The material described by MgFe4(OF)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one F(1), one F(3), and one F(4) atom to form distorted MgOF3 tetrahedra that share  a cornercorner with one Fe(1)O3F3 octahedra, corners with two equivalent Fe(4)O3F3 octahedra, corners with two equivalent Fe(3)O3F tetrahedra,  a cornercorner with one Fe(2)O3F2 trigonal bipyramid, and  an edgeedge with one Fe(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 21-51°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(3), one F(1), one F(2), and one F(3) atom to form distorted FeO3F3 octahedra that share  a cornercorner with one Mg(1)OF3 tetrahedra, corners with three equivalent Fe(3)O3F tetrahedra,  a cornercorner with one Fe(2)O3F2 trigonal bipyramid, edges with two equivalent Fe(4)O3F3 octahedra,  an edgeedge with one Mg(1)OF3 tetrahedra, and  an edgeedge with one Fe(2)O3F2 trigonal bipyramid. In the second Fe site, Fe(2) 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 Fe(1)O3F3 octahedra, corners with three equivalent Fe(4)O3F3 octahedra,  a cornercorner with one Mg(1)OF3 tetrahedra, corners with two equivalent Fe(3)O3F tetrahedra,  an edgeedge with one Fe(1)O3F3 octahedra, and  an edgeedge with one Fe(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 22-70°. In the third Fe site, Fe(3) is bonded to one O(1), one O(3), one O(4), and one F(1) atom to form distorted FeO3F tetrahedra that share corners with two equivalent Fe(4)O3F3 octahedra, corners with three equivalent Fe(1)O3F3 octahedra, corners with two equivalent Mg(1)OF3 tetrahedra, and corners with two equivalent Fe(2)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 32-71°. In the fourth Fe site, Fe(4) is bonded to one O(2), one O(3), one O(4), one F(2), one F(3), and one F(4) atom to form FeO3F3 octahedra that share corners with two equivalent Mg(1)OF3 tetrahedra, corners with two equivalent Fe(3)O3F tetrahedra, corners with three equivalent Fe(2)O3F2 trigonal bipyramids, edges with two equivalent Fe(1)O3F3 octahedra, and  an edgeedge with one Fe(2)O3F2 trigonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(3), and one Fe(4) atom. There are four inequivalent F sites. In the first F site, F(1) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the second F site, F(2) is bonded in a T-shaped geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the third F site, F(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one Fe(4) atom. In the fourth F site, F(4) is bonded in a distorted trigonal planar 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   5.289
_cell_length_b   5.136
_cell_length_c   6.460
_cell_angle_alpha   88.385
_cell_angle_beta   90.862
_cell_angle_gamma   101.090
_symmetry_Int_Tables_number   1
_cell_volume   172.105
_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  0.453  0.156  0.877  1.0
  Fe  Fe1  1  0.195  0.488  0.609  1.0
  Fe  Fe2  1  0.171  0.988  0.322  1.0
  Fe  Fe3  1  0.890  0.880  0.840  1.0
  Fe  Fe4  1  0.763  0.524  0.338  1.0
  O  O5  1  0.112  0.238  0.832  1.0
  O  O6  1  0.014  0.297  0.384  1.0
  O  O7  1  0.964  0.736  0.567  1.0
  O  O8  1  0.906  0.762  0.127  1.0
  F  F9  1  0.469  0.791  0.817  1.0
  F  F10  1  0.438  0.727  0.387  1.0
  F  F11  1  0.534  0.315  0.599  1.0
  F  F12  1  0.516  0.237  0.165  1.0
[/CIF]
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The material described by MgFe4(OF)4 crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(1), one F(1), one F(3), and one F(4) atom to form distorted MgOF3 tetrahedra that share  a cornercorner with one Fe(1)O3F3 octahedra, corners with two equivalent Fe(4)O3F3 octahedra, corners with two equivalent Fe(3)O3F tetrahedra,  a cornercorner with one Fe(2)O3F2 trigonal bipyramid, and  an edgeedge with one Fe(1)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 21-51°. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(3), one F(1), one F(2), and one F(3) atom to form distorted FeO3F3 octahedra that share  a cornercorner with one Mg(1)OF3 tetrahedra, corners with three equivalent Fe(3)O3F tetrahedra,  a cornercorner with one Fe(2)O3F2 trigonal bipyramid, edges with two equivalent Fe(4)O3F3 octahedra,  an edgeedge with one Mg(1)OF3 tetrahedra, and  an edgeedge with one Fe(2)O3F2 trigonal bipyramid. In the second Fe site, Fe(2) 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 Fe(1)O3F3 octahedra, corners with three equivalent Fe(4)O3F3 octahedra,  a cornercorner with one Mg(1)OF3 tetrahedra, corners with two equivalent Fe(3)O3F tetrahedra,  an edgeedge with one Fe(1)O3F3 octahedra, and  an edgeedge with one Fe(4)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 22-70°. In the third Fe site, Fe(3) is bonded to one O(1), one O(3), one O(4), and one F(1) atom to form distorted FeO3F tetrahedra that share corners with two equivalent Fe(4)O3F3 octahedra, corners with three equivalent Fe(1)O3F3 octahedra, corners with two equivalent Mg(1)OF3 tetrahedra, and corners with two equivalent Fe(2)O3F2 trigonal bipyramids. The corner-sharing octahedral tilt angles range from 32-71°. In the fourth Fe site, Fe(4) is bonded to one O(2), one O(3), one O(4), one F(2), one F(3), and one F(4) atom to form FeO3F3 octahedra that share corners with two equivalent Mg(1)OF3 tetrahedra, corners with two equivalent Fe(3)O3F tetrahedra, corners with three equivalent Fe(2)O3F2 trigonal bipyramids, edges with two equivalent Fe(1)O3F3 octahedra, and  an edgeedge with one Fe(2)O3F2 trigonal bipyramid. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal non-coplanar geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the second O site, O(2) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the third O site, O(3) is bonded in a distorted rectangular see-saw-like geometry to one Fe(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(2), one Fe(3), and one Fe(4) atom. There are four inequivalent F sites. In the first F site, F(1) is bonded in a 3-coordinate geometry to one Mg(1), one Fe(1), and one Fe(3) atom. In the second F site, F(2) is bonded in a T-shaped geometry to one Fe(1), one Fe(2), and one Fe(4) atom. In the third F site, F(3) is bonded in a distorted T-shaped geometry to one Mg(1), one Fe(1), and one Fe(4) atom. In the fourth F site, F(4) is bonded in a distorted trigonal planar 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   5.289
_cell_length_b   5.136
_cell_length_c   6.460
_cell_angle_alpha   88.385
_cell_angle_beta   90.862
_cell_angle_gamma   101.090
_symmetry_Int_Tables_number   1
_cell_volume   172.105
_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  0.453  0.156  0.877  1.0
  Fe  Fe1  1  0.195  0.488  0.609  1.0
  Fe  Fe2  1  0.171  0.988  0.322  1.0
  Fe  Fe3  1  0.890  0.880  0.840  1.0
  Fe  Fe4  1  0.763  0.524  0.338  1.0
  O  O5  1  0.112  0.238  0.832  1.0
  O  O6  1  0.014  0.297  0.384  1.0
  O  O7  1  0.964  0.736  0.567  1.0
  O  O8  1  0.906  0.762  0.127  1.0
  F  F9  1  0.469  0.791  0.817  1.0
  F  F10  1  0.438  0.727  0.387  1.0
  F  F11  1  0.534  0.315  0.599  1.0
  F  F12  1  0.516  0.237  0.165  1.0
[/CIF]
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