The material structure described by MgFe8(O7F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(11), one O(2), one O(3), one O(4), one O(8), and one F(2) atom to form distorted MgO5F octahedra that share corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(7)O6 octahedra,  a cornercorner with one Fe(3)O4F square pyramid,  a cornercorner with one Fe(6)O4F square pyramid,  a cornercorner with one Fe(5)O5 square pyramid,  an edgeedge with one Fe(3)O4F square pyramid,  a faceface with one Fe(2)O5F octahedra, and  a faceface with one Fe(8)O5F octahedra. The corner-sharing octahedral tilt angles range from 37-44°. There are eight inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(5), and one F(1) atom to form FeO5F octahedra that share corners with two equivalent Mg(1)O5F octahedra,  a cornercorner with one Fe(6)O4F square pyramid,  a cornercorner with one Fe(5)O5 square pyramid, corners with two equivalent Fe(3)O4F square pyramids,  an edgeedge with one Fe(2)O5F octahedra, and  an edgeedge with one Fe(8)O5F octahedra. The corner-sharing octahedral tilt angles range from 37-44°. In the second Fe site, Fe(2) is bonded to one O(10), one O(12), one O(3), one O(4), one O(7), and one F(2) atom to form distorted FeO5F octahedra that share  a cornercorner with one Fe(3)O4F square pyramid,  a cornercorner with one Fe(5)O5 square pyramid, corners with two equivalent Fe(6)O4F square pyramids,  an edgeedge with one Fe(1)O5F octahedra,  an edgeedge with one Fe(7)O6 octahedra, and  a faceface with one Mg(1)O5F octahedra. In the third Fe site, Fe(3) is bonded to one O(1), one O(11), one O(5), one O(8), and one F(2) atom to form distorted FeO4F square pyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(2)O5F octahedra,  a cornercorner with one Fe(7)O6 octahedra, corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(8)O5F octahedra,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(6)O4F square pyramid, and  an edgeedge with one Fe(5)O5 square pyramid. The corner-sharing octahedral tilt angles range from 44-77°. In the fourth Fe site, Fe(4) is bonded in a 6-coordinate geometry to one O(10), one O(14), one O(6), one O(7), one O(9), and one F(1) atom. In the fifth Fe site, Fe(5) is bonded to one O(12), one O(5), one O(6), one O(8), and one O(9) atom to form FeO5 square pyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(1)O5F octahedra,  a cornercorner with one Fe(2)O5F octahedra, corners with two equivalent Fe(8)O5F octahedra, corners with two equivalent Fe(7)O6 octahedra, and  an edgeedge with one Fe(3)O4F square pyramid. The corner-sharing octahedral tilt angles range from 44-72°. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(13), one O(14), one O(7), and one F(2) atom to form distorted FeO4F square pyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(1)O5F octahedra,  a cornercorner with one Fe(8)O5F octahedra, corners with two equivalent Fe(2)O5F octahedra, corners with two equivalent Fe(7)O6 octahedra, and  an edgeedge with one Fe(3)O4F square pyramid. The corner-sharing octahedral tilt angles range from 44-67°. In the seventh Fe site, Fe(7) is bonded to one O(11), one O(12), one O(13), one O(14), one O(4), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Mg(1)O5F octahedra,  a cornercorner with one Fe(3)O4F square pyramid, corners with two equivalent Fe(6)O4F square pyramids, corners with two equivalent Fe(5)O5 square pyramids,  an edgeedge with one Fe(2)O5F octahedra, and  an edgeedge with one Fe(8)O5F octahedra. The corner-sharing octahedral tilt angles range from 41-44°. In the eighth Fe site, Fe(8) is bonded to one O(11), one O(13), one O(2), one O(6), one O(8), and one F(1) atom to form FeO5F octahedra that share  a cornercorner with one Fe(6)O4F square pyramid, corners with two equivalent Fe(3)O4F square pyramids, corners with two equivalent Fe(5)O5 square pyramids,  an edgeedge with one Fe(1)O5F octahedra,  an edgeedge with one Fe(7)O6 octahedra, and  a faceface with one Mg(1)O5F octahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(6) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(8) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(2) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Mg(1), one Fe(2), and one Fe(7) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Fe(4), one Fe(5), and one Fe(8) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the eighth O site, O(8) is bonded in a distorted tetrahedral geometry to one Mg(1), one Fe(3), one Fe(5), and one Fe(8) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(4), one Fe(5), and one Fe(7) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the eleventh O site, O(11) is bonded in a distorted see-saw-like geometry to one Mg(1), one Fe(3), one Fe(7), and one Fe(8) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(5), and one Fe(7) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Fe(6), one Fe(7), and one Fe(8) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Fe(4), one Fe(6), and one Fe(7) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted L-shaped geometry to one Fe(1), one Fe(4), and one Fe(8) atom. