The material described by MgFe8(O7F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(11), one O(2), one O(3), one O(6), and one F(1) atom to form MgO5F octahedra that share  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(8)O4F trigonal bipyramid,  a cornercorner with one Fe(7)O5 trigonal bipyramid,  an edgeedge with one Fe(3)O5F octahedra,  an edgeedge with one Fe(4)O5F octahedra,  an edgeedge with one Fe(6)O5F octahedra,  an edgeedge with one Fe(5)O6 octahedra, and  an edgeedge with one Fe(8)O4F trigonal bipyramid. 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), and one O(7) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(3)O5F octahedra,  a cornercorner with one Fe(6)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra, corners with two equivalent Fe(5)O6 octahedra, and  an edgeedge with one Fe(7)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-58°. 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  a cornercorner with one Fe(2)O5 square pyramid, corners with two equivalent Fe(8)O4F trigonal bipyramids, corners with two equivalent Fe(7)O5 trigonal bipyramids,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(6)O5F octahedra, and  an edgeedge with one Fe(5)O6 octahedra. 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 distorted FeO5F octahedra that share corners with two equivalent Fe(2)O5 square pyramids,  a cornercorner with one Fe(8)O4F trigonal bipyramid,  a cornercorner with one Fe(7)O5 trigonal bipyramid,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(6)O5F octahedra, and  an edgeedge with one Fe(5)O6 octahedra. 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)O5 square pyramids,  a cornercorner with one Fe(8)O4F trigonal bipyramid,  a cornercorner with one Fe(7)O5 trigonal bipyramid,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(3)O5F octahedra, and  an edgeedge with one Fe(4)O5F octahedra. 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  a cornercorner with one Fe(2)O5 square pyramid, corners with two equivalent Fe(8)O4F trigonal bipyramids, corners with two equivalent Fe(7)O5 trigonal bipyramids,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(3)O5F octahedra, and  an edgeedge with one Fe(4)O5F octahedra. In the seventh Fe site, Fe(7) is bonded to one O(11), one O(12), one O(13), one O(14), and one O(4) atom to form distorted FeO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(4)O5F octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(6)O5F octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(8)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-59°. 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 trigonal bipyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(4)O5F octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(6)O5F octahedra,  an edgeedge with one Mg(1)O5F octahedra, and  an edgeedge with one Fe(7)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 47-56°. 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 distorted OMgFe3 trigonal pyramids that share  a cornercorner with one F(1)MgFe3 trigonal pyramid, corners with two equivalent O(3)MgFe3 trigonal pyramids,  an edgeedge with one O(11)MgFe3 trigonal pyramid, and  an edgeedge with one F(1)MgFe3 trigonal pyramid. In the third O site, O(3) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(5) atom to form distorted OMgFe3 trigonal pyramids that share  a cornercorner with one O(11)MgFe3 trigonal pyramid, corners with two equivalent O(2)MgFe3 trigonal pyramids, and  an edgeedge with one F(1)MgFe3 trigonal pyramid. In the fourth O site, O(4) is bonded in a trigonal planar geometry to 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 trigonal non-coplanar geometry to one Mg(1), 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 water-like geometry to one Fe(4) and one Fe(5) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the eleventh O site, O(11) is bonded to one Mg(1), one Fe(3), one Fe(7), and one Fe(8) atom to form OMgFe3 trigonal pyramids that share  a cornercorner with one O(3)MgFe3 trigonal pyramid, corners with two equivalent F(1)MgFe3 trigonal pyramids, and  an edgeedge with