  1.0
  O  O15  1  0.993  0.355  0.079  1.0
  O  O16  1  0.645  0.638  0.079  1.0
  O  O17  1  0.638  0.993  0.579  1.0
  O  O18  1  0.638  0.993  0.921  1.0
  O  O19  1  0.645  0.638  0.421  1.0
  O  O20  1  0.993  0.355  0.421  1.0
  O  O21  1  0.007  0.645  0.921  1.0
  O  O22  1  0.355  0.362  0.921  1.0
  O  O23  1  0.362  0.007  0.421  1.0
[/CIF]
.