The material described by MgFe6(O5F)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(6), two equivalent O(3), and one F(2) atom to form distorted MgO3F tetrahedra that share  a cornercorner with one Fe(3)O4F2 octahedra,  a cornercorner with one Fe(2)O5F octahedra, corners with two equivalent Fe(1)O5F octahedra, and  an edgeedge with one Fe(1)O5F octahedra. The corner-sharing octahedral tilt angles range from 6-64°. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(6), two equivalent O(3), and one F(2) atom to form distorted FeO5F octahedra that share corners with two equivalent Mg(1)O3F tetrahedra,  an edgeedge with one Fe(3)O4F2 octahedra,  an edgeedge with one Fe(2)O5F octahedra, and  an edgeedge with one Mg(1)O3F tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(6), one O(7), two equivalent O(4), and one F(1) atom to form FeO5F octahedra that share  a cornercorner with one Mg(1)O3F tetrahedra,  an edgeedge with one Fe(3)O4F2 octahedra, and  an edgeedge with one Fe(1)O5F octahedra. In the third Fe site, Fe(3) is bonded to one O(2), one O(7), two equivalent O(5), one F(1), and one F(2) atom to form FeO4F2 octahedra that share  a cornercorner with one Mg(1)O3F tetrahedra,  an edgeedge with one Fe(1)O5F octahedra, and  an edgeedge with one Fe(2)O5F octahedra. In the fourth Fe site, Fe(4) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(3), and two equivalent O(4) atoms. In the fifth Fe site, Fe(5) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(3), and two equivalent O(5) atoms. In the sixth Fe site, Fe(6) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(4), and two equivalent O(5) atoms. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the third O site, O(3) is bonded to one Mg(1), one Fe(1), one Fe(4), and one Fe(5) atom to form a mixture of distorted corner and face-sharing OMgFe3 trigonal pyramids. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(3), one Fe(5), and one Fe(6) atom. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(3), and one Fe(6) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in an L-shaped geometry to one Fe(2) and one Fe(3) atom. In the second F site, F(2) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(3) atom. is represented by the CIF file [CIF]
data_MgFe6(O5F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.147
_cell_length_b   5.147
_cell_length_c   8.843
_cell_angle_alpha   89.845
_cell_angle_beta   90.155
_cell_angle_gamma   104.066
_symmetry_Int_Tables_number   1
_cell_volume   227.202
_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  0.692  0.308  0.002  1.0
  Fe  Fe1  1  0.038  0.962  0.008  1.0
  Fe  Fe2  1  0.993  0.007  0.332  1.0
  Fe  Fe3  1  0.000  1.000  0.661  1.0
  Fe  Fe4  1  0.416  0.584  0.187  1.0
  Fe  Fe5  1  0.410  0.590  0.814  1.0
  Fe  Fe6  1  0.585  0.415  0.501  1.0
  O  O7  1  0.185  0.815  0.177  1.0
  O  O8  1  0.174  0.826  0.830  1.0
  O  O9  1  0.309  0.318  0.995  1.0
  O  O10  1  0.319  0.299  0.337  1.0
  O  O11  1  0.310  0.305  0.665  1.0
  O  O12  1  0.682  0.691  0.995  1.0
  O  O13  1  0.701  0.681  0.337  1.0
  O  O14  1  0.695  0.690  0.665  1.0
  O  O15  1  0.859  0.141  0.153  1.0
  O  O16  1  0.828  0.172  0.501  1.0
  F  F17  1  0.166  0.834  0.500  1.0
  F  F18  1  0.831  0.169  0.831  1.0
[/CIF]
