The crystal structure described by MgFe8(O7F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(10), one O(13), one O(14), one O(2), and one O(4) atom to form MgO6 octahedra that share corners with two equivalent Fe(2)O5F octahedra, corners with two equivalent Fe(8)O4F square pyramids,  an edgeedge with one Fe(3)O5F octahedra,  an edgeedge with one Fe(4)O5F octahedra, edges with two equivalent Fe(6)O5F octahedra, and  an edgeedge with one Fe(7)O5 square pyramid. The corner-sharing octahedral tilt angles range from 39-56°. There are eight inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 5-coordinate geometry to one O(10), one O(2), one O(3), one O(5), and one F(1) atom. 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 corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra, corners with two equivalent Fe(6)O5F octahedra, corners with two equivalent Fe(5)O6 octahedra, and  an edgeedge with one Fe(7)O5 square pyramid. The corner-sharing octahedral tilt angles range from 39-63°. In the third Fe site, Fe(3) is bonded to one O(1), one O(11), one O(4), one O(5), one O(8), and one F(2) atom to form FeO5F octahedra that share corners with two equivalent Fe(2)O5F octahedra, corners with two equivalent Fe(8)O4F square pyramids, corners with two equivalent Fe(7)O5 square pyramids,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(6)O5F octahedra, and  an edgeedge with one Fe(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-63°. In the fourth Fe site, Fe(4) is bonded to one O(10), one O(14), one O(6), one O(7), one O(9), and one F(1) atom to form FeO5F octahedra that share corners with two equivalent Fe(2)O5F octahedra,  a cornercorner with one Fe(8)O4F square pyramid,  a cornercorner with one Fe(7)O5 square pyramid,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(6)O5F octahedra, and  an edgeedge with one Fe(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-54°. In the fifth Fe site, Fe(5) is bonded to one O(12), one O(3), one O(5), one O(6), one O(8), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(2)O5F octahedra,  a cornercorner with one Fe(8)O4F square pyramid, corners with two equivalent Fe(7)O5 square pyramids,  an edgeedge with one Fe(3)O5F octahedra, and  an edgeedge with one Fe(4)O5F octahedra. The corner-sharing octahedral tilt angles range from 46-53°. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(13), one O(14), one O(2), one O(7), and one F(2) atom to form FeO5F octahedra that share corners with two equivalent Fe(2)O5F octahedra,  a cornercorner with one Fe(7)O5 square pyramid, corners with two equivalent Fe(8)O4F square pyramids,  an edgeedge with one Fe(3)O5F octahedra,  an edgeedge with one Fe(4)O5F octahedra, and edges with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-48°. In the seventh Fe site, Fe(7) is bonded to one O(11), one O(12), one O(13), one O(4), and one O(9) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Fe(4)O5F octahedra,  a cornercorner with one Fe(6)O5F octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(5)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(2)O5F octahedra, and  an edgeedge with one Fe(8)O4F square pyramid. The corner-sharing octahedral tilt angles range from 45-50°. In the eighth Fe site, Fe(8) is bonded to one O(11), one O(13), one O(2), one O(8), and one F(1) atom to form distorted FeO4F square pyramids that share  a cornercorner with one Fe(4)O5F octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(6)O5F octahedra, and  an edgeedge with one Fe(7)O5 square pyramid. The corner-sharing octahedral tilt angles range from 38-59°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Mg(1), one Fe(3), and one Fe(6) atom. In the second O site, O(2) is bonded to one Mg(1), one Fe(1), one Fe(6), and one Fe(8) atom to form edge-sharing OMgFe3 trigonal pyramids. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(5) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), 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 water-like geometry to one Fe(4) and one Fe(5) atom. In the seventh O site, O(7) is bonded in a distorted 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 trigonal planar geometry to 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 to one Mg(1), one Fe(1), one Fe(2), and one Fe(4) atom to form edge-sharing OMgFe3 trigonal pyramids. