The compound described by MgFe4(OF)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(3), one O(4), one F(1), one F(3), and one F(4) atom to form MgO3F3 octahedra that share  a cornercorner with one Fe(2)O3F2 trigonal bipyramid,  a cornercorner with one Fe(4)O3F2 trigonal bipyramid, corners with four equivalent Fe(3)O3F2 trigonal bipyramids,  an edgeedge with one Fe(1)O3F2 trigonal bipyramid,  an edgeedge with one Fe(2)O3F2 trigonal bipyramid,  an edgeedge with one Fe(4)O3F2 trigonal bipyramid, and  a faceface with one Fe(1)O3F2 trigonal bipyramid. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(3), one O(4), one F(1), and one F(3) atom to form distorted FeO3F2 trigonal bipyramids that share corners with two equivalent Fe(2)O3F2 trigonal bipyramids, corners with two equivalent Fe(4)O3F2 trigonal bipyramids,  an edgeedge with one Mg(1)O3F3 octahedra, edges with two equivalent Fe(3)O3F2 trigonal bipyramids, and  a faceface with one Mg(1)O3F3 octahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(4), one F(2), and one F(4) atom to form FeO3F2 trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Fe(1)O3F2 trigonal bipyramids, corners with two equivalent Fe(3)O3F2 trigonal bipyramids,  an edgeedge with one Mg(1)O3F3 octahedra, and edges with two equivalent Fe(4)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(3), one F(1), and one F(3) atom to form distorted FeO3F2 trigonal bipyramids that share corners with four equivalent Mg(1)O3F3 octahedra, corners with two equivalent Fe(2)O3F2 trigonal bipyramids, corners with two equivalent Fe(4)O3F2 trigonal bipyramids, and edges with two equivalent Fe(1)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 20-61°. In the fourth Fe site, Fe(4) is bonded to one O(2), one O(3), one O(4), one F(2), and one F(4) atom to form distorted FeO3F2 trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Fe(1)O3F2 trigonal bipyramids, corners with two equivalent Fe(3)O3F2 trigonal bipyramids,  an edgeedge with one Mg(1)O3F3 octahedra, and edges with two equivalent Fe(2)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 60°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form a mixture of distorted corner and edge-sharing OMgFe3 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(2), one Fe(3), and one Fe(4) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(4) atom to form a mixture of distorted corner and edge-sharing OMgFe3 tetrahedra. There are four inequivalent F sites. In the first F site, F(1) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the second F site, F(2) is bonded in an L-shaped geometry to one Fe(2) and one Fe(4) atom. In the third F site, F(3) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the fourth F site, F(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(2), and one Fe(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe4(OF)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.724
_cell_length_b   5.492
_cell_length_c   5.307
_cell_angle_alpha   90.609
_cell_angle_beta   90.456
_cell_angle_gamma   85.710
_symmetry_Int_Tables_number   1
_cell_volume   166.344
_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  0.994  1.000  0.518  1.0
  Fe  Fe1  1  0.977  0.103  0.043  1.0
  Fe  Fe2  1  0.261  0.421  0.574  1.0
  Fe  Fe3  1  0.488  0.900  0.950  1.0
  Fe  Fe4  1  0.724  0.575  0.414  1.0
  O  O5  1  0.222  0.142  0.776  1.0
  O  O6  1  0.501  0.624  0.688  1.0
  O  O7  1  0.762  0.862  0.231  1.0
  O  O8  1  0.987  0.336  0.351  1.0
  F  F9  1  0.242  0.887  0.254  1.0
  F  F10  1  0.480  0.367  0.276  1.0
  F  F11  1  0.734  0.107  0.756  1.0
  F  F12  1  0.001  0.678  0.684  1.0
[/CIF]