one O(2)MgFe3 trigonal pyramid. In the twelfth O site, O(12) is bonded in a 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 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 to one Mg(1), one Fe(1), one Fe(4), and one Fe(8) atom to form distorted FMgFe3 trigonal pyramids that share  a cornercorner with one O(2)MgFe3 trigonal pyramid, corners with two equivalent O(11)MgFe3 trigonal pyramids,  an edgeedge with one O(2)MgFe3 trigonal pyramid, and  an edgeedge with one O(3)MgFe3 trigonal pyramid. In the second F site, F(2) is bonded in an L-shaped geometry to one Fe(3) and one Fe(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe8(O7F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.962
_cell_length_b   7.315
_cell_length_c   5.746
_cell_angle_alpha   108.758
_cell_angle_beta   114.095
_cell_angle_gamma   83.784
_symmetry_Int_Tables_number   1
_cell_volume   289.184
_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  0.874  0.369  0.244  1.0
  Fe  Fe1  1  0.700  0.256  0.549  1.0
  Fe  Fe2  1  0.539  0.997  0.976  1.0
  Fe  Fe3  1  0.259  0.244  0.516  1.0
  Fe  Fe4  1  0.737  0.779  0.491  1.0
  Fe  Fe5  1  0.499  0.522  0.008  1.0
  Fe  Fe6  1  0.006  0.979  0.011  1.0
  Fe  Fe7  1  0.202  0.767  0.530  1.0
  Fe  Fe8  1  0.070  0.480  0.991  1.0
  O  O9  1  0.013  0.150  0.354  1.0
  O  O10  1  0.906  0.259  0.886  1.0
  O  O11  1  0.616  0.267  0.163  1.0
  O  O12  1  0.337  0.017  0.655  1.0
  O  O13  1  0.509  0.352  0.674  1.0
  O  O14  1  0.745  0.608  0.164  1.0
  O  O15  1  0.735  0.911  0.829  1.0
  O  O16  1  0.261  0.418  0.868  1.0
  O  O17  1  0.507  0.658  0.346  1.0
  O  O18  1  0.653  0.990  0.337  1.0
  O  O19  1  0.147  0.484  0.369  1.0
  O  O20  1  0.410  0.751  0.849  1.0
  O  O21  1  0.091  0.758  0.158  1.0
  O  O22  1  0.996  0.836  0.649  1.0
  F  F23  1  0.860  0.495  0.621  1.0
  F  F24  1  0.263  0.098  0.152  1.0
[/CIF]
.
The material described by MgFe8(O7F)2 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(11), one O(2), one O(3), one O(6), and one F(1) atom to form MgO5F octahedra that share  a cornercorner with one Fe(2)O5 square pyramid,  a cornercorner with one Fe(8)O4F trigonal bipyramid,  a cornercorner with one Fe(7)O5 trigonal bipyramid,  an edgeedge with one Fe(3)O5F octahedra,  an edgeedge with one Fe(4)O5F octahedra,  an edgeedge with one Fe(6)O5F octahedra,  an edgeedge with one Fe(5)O6 octahedra, and  an edgeedge with one Fe(8)O4F trigonal bipyramid. 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), and one O(7) atom to form distorted FeO5 square pyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(3)O5F octahedra,  a cornercorner with one Fe(6)O5F octahedra, corners with two equivalent Fe(4)O5F octahedra, corners with two equivalent Fe(5)O6 octahedra, and  an edgeedge with one Fe(7)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-58°. 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  a cornercorner with one Fe(2)O5 square pyramid, corners with two equivalent Fe(8)O4F trigonal bipyramids, corners with two equivalent Fe(7)O5 trigonal bipyramids,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(6)O5F octahedra, and  an edgeedge with one Fe(5)O6 octahedra. 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 distorted FeO5F octahedra that share corners with two equivalent Fe(2)O5 square pyramids,  a cornercorner with one Fe(8)O4F trigonal bipyramid,  a cornercorner with one Fe(7)O5 trigonal bipyramid,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(6)O5F octahedra, and  an edgeedge with one Fe(5)O6 octahedra. 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)O5 square pyramids,  a cornercorner with one Fe(8)O4F trigonal bipyramid,  a cornercorner with one Fe(7)O5 trigonal bipyramid,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(3)O5F octahedra, and  an edgeedge with one Fe(4)O5F octahedra. 