The material described by Bi7Fe3Ti3O21 crystallizes in the monoclinic Cm space group. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(3), one O(7), and four equivalent O(9) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and corners with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-19°. In the second Ti site, Ti(2) is bonded to one O(13), one O(2), and four equivalent O(4) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra and corners with four equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-21°. In the third Ti site, Ti(3) is bonded to one O(1), one O(14), and four equivalent O(5) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Fe(3)O6 octahedra and corners with four equivalent Ti(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-21°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(6), and four equivalent O(8) atoms to form FeO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-19°. In the second Fe site, Fe(2) is bonded to one O(13), one O(6), and four equivalent O(11) atoms to form FeO6 octahedra that share  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and corners with four equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-16°. In the third Fe site, Fe(3) is bonded to one O(14), one O(7), and four equivalent O(12) atoms to form FeO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra, and corners with four equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-19°. There are seven inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 3-coordinate geometry to one O(14), two equivalent O(12), and two equivalent O(5) atoms. In the second Bi site, Bi(2) is bonded in a 3-coordinate geometry to one O(13) and two equivalent O(4) atoms. In the third Bi site, Bi(3) is bonded in a 3-coordinate geometry to one O(3), two equivalent O(8), and two equivalent O(9) atoms. In the fourth Bi site, Bi(4) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(12), and two equivalent O(9) atoms. In the fifth Bi site, Bi(5) is bonded in a 3-coordinate geometry to one O(6) and two equivalent O(11) atoms. In the sixth Bi site, Bi(6) is bonded in a distorted pentagonal planar geometry to one O(1) and four equivalent O(10) atoms. In the seventh Bi site, Bi(7) is bonded in a distorted pentagonal planar geometry to one O(2) and four equivalent O(10) atoms. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ti(3) and one Bi(6) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ti(2) and one Bi(7) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ti(1), one Fe(1), and one Bi(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ti(2) and one Bi(2) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to two equivalent Ti(3) and one Bi(1) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(2), and one Bi(5) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Ti(1), one Fe(3), and one Bi(4) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Bi(3) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to two equivalent Ti(1), one Bi(3), and one Bi(4) atom. In the tenth O site, O(10) is bonded to two equivalent Bi(6) and two equivalent Bi(7) atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to two equivalent Fe(2) and one Bi(5) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to two equivalent Fe(3), one Bi(1), and one Bi(4) atom. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Ti(2), one Fe(2), and one Bi(2) atom. In the fourteenth O site, O(14) is bonded in a distorted T-shaped geometry to one Ti(3), one Fe(3), and one Bi(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ti3Fe3(BiO3)7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.041
_cell_length_b   4.041
_cell_length_c   28.399
_cell_angle_alpha   85.806
_cell_angle_beta   86.319
_cell_angle_gamma   91.987
_symmetry_Int_Tables_number   1
_cell_volume   461.083
_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
  Ti  Ti0  1  0.432  0.496  0.072  1.0
  Ti  Ti1  1  0.671  0.688  0.641  1.0
  Ti  Ti2  1  0.310  0.332  0.358  1.0
  Fe  Fe3  1  0.488  0.581  0.930  1.0
  Fe  Fe4  1  0.576  0.638  0.786  1.0
  Fe  Fe5  1  0.357  0.431  0.213  1.0
  Bi  Bi6  1  0.907  0.804  0.290  1.0
  Bi  Bi7  1  0.202  0.090  0.708  1.0
  Bi  Bi8  1  0.028  0.979  0.994  1.0
  Bi  Bi9  1  0.957  0.895  0.148  1.0
  Bi  Bi10  1  0.117  0.034  0.850  1.0
  Bi  Bi11  1  0.860  0.686  0.455  1.0
  Bi  Bi12  1  0.312  0.145  0.543  1.0
  O  O13  1  0.240  0.340  0.421  1.0
  O  O14  1  0.662  0.759  0.579  1.0
  O  O15  1  0.401  0.596  0.003  1.0
  O  O16  1  0.616  0.217  0.652  1.0
  O  O17  1  0.778  0.391  0.348  1.0
  O  O18  1  0.132  0.732  0.652  1.0
  O  O19  1  0.261  0.874  0.348  1.0
  O  O20  1  0.486  0.654  0.860  1.0
  O  O21  1  0.337  0.523  0.140  1.0
  O  O22  1  0.965  0.632  0.935  1.0
  O  O23  1  0.367  0.045  0.072  1.0
  O  O24  1  0.432  0.100  0.935  1.0
  O  O25  1  0.882  0.561  0.072  1.0
  O  O26  1  0.278  0.721  0.499  1.0
  O  O27  1  0.780  0.222  0.499  1.0
  O  O28  1  0.518  0.157  0.791  1.0
  O  O29  1  0.837  0.490  0.208  1.0
  O  O30  1  0.052  0.691  0.791  1.0
  O  O31  1  0.302  0.955  0.208  1.0
  O  O32  1  0.572  0.711  0.717  1.0
  O  O33  1  0.284  0.433  0.282  1.0
[/CIF]
.