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(6) atom. is represented by the CIF file [CIF]
data_MgFe8(O7F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.309
_cell_length_b   8.044
_cell_length_c   5.920
_cell_angle_alpha   115.843
_cell_angle_beta   111.195
_cell_angle_gamma   79.241
_symmetry_Int_Tables_number   1
_cell_volume   291.893
_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
  Mg  Mg0  1  0.257  0.237  0.965  1.0
  Fe  Fe1  1  0.754  0.237  0.494  1.0
  Fe  Fe2  1  0.543  0.964  0.991  1.0
  Fe  Fe3  1  0.224  0.311  0.482  1.0
  Fe  Fe4  1  0.757  0.776  0.477  1.0
  Fe  Fe5  1  0.500  0.533  0.974  1.0
  Fe  Fe6  1  0.009  0.951  0.036  1.0
  Fe  Fe7  1  0.260  0.745  0.504  1.0
  Fe  Fe8  1  0.984  0.521  0.997  1.0
  O  O9  1  0.986  0.178  0.343  1.0
  O  O10  1  0.953  0.259  0.829  1.0
  O  O11  1  0.559  0.222  0.154  1.0
  O  O12  1  0.341  0.999  0.707  1.0
  O  O13  1  0.519  0.335  0.656  1.0
  O  O14  1  0.773  0.576  0.152  1.0
  O  O15  1  0.740  0.915  0.818  1.0
  O  O16  1  0.239  0.443  0.850  1.0
  O  O17  1  0.492  0.686  0.325  1.0
  O  O18  1  0.697  0.968  0.326  1.0
  O  O19  1  0.193  0.472  0.303  1.0
  O  O20  1  0.444  0.726  0.836  1.0
  O  O21  1  0.079  0.767  0.175  1.0
  O  O22  1  0.029  0.811  0.661  1.0
  F  F23  1  0.816  0.515  0.642  1.0
  F  F24  1  0.268  0.075  0.161  1.0
[/CIF]
.
The material structure described by MgFe8(O7F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(11), one O(2), one O(3), one O(4), one O(8), and one F(2) atom to form distorted MgO5F octahedra that share corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(7)O6 octahedra,  a cornercorner with one Fe(3)O4F square pyramid,  a cornercorner with one Fe(6)O4F square pyramid,  a cornercorner with one Fe(5)O5 square pyramid,  an edgeedge with one Fe(3)O4F square pyramid,  a faceface with one Fe(2)O5F octahedra, and  a faceface with one Fe(8)O5F octahedra. The corner-sharing octahedral tilt angles range from 37-44°. There are eight inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(10), one O(2), one O(3), one O(5), and one F(1) atom to form FeO5F octahedra that share corners with two equivalent Mg(1)O5F octahedra,  a cornercorner with one Fe(6)O4F square pyramid,  a cornercorner with one Fe(5)O5 square pyramid, corners with two equivalent Fe(3)O4F square pyramids,  an edgeedge with one Fe(2)O5F octahedra, and  an edgeedge with one Fe(8)O5F octahedra. The corner-sharing octahedral tilt angles range from 37-44°. In the second Fe site, Fe(2) is bonded to one O(10), one O(12), one O(3), one O(4), one O(7), and one F(2) atom to form distorted FeO5F octahedra that share  a cornercorner with one Fe(3)O4F square pyramid,  a cornercorner with one Fe(5)O5 square pyramid, corners with two equivalent Fe(6)O4F square pyramids,  an edgeedge with one Fe(1)O5F octahedra,  an edgeedge with one Fe(7)O6 octahedra, and  a faceface with one Mg(1)O5F octahedra. In the third Fe site, Fe(3) is bonded to one O(1), one O(11), one O(5), one O(8), and one F(2) atom to form distorted FeO4F square pyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(2)O5F octahedra,  a cornercorner with one Fe(7)O6 octahedra, corners with two equivalent Fe(1)O5F octahedra, corners with two equivalent Fe(8)O5F octahedra,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(6)O4F square pyramid, and  an edgeedge with one Fe(5)O5 square pyramid. The corner-sharing octahedral tilt angles range from 44-77°. In the fourth Fe site, Fe(4) is bonded in a 6-coordinate geometry to one O(10), one O(14), one O(6), one O(7), one O(9), and one F(1) atom. In the fifth Fe site, Fe(5) is bonded to one O(12), one O(5), one O(6), one O(8), and one O(9) atom to form FeO5 square pyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(1)O5F octahedra,  a cornercorner with one Fe(2)O5F octahedra, corners with two equivalent Fe(8)O5F octahedra, corners with two equivalent Fe(7)O6 octahedra, and  an edgeedge with one Fe(3)O4F square pyramid. The corner-sharing octahedral tilt angles range from 44-72°. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(13), one O(14), one O(7), and one F(2) atom to form distorted FeO4F square pyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(1)O5F octahedra,  a cornercorner with one Fe(8)O5F octahedra, corners with two equivalent Fe(2)O5F octahedra, corners with two equivalent Fe(7)O6 octahedra, and  an edgeedge with one Fe(3)O4F square pyramid. The corner-sharing octahedral tilt angles range from 44-67°. In the seventh Fe site, Fe(7) is bonded to one O(11), one O(12), one O(13), one O(14), one O(4), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Mg(1)O5F octahedra,  a cornercorner with one Fe(3)O4F square pyramid, corners with two equivalent Fe(6)O4F square pyramids, corners with two equivalent Fe(5)O5 square pyramids,  an edgeedge with one Fe(2)O5F octahedra, and  an edgeedge with one Fe(8)O5F octahedra. The corner-sharing octahedral tilt angles range from 41-44°. In the eighth Fe site, Fe(8) is bonded to one O(11), one O(13), one O(2), one O(6), one O(8), and one F(1) atom to form FeO5F octahedra that share  a cornercorner with one Fe(6)O4F square pyramid, corners with two equivalent Fe(3)O4F square pyramids, corners with two equivalent Fe(5)O5 square pyramids,  an edgeedge with one Fe(1)O5F octahedra,  an edgeedge with one Fe(7)O6 octahedra, and  a faceface with one Mg(1)O5F octahedra. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(6) atom. In the second O site, O(2) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(8) atom. In the third O site, O(3) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(2) atom. In the fourth O site, O(4) is bonded in a T-shaped geometry to one Mg(1), one Fe(2), and one Fe(7) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the sixth O site, O(6) is bonded in a trigonal planar geometry to one Fe(4), one Fe(5), and one Fe(8) atom. In the seventh O site, O(7) is bonded in a trigonal planar geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the eighth O site, O(8) is bonded in a distorted tetrahedral geometry to one Mg(1), one Fe(3), one Fe(5), and one Fe(8) atom. In the ninth O site, O(9) is bonded in a distorted trigonal planar geometry to one Fe(4), one Fe(5), and one Fe(7) atom. In the tenth O site, O(10) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the eleventh O site, O(11) is bonded in a distorted see-saw-like geometry to one Mg(1), one Fe(3), one Fe(7), and one Fe(8) atom. In the twelfth O site, O(12) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(5), and one Fe(7) atom. In the thirteenth O site, O(13) is bonded in a distorted trigonal planar geometry to one Fe(6), one Fe(7), and one Fe(8) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal planar geometry to one Fe(4), one Fe(6), and one Fe(7) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted L-shaped geometry to one Fe(1), one Fe(4), and one Fe(8) atom. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(6) atom. is represented by the CIF file [CIF]
data_MgFe8(O7F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.309
_cell_length_b   8.044
_cell_length_c   5.920
_cell_angle_alpha   115.843
_cell_angle_beta   111.195
_cell_angle_gamma   79.241
_symmetry_Int_Tables_number   1
_cell_volume   291.893
_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
  Mg  Mg0  1  0.257  0.237  0.965  1.0
  Fe  Fe1  1  0.754  0.237  0.494  1.0
  Fe  Fe2  1  0.543  0.964  0.991  1.0
  Fe  Fe3  1  0.224  0.311  0.482  1.0
  Fe  Fe4  1  0.757  0.776  0.477  1.0
  Fe  Fe5  1  0.500  0.533  0.974  1.0
  Fe  Fe6  1  0.009  0.951  0.036  1.0
  Fe  Fe7  1  0.260  0.745  0.504  1.0
  Fe  Fe8  1  0.984  0.521  0.997  1.0
  O  O9  1  0.986  0.178  0.343  1.0
  O  O10  1  0.953  0.259  0.829  1.0
  O  O11  1  0.559  0.222  0.154  1.0
  O  O12  1  0.341  0.999  0.707  1.0
  O  O13  1  0.519  0.335  0.656  1.0
  O  O14  1  0.773  0.576  0.152  1.0
  O  O15  1  0.740  0.915  0.818  1.0
  O  O16  1  0.239  0.443  0.850  1.0
  O  O17  1  0.492  0.686  0.325  1.0
  O  O18  1  0.697  0.968  0.326  1.0
  O  O19  1  0.193  0.472  0.303  1.0
  O  O20  1  0.444  0.726  0.836  1.0
  O  O21  1  0.079  0.767  0.175  1.0
  O  O22  1  0.029  0.811  0.661  1.0
  F  F23  1  0.816  0.515  0.642  1.0
  F  F24  1  0.268  0.075  0.161  1.0
[/CIF]
.