The material described by MgFe4(OF)4 crystallizes in the monoclinic P2/m space group. Mg(1) is bonded to four equivalent O(1) and two equivalent F(2) atoms to form MgO4F2 octahedra that share corners with four equivalent Fe(1)O4F2 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, edges with four equivalent Fe(3)O3F3 octahedra, and faces with two equivalent Fe(1)O4F2 octahedra. The corner-sharing octahedral tilt angles are 40°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent O(1) and two equivalent F(2) atoms to form distorted FeO4F2 octahedra that share corners with four equivalent Mg(1)O4F2 octahedra, corners with eight equivalent Fe(3)O3F3 octahedra, edges with two equivalent Fe(1)O4F2 octahedra, and faces with two equivalent Mg(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 40-58°. In the second Fe site, Fe(2) is bonded to two equivalent O(2) and four equivalent F(1) atoms to form FeO2F4 octahedra that share corners with eight equivalent Fe(3)O3F3 octahedra and edges with two equivalent Fe(2)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 45-55°. In the third Fe site, Fe(3) is bonded to one O(1), two equivalent O(2), one F(1), and two equivalent F(2) atoms to form distorted FeO3F3 octahedra that share corners with four equivalent Fe(2)O2F4 octahedra, corners with four equivalent Fe(1)O4F2 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and edges with two equivalent Fe(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 44-58°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Fe(3), and two equivalent Fe(1) atoms to form a mixture of distorted edge and corner-sharing OMg2Fe3 trigonal bipyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Fe(3) and two equivalent Fe(2) atoms. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), and two equivalent Fe(3) atoms. is represented by the CIF file [CIF]
data_MgFe4(OF)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.142
_cell_length_b   9.726
_cell_length_c   3.077
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   85.985
_symmetry_Int_Tables_number   1
_cell_volume   153.512
_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  0.500  0.000  0.000  1.0
  Fe  Fe1  1  0.000  0.000  0.000  1.0
  Fe  Fe2  1  0.000  0.500  0.000  1.0
  Fe  Fe3  1  0.575  0.276  0.500  1.0
  Fe  Fe4  1  0.425  0.724  0.500  1.0
  O  O5  1  0.262  0.926  0.500  1.0
  O  O6  1  0.259  0.656  0.000  1.0
  O  O7  1  0.741  0.344  0.000  1.0
  O  O8  1  0.738  0.074  0.500  1.0
  F  F9  1  0.247  0.403  0.500  1.0
  F  F10  1  0.317  0.181  0.000  1.0
  F  F11  1  0.683  0.819  0.000  1.0
  F  F12  1  0.753  0.597  0.500  1.0
[/CIF]
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The material described by MgFe4(OF)4 crystallizes in the monoclinic P2/m space group. Mg(1) is bonded to four equivalent O(1) and two equivalent F(2) atoms to form MgO4F2 octahedra that share corners with four equivalent Fe(1)O4F2 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, edges with four equivalent Fe(3)O3F3 octahedra, and faces with two equivalent Fe(1)O4F2 octahedra. The corner-sharing octahedral tilt angles are 40°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to four equivalent O(1) and two equivalent F(2) atoms to form distorted FeO4F2 octahedra that share corners with four equivalent Mg(1)O4F2 octahedra, corners with eight equivalent Fe(3)O3F3 octahedra, edges with two equivalent Fe(1)O4F2 octahedra, and faces with two equivalent Mg(1)O4F2 octahedra. The corner-sharing octahedral tilt angles range from 40-58°. In the second Fe site, Fe(2) is bonded to two equivalent O(2) and four equivalent F(1) atoms to form FeO2F4 octahedra that share corners with eight equivalent Fe(3)O3F3 octahedra and edges with two equivalent Fe(2)O2F4 octahedra. The corner-sharing octahedral tilt angles range from 45-55°. In the third Fe site, Fe(3) is bonded to one O(1), two equivalent O(2), one F(1), and two equivalent F(2) atoms to form distorted FeO3F3 octahedra that share corners with four equivalent Fe(2)O2F4 octahedra, corners with four equivalent Fe(1)O4F2 octahedra, edges with two equivalent Mg(1)O4F2 octahedra, and edges with two equivalent Fe(3)O3F3 octahedra. The corner-sharing octahedral tilt angles range from 44-58°. There are two inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Fe(3), and two equivalent Fe(1) atoms to form a mixture of distorted edge and corner-sharing OMg2Fe3 trigonal bipyramids. In the second O site, O(2) is bonded in a trigonal planar geometry to one Fe(2) and two equivalent Fe(3) atoms. There are two inequivalent F sites. In the first F site, F(1) is bonded in a distorted T-shaped geometry to one Fe(3) and two equivalent Fe(2) atoms. In the second F site, F(2) is bonded in a 4-coordinate geometry to one Mg(1), one Fe(1), and two equivalent Fe(3) atoms. is represented by the CIF file [CIF]
data_MgFe4(OF)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.142
_cell_length_b   9.726
_cell_length_c   3.077
_cell_angle_alpha   90.000
_cell_angle_beta   90.000
_cell_angle_gamma   85.985
_symmetry_Int_Tables_number   1
_cell_volume   153.512
_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  0.500  0.000  0.000  1.0
  Fe  Fe1  1  0.000  0.000  0.000  1.0
  Fe  Fe2  1  0.000  0.500  0.000  1.0
  Fe  Fe3  1  0.575  0.276  0.500  1.0
  Fe  Fe4  1  0.425  0.724  0.500  1.0
  O  O5  1  0.262  0.926  0.500  1.0
  O  O6  1  0.259  0.656  0.000  1.0
  O  O7  1  0.741  0.344  0.000  1.0
  O  O8  1  0.738  0.074  0.500  1.0
  F  F9  1  0.247  0.403  0.500  1.0
  F  F10  1  0.317  0.181  0.000  1.0
  F  F11  1  0.683  0.819  0.000  1.0
  F  F12  1  0.753  0.597  0.500  1.0
[/CIF]
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