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The compound described by MgFe4(OF)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one O(3), one O(4), one F(1), one F(3), and one F(4) atom to form MgO3F3 octahedra that share  a cornercorner with one Fe(2)O3F2 trigonal bipyramid,  a cornercorner with one Fe(4)O3F2 trigonal bipyramid, corners with four equivalent Fe(3)O3F2 trigonal bipyramids,  an edgeedge with one Fe(1)O3F2 trigonal bipyramid,  an edgeedge with one Fe(2)O3F2 trigonal bipyramid,  an edgeedge with one Fe(4)O3F2 trigonal bipyramid, and  a faceface with one Fe(1)O3F2 trigonal bipyramid. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(3), one O(4), one F(1), and one F(3) atom to form distorted FeO3F2 trigonal bipyramids that share corners with two equivalent Fe(2)O3F2 trigonal bipyramids, corners with two equivalent Fe(4)O3F2 trigonal bipyramids,  an edgeedge with one Mg(1)O3F3 octahedra, edges with two equivalent Fe(3)O3F2 trigonal bipyramids, and  a faceface with one Mg(1)O3F3 octahedra. In the second Fe site, Fe(2) is bonded to one O(1), one O(2), one O(4), one F(2), and one F(4) atom to form FeO3F2 trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Fe(1)O3F2 trigonal bipyramids, corners with two equivalent Fe(3)O3F2 trigonal bipyramids,  an edgeedge with one Mg(1)O3F3 octahedra, and edges with two equivalent Fe(4)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 63°. In the third Fe site, Fe(3) is bonded to one O(1), one O(2), one O(3), one F(1), and one F(3) atom to form distorted FeO3F2 trigonal bipyramids that share corners with four equivalent Mg(1)O3F3 octahedra, corners with two equivalent Fe(2)O3F2 trigonal bipyramids, corners with two equivalent Fe(4)O3F2 trigonal bipyramids, and edges with two equivalent Fe(1)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 20-61°. In the fourth Fe site, Fe(4) is bonded to one O(2), one O(3), one O(4), one F(2), and one F(4) atom to form distorted FeO3F2 trigonal bipyramids that share  a cornercorner with one Mg(1)O3F3 octahedra, corners with two equivalent Fe(1)O3F2 trigonal bipyramids, corners with two equivalent Fe(3)O3F2 trigonal bipyramids,  an edgeedge with one Mg(1)O3F3 octahedra, and edges with two equivalent Fe(2)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles are 60°. There are four inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(3) atom to form a mixture of distorted corner and edge-sharing OMgFe3 trigonal pyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(2), one Fe(3), and one Fe(4) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Fe(3), and one Fe(4) atom. In the fourth O site, O(4) is bonded to one Mg(1), one Fe(1), one Fe(2), and one Fe(4) atom to form a mixture of distorted corner and edge-sharing OMgFe3 tetrahedra. There are four inequivalent F sites. In the first F site, F(1) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the second F site, F(2) is bonded in an L-shaped geometry to one Fe(2) and one Fe(4) atom. In the third F site, F(3) is bonded in a T-shaped geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the fourth F site, F(4) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(2), and one Fe(4) atom. is represented by the Crystallographic Information File (CIF) [CIF]
data_MgFe4(OF)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.724
_cell_length_b   5.492
_cell_length_c   5.307
_cell_angle_alpha   90.609
_cell_angle_beta   90.456
_cell_angle_gamma   85.710
_symmetry_Int_Tables_number   1
_cell_volume   166.344
_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  0.994  1.000  0.518  1.0
  Fe  Fe1  1  0.977  0.103  0.043  1.0
  Fe  Fe2  1  0.261  0.421  0.574  1.0
  Fe  Fe3  1  0.488  0.900  0.950  1.0
  Fe  Fe4  1  0.724  0.575  0.414  1.0
  O  O5  1  0.222  0.142  0.776  1.0
  O  O6  1  0.501  0.624  0.688  1.0
  O  O7  1  0.762  0.862  0.231  1.0
  O  O8  1  0.987  0.336  0.351  1.0
  F  F9  1  0.242  0.887  0.254  1.0
  F  F10  1  0.480  0.367  0.276  1.0
  F  F11  1  0.734  0.107  0.756  1.0
  F  F12  1  0.001  0.678  0.684  1.0
[/CIF]
.