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to 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 rectangular see-saw-like geometry to one Mg(1), one Fe(6), one Fe(7), and one Fe(8) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Fe(4), and one Fe(6) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(8) atom. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one Fe(6) atom. is represented by the CIF card [CIF]
data_MgFe8(O7F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.940
_cell_length_b   7.175
_cell_length_c   5.806
_cell_angle_alpha   109.873
_cell_angle_beta   115.437
_cell_angle_gamma   78.956
_symmetry_Int_Tables_number   1
_cell_volume   280.517
_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  0.989  0.993  0.481  1.0
  Fe  Fe1  1  0.684  0.270  0.531  1.0
  Fe  Fe2  1  0.525  1.000  0.975  1.0
  Fe  Fe3  1  0.253  0.251  0.497  1.0
  Fe  Fe4  1  0.723  0.762  0.488  1.0
  Fe  Fe5  1  0.493  0.499  0.009  1.0
  Fe  Fe6  1  0.989  0.996  0.984  1.0
  Fe  Fe7  1  0.294  0.723  0.485  1.0
  Fe  Fe8  1  0.052  0.478  0.973  1.0
  O  O9  1  0.991  0.178  0.298  1.0
  O  O10  1  0.944  0.212  0.799  1.0
  O  O11  1  0.548  0.289  0.164  1.0
  O  O12  1  0.296  0.005  0.641  1.0
  O  O13  1  0.516  0.313  0.697  1.0
  O  O14  1  0.736  0.573  0.187  1.0
  O  O15  1  0.718  0.936  0.821  1.0
  O  O16  1  0.236  0.438  0.831  1.0
  O  O17  1  0.475  0.686  0.327  1.0
  O  O18  1  0.696  0.987  0.334  1.0
  O  O19  1  0.203  0.469  0.334  1.0
  O  O20  1  0.442  0.714  0.838  1.0
  O  O21  1  0.067  0.776  0.181  1.0
  O  O22  1  0.988  0.806  0.668  1.0
  F  F23  1  0.803  0.532  0.687  1.0
  F  F24  1  0.272  0.058  0.151  1.0
[/CIF]
.
The crystal structure described by MgFe8(O7F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(10), one O(13), one O(14), one O(2), and one O(4) atom to form MgO6 octahedra that share corners with two equivalent Fe(2)O5F octahedra, corners with two equivalent Fe(8)O4F square pyramids,  an edgeedge with one Fe(3)O5F octahedra,  an edgeedge with one Fe(4)O5F octahedra, edges with two equivalent Fe(6)O5F octahedra, and  an edgeedge with one Fe(7)O5 square pyramid. The corner-sharing octahedral tilt angles range from 39-56°. There are eight inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 5-coordinate geometry to one O(10), one O(2), one O(3), one O(5), and one F(1) atom. 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 corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra, corners with two equivalent Fe(6)O5F octahedra, corners with two equivalent Fe(5)O6 octahedra, and  an edgeedge with one Fe(7)O5 square pyramid. The corner-sharing octahedral tilt angles range from 39-63°. In the third Fe site, Fe(3) is bonded to one O(1), one O(11), one O(4), one O(5), one O(8), and one F(2) atom to form FeO5F octahedra that share corners with two equivalent Fe(2)O5F octahedra, corners with two equivalent Fe(8)O4F square pyramids, corners with two equivalent Fe(7)O5 square pyramids,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(6)O5F octahedra, and  an edgeedge with one Fe(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-63°. In the fourth Fe site, Fe(4) is bonded to one O(10), one O(14), one O(6), one O(7), one O(9), and one F(1) atom to form FeO5F octahedra that share corners with two equivalent Fe(2)O5F octahedra,  a cornercorner with one Fe(8)O4F square pyramid,  a cornercorner with one Fe(7)O5 square pyramid,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(6)O5F octahedra, and  an edgeedge with one Fe(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 48-54°. In the fifth Fe site, Fe(5) is bonded to one O(12), one O(3), one O(5), one O(6), one O(8), and one O(9) atom to form FeO6 octahedra that share corners with two equivalent Fe(2)O5F octahedra,  a cornercorner with one Fe(8)O4F square pyramid, corners