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  a cornercorner with one Fe(2)O5 square pyramid, corners with two equivalent Fe(8)O4F trigonal bipyramids, corners with two equivalent Fe(7)O5 trigonal bipyramids,  an edgeedge with one Mg(1)O5F octahedra,  an edgeedge with one Fe(3)O5F octahedra, and  an edgeedge with one Fe(4)O5F octahedra. In the seventh Fe site, Fe(7) is bonded to one O(11), one O(12), one O(13), one O(14), and one O(4) atom to form distorted FeO5 trigonal bipyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(4)O5F octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(6)O5F octahedra,  an edgeedge with one Fe(2)O5 square pyramid, and  an edgeedge with one Fe(8)O4F trigonal bipyramid. The corner-sharing octahedral tilt angles range from 44-59°. 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 trigonal bipyramids that share  a cornercorner with one Mg(1)O5F octahedra,  a cornercorner with one Fe(4)O5F octahedra,  a cornercorner with one Fe(5)O6 octahedra, corners with two equivalent Fe(3)O5F octahedra, corners with two equivalent Fe(6)O5F octahedra,  an edgeedge with one Mg(1)O5F octahedra, and  an edgeedge with one Fe(7)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 47-56°. 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 distorted OMgFe3 trigonal pyramids that share  a cornercorner with one F(1)MgFe3 trigonal pyramid, corners with two equivalent O(3)MgFe3 trigonal pyramids,  an edgeedge with one O(11)MgFe3 trigonal pyramid, and  an edgeedge with one F(1)MgFe3 trigonal pyramid. In the third O site, O(3) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(5) atom to form distorted OMgFe3 trigonal pyramids that share  a cornercorner with one O(11)MgFe3 trigonal pyramid, corners with two equivalent O(2)MgFe3 trigonal pyramids, and  an edgeedge with one F(1)MgFe3 trigonal pyramid. In the fourth O site, O(4) is bonded in a trigonal planar geometry to 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 trigonal non-coplanar geometry to one Mg(1), 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 water-like geometry to one Fe(4) and one Fe(5) atom. In the tenth O site, O(10) is bonded in a trigonal planar geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the eleventh O site, O(11) is bonded to one Mg(1), one Fe(3), one Fe(7), and one Fe(8) atom to form OMgFe3 trigonal pyramids that share  a cornercorner with one O(3)MgFe3 trigonal pyramid, corners with two equivalent F(1)MgFe3 trigonal pyramids, and  an edgeedge with one O(2)MgFe3 trigonal pyramid. In the twelfth O site, O(12) is bonded in a 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 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 to one Mg(1), one Fe(1), one Fe(4), and one Fe(8) atom to form distorted FMgFe3 trigonal pyramids that share  a cornercorner with one O(2)MgFe3 trigonal pyramid, corners with two equivalent O(11)MgFe3 trigonal pyramids,  an edgeedge with one O(2)MgFe3 trigonal pyramid, and  an edgeedge with one O(3)MgFe3 trigonal pyramid. In the second F site, F(2) is bonded in an L-shaped geometry to one Fe(3) and one Fe(6) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe8(O7F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.962
_cell_length_b   7.315
_cell_length_c   5.746
_cell_angle_alpha   108.758
_cell_angle_beta   114.095
_cell_angle_gamma   83.784
_symmetry_Int_Tables_number   1
_cell_volume   289.184
_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  0.874  0.369  0.244  1.0
  Fe  Fe1  1  0.700  0.256  0.549  1.0
  Fe  Fe2  1  0.539  0.997  0.976  1.0
  Fe  Fe3  1  0.259  0.244  0.516  1.0
  Fe  Fe4  1  0.737  0.779  0.491  1.0
  Fe  Fe5  1  0.499  0.522  0.008  1.0
  Fe  Fe6  1  0.006  0.979  0.011  1.0
  Fe  Fe7  1  0.202  0.767  0.530  1.0
  Fe  Fe8  1  0.070  0.480  0.991  1.0
  O  O9  1  0.013  0.150  0.354  1.0
  O  O10  1  0.906  0.259  0.886  1.0
  O  O11  1  0.616  0.267  0.163  1.0
  O  O12  1  0.337  0.017  0.655  1.0
  O  O13  1  0.509  0.352  0.674  1.0
  O  O14  1  0.745  0.608  0.164  1.0
  O  O15  1  0.735  0.911  0.829  1.0
  O  O16  1  0.261  0.418  0.868  1.0
  O  O17  1  0.507  0.658  0.346  1.0
  O  O18  1  0.653  0.990  0.337  1.0
  O  O19  1  0.147  0.484  0.369  1.0
  O  O20  1  0.410  0.751  0.849  1.0
  O  O21  1  0.091  0.758  0.158  1.0
  O  O22  1  0.996  0.836  0.649  1.0
  F  F23  1  0.860  0.495  0.621  1.0
  F  F24  1  0.263  0.098  0.152  1.0
[/CIF]
.