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The material described by MgFe6(O5F)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(6), two equivalent O(3), and one F(2) atom to form distorted MgO3F tetrahedra that share  a cornercorner with one Fe(3)O4F2 octahedra,  a cornercorner with one Fe(2)O5F octahedra, corners with two equivalent Fe(1)O5F octahedra, and  an edgeedge with one Fe(1)O5F octahedra. The corner-sharing octahedral tilt angles range from 6-64°. There are six inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(6), two equivalent O(3), and one F(2) atom to form distorted FeO5F octahedra that share corners with two equivalent Mg(1)O3F tetrahedra,  an edgeedge with one Fe(3)O4F2 octahedra,  an edgeedge with one Fe(2)O5F octahedra, and  an edgeedge with one Mg(1)O3F tetrahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(6), one O(7), two equivalent O(4), and one F(1) atom to form FeO5F octahedra that share  a cornercorner with one Mg(1)O3F tetrahedra,  an edgeedge with one Fe(3)O4F2 octahedra, and  an edgeedge with one Fe(1)O5F octahedra. In the third Fe site, Fe(3) is bonded to one O(2), one O(7), two equivalent O(5), one F(1), and one F(2) atom to form FeO4F2 octahedra that share  a cornercorner with one Mg(1)O3F tetrahedra,  an edgeedge with one Fe(1)O5F octahedra, and  an edgeedge with one Fe(2)O5F octahedra. In the fourth Fe site, Fe(4) is bonded in a 5-coordinate geometry to one O(1), two equivalent O(3), and two equivalent O(4) atoms. In the fifth Fe site, Fe(5) is bonded in a 5-coordinate geometry to one O(2), two equivalent O(3), and two equivalent O(5) atoms. In the sixth Fe site, Fe(6) is bonded in a 5-coordinate geometry to one O(7), two equivalent O(4), and two equivalent O(5) atoms. There are seven inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(1), one Fe(3), and one Fe(5) atom. In the third O site, O(3) is bonded to one Mg(1), one Fe(1), one Fe(4), and one Fe(5) atom to form a mixture of distorted corner and face-sharing OMgFe3 trigonal pyramids. In the fourth O site, O(4) is bonded in a trigonal planar geometry to one Fe(2), one Fe(4), and one Fe(6) atom. In the fifth O site, O(5) is bonded in a trigonal planar geometry to one Fe(3), one Fe(5), and one Fe(6) atom. In the sixth O site, O(6) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(2) atom. In the seventh O site, O(7) is bonded in a distorted T-shaped geometry to one Fe(2), one Fe(3), and one Fe(6) atom. There are two inequivalent F sites. In the first F site, F(1) is bonded in an L-shaped geometry to one Fe(2) and one Fe(3) atom. In the second F site, F(2) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(3) atom. is represented by the CIF file [CIF]
data_MgFe6(O5F)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.147
_cell_length_b   5.147
_cell_length_c   8.843
_cell_angle_alpha   89.845
_cell_angle_beta   90.155
_cell_angle_gamma   104.066
_symmetry_Int_Tables_number   1
_cell_volume   227.202
_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  0.692  0.308  0.002  1.0
  Fe  Fe1  1  0.038  0.962  0.008  1.0
  Fe  Fe2  1  0.993  0.007  0.332  1.0
  Fe  Fe3  1  0.000  1.000  0.661  1.0
  Fe  Fe4  1  0.416  0.584  0.187  1.0
  Fe  Fe5  1  0.410  0.590  0.814  1.0
  Fe  Fe6  1  0.585  0.415  0.501  1.0
  O  O7  1  0.185  0.815  0.177  1.0
  O  O8  1  0.174  0.826  0.830  1.0
  O  O9  1  0.309  0.318  0.995  1.0
  O  O10  1  0.319  0.299  0.337  1.0
  O  O11  1  0.310  0.305  0.665  1.0
  O  O12  1  0.682  0.691  0.995  1.0
  O  O13  1  0.701  0.681  0.337  1.0
  O  O14  1  0.695  0.690  0.665  1.0
  O  O15  1  0.859  0.141  0.153  1.0
  O  O16  1  0.828  0.172  0.501  1.0
  F  F17  1  0.166  0.834  0.500  1.0
  F  F18  1  0.831  0.169  0.831  1.0
[/CIF]
.