with two equivalent Fe(7)O5 square pyramids,  an edgeedge with one Fe(3)O5F octahedra, and  an edgeedge with one Fe(4)O5F octahedra. The corner-sharing octahedral tilt angles range from 46-53°. In the sixth Fe site, Fe(6) is bonded to one O(1), one O(13), one O(14), one O(2), one O(7), and one F(2) atom to form FeO5F octahedra that share corners with two equivalent Fe(2)O5F octahedra,  a cornercorner with one Fe(7)O5 square pyramid, corners with two equivalent Fe(8)O4F square pyramids,  an edgeedge with one Fe(3)O5F octahedra,  an edgeedge with one Fe(4)O5F octahedra, and edges with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-48°. In the seventh Fe site, Fe(7) is bonded to one O(11), one O(12), one O(13), one O(4), and one O(9) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Fe(4)O5F octahedra,  a cornercorner with one Fe(6)O5F octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(5)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Fe(2)O5F octahedra, and  an edgeedge with one Fe(8)O4F square pyramid. The corner-sharing octahedral tilt angles range from 45-50°. In the eighth Fe site, Fe(8) is bonded to one O(11), one O(13), one O(2), one O(8), and one F(1) atom to form distorted FeO4F square pyramids that share  a cornercorner with one Fe(4)O5F octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(6)O5F octahedra, and  an edgeedge with one Fe(7)O5 square pyramid. The corner-sharing octahedral tilt angles range from 38-59°. There are fourteen inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to one Mg(1), one Fe(3), and one Fe(6) atom. In the second O site, O(2) is bonded to one Mg(1), one Fe(1), one Fe(6), and one Fe(8) atom to form edge-sharing OMgFe3 trigonal pyramids. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(5) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), 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 water-like geometry to one Fe(4) and one Fe(5) atom. In the seventh O site, O(7) is bonded in a distorted 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 trigonal planar geometry to 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 to one Mg(1), one Fe(1), one Fe(2), and one Fe(4) atom to form edge-sharing OMgFe3 trigonal pyramids. In the eleventh O site, O(11) is bonded in a distorted trigonal planar geometry to 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 rectangular see-saw-like geometry to one Mg(1), one Fe(6), one Fe(7), and one Fe(8) atom. In the fourteenth O site, O(14) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Fe(4), and one Fe(6) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in a trigonal planar geometry to one Fe(1), one Fe(4), and one Fe(8) atom. In the second F site, F(2) is bonded in a 3-coordinate geometry to one Fe(2), one Fe(3), and one Fe(6) atom. is represented by the CIF card [CIF]
data_MgFe8(O7F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.940
_cell_length_b   7.175
_cell_length_c   5.806
_cell_angle_alpha   109.873
_cell_angle_beta   115.437
_cell_angle_gamma   78.956
_symmetry_Int_Tables_number   1
_cell_volume   280.517
_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  0.989  0.993  0.481  1.0
  Fe  Fe1  1  0.684  0.270  0.531  1.0
  Fe  Fe2  1  0.525  1.000  0.975  1.0
  Fe  Fe3  1  0.253  0.251  0.497  1.0
  Fe  Fe4  1  0.723  0.762  0.488  1.0
  Fe  Fe5  1  0.493  0.499  0.009  1.0
  Fe  Fe6  1  0.989  0.996  0.984  1.0
  Fe  Fe7  1  0.294  0.723  0.485  1.0
  Fe  Fe8  1  0.052  0.478  0.973  1.0
  O  O9  1  0.991  0.178  0.298  1.0
  O  O10  1  0.944  0.212  0.799  1.0
  O  O11  1  0.548  0.289  0.164  1.0
  O  O12  1  0.296  0.005  0.641  1.0
  O  O13  1  0.516  0.313  0.697  1.0
  O  O14  1  0.736  0.573  0.187  1.0
  O  O15  1  0.718  0.936  0.821  1.0
  O  O16  1  0.236  0.438  0.831  1.0
  O  O17  1  0.475  0.686  0.327  1.0
  O  O18  1  0.696  0.987  0.334  1.0
  O  O19  1  0.203  0.469  0.334  1.0
  O  O20  1  0.442  0.714  0.838  1.0
  O  O21  1  0.067  0.776  0.181  1.0
  O  O22  1  0.988  0.806  0.668  1.0
  F  F23  1  0.803  0.532  0.687  1.0
  F  F24  1  0.272  0.058  0.151  1.0
[/CIF]
.