The material described by Bi7Fe3Ti3O21 crystallizes in the monoclinic Cm space group. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(3), one O(7), and four equivalent O(9) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, and corners with four equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-19°. In the second Ti site, Ti(2) is bonded to one O(13), one O(2), and four equivalent O(4) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra and corners with four equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-21°. In the third Ti site, Ti(3) is bonded to one O(1), one O(14), and four equivalent O(5) atoms to form distorted TiO6 octahedra that share  a cornercorner with one Fe(3)O6 octahedra and corners with four equivalent Ti(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 16-21°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), one O(6), and four equivalent O(8) atoms to form FeO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra, and corners with four equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-19°. In the second Fe site, Fe(2) is bonded to one O(13), one O(6), and four equivalent O(11) atoms to form FeO6 octahedra that share  a cornercorner with one Ti(2)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, and corners with four equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-16°. In the third Fe site, Fe(3) is bonded to one O(14), one O(7), and four equivalent O(12) atoms to form FeO6 octahedra that share  a cornercorner with one Ti(1)O6 octahedra,  a cornercorner with one Ti(3)O6 octahedra, and corners with four equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 15-19°. There are seven inequivalent Bi sites. In the first Bi site, Bi(1) is bonded in a 3-coordinate geometry to one O(14), two equivalent O(12), and two equivalent O(5) atoms. In the second Bi site, Bi(2) is bonded in a 3-coordinate geometry to one O(13) and two equivalent O(4) atoms. In the third Bi site, Bi(3) is bonded in a 3-coordinate geometry to one O(3), two equivalent O(8), and two equivalent O(9) atoms. In the fourth Bi site, Bi(4) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(12), and two equivalent O(9) atoms. In the fifth Bi site, Bi(5) is bonded in a 3-coordinate geometry to one O(6) and two equivalent O(11) atoms. In the sixth Bi site, Bi(6) is bonded in a distorted pentagonal planar geometry to one O(1) and four equivalent O(10) atoms. In the seventh Bi site, Bi(7) is bonded in a distorted pentagonal planar geometry to one O(2) and four equivalent O(10) atoms. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a distorted bent 120 degrees geometry to one Ti(3) and one Bi(6) atom. In the second O site, O(2) is bonded in a distorted bent 120 degrees geometry to one Ti(2) and one Bi(7) atom. In the third O site, O(3) is bonded in a distorted T-shaped geometry to one Ti(1), one Fe(1), and one Bi(3) atom. In the fourth O site, O(4) is bonded in a 3-coordinate geometry to two equivalent Ti(2) and one Bi(2) atom. In the fifth O site, O(5) is bonded in a distorted T-shaped geometry to two equivalent Ti(3) and one Bi(1) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(2), and one Bi(5) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Ti(1), one Fe(3), and one Bi(4) atom. In the eighth O site, O(8) is bonded in a 3-coordinate geometry to two equivalent Fe(1) and one Bi(3) atom. In the ninth O site, O(9) is bonded in a 4-coordinate geometry to two equivalent Ti(1), one Bi(3), and one Bi(4) atom. In the tenth O site, O(10) is bonded to two equivalent Bi(6) and two equivalent Bi(7) atoms to form a mixture of distorted edge and corner-sharing OBi4 tetrahedra. In the eleventh O site, O(11) is bonded in a 3-coordinate geometry to two equivalent Fe(2) and one Bi(5) atom. In the twelfth O site, O(12) is bonded in a 4-coordinate geometry to two equivalent Fe(3), one Bi(1), and one Bi(4) atom. In the thirteenth O site, O(13) is bonded in a distorted T-shaped geometry to one Ti(2), one Fe(2), and one Bi(2) atom. In the fourteenth O site, O(14) is bonded in a distorted T-shaped geometry to one Ti(3), one Fe(3), and one Bi(1) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_Ti3Fe3(BiO3)7
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   4.041
_cell_length_b   4.041
_cell_length_c   28.399
_cell_angle_alpha   85.806
_cell_angle_beta   86.319
_cell_angle_gamma   91.987
_symmetry_Int_Tables_number   1
_cell_volume   461.083
_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
  Ti  Ti0  1  0.432  0.496  0.072  1.0
  Ti  Ti1  1  0.671  0.688  0.641  1.0
  Ti  Ti2  1  0.310  0.332  0.358  1.0
  Fe  Fe3  1  0.488  0.581  0.930  1.0
  Fe  Fe4  1  0.576  0.638  0.786  1.0
  Fe  Fe5  1  0.357  0.431  0.213  1.0
  Bi  Bi6  1  0.907  0.804  0.290  1.0
  Bi  Bi7  1  0.202  0.090  0.708  1.0
  Bi  Bi8  1  0.028  0.979  0.994  1.0
  Bi  Bi9  1  0.957  0.895  0.148  1.0
  Bi  Bi10  1  0.117  0.034  0.850  1.0
  Bi  Bi11  1  0.860  0.686  0.455  1.0
  Bi  Bi12  1  0.312  0.145  0.543  1.0
  O  O13  1  0.240  0.340  0.421  1.0
  O  O14  1  0.662  0.759  0.579  1.0
  O  O15  1  0.401  0.596  0.003  1.0
  O  O16  1  0.616  0.217  0.652  1.0
  O  O17  1  0.778  0.391  0.348  1.0
  O  O18  1  0.132  0.732  0.652  1.0
  O  O19  1  0.261  0.874  0.348  1.0
  O  O20  1  0.486  0.654  0.860  1.0
  O  O21  1  0.337  0.523  0.140  1.0
  O  O22  1  0.965  0.632  0.935  1.0
  O  O23  1  0.367  0.045  0.072  1.0
  O  O24  1  0.432  0.100  0.935  1.0
  O  O25  1  0.882  0.561  0.072  1.0
  O  O26  1  0.278  0.721  0.499  1.0
  O  O27  1  0.780  0.222  0.499  1.0
  O  O28  1  0.518  0.157  0.791  1.0
  O  O29  1  0.837  0.490  0.208  1.0
  O  O30  1  0.052  0.691  0.791  1.0
  O  O31  1  0.302  0.955  0.208  1.0
  O  O32  1  0.572  0.711  0.717  1.0
  O  O33  1  0.284  0.433  0.282  1.0
[/CIF]
.