The compound described by MgFe4(HO2)4 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with four equivalent Fe(2)O6 octahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), two equivalent O(4), and three equivalent O(1) atoms to form distorted FeO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-58°. In the second Fe site, Fe(2) is bonded to one O(4), two equivalent O(3), and three equivalent O(2) atoms to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-58°. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(2) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to three equivalent Fe(1) and one H(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Fe(2) and one H(2) atom. In the third O site, O(3) is bonded to one Mg(1), one Fe(1), and two equivalent Fe(2) atoms to form distorted corner-sharing OMgFe3 trigonal pyramids. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Fe(2), and two equivalent Fe(1) atoms. is represented by the CIF card [CIF]
data_MgFe4(HO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.056
_cell_length_b   8.056
_cell_length_c   8.248
_cell_angle_alpha   96.561
_cell_angle_beta   87.582
_cell_angle_gamma   157.852
_symmetry_Int_Tables_number   1
_cell_volume   197.573
_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  0.561  0.061  0.500  1.0
  Fe  Fe1  1  0.308  0.800  0.176  1.0
  Fe  Fe2  1  0.624  0.132  0.824  1.0
  Fe  Fe3  1  0.195  0.383  0.489  1.0
  Fe  Fe4  1  0.894  0.705  0.511  1.0
  H  H5  1  0.044  0.798  0.929  1.0
  H  H6  1  0.869  0.115  0.071  1.0
  H  H7  1  0.219  0.130  0.258  1.0
  H  H8  1  0.872  0.961  0.742  1.0
  O  O9  1  0.112  0.750  0.959  1.0
  O  O10  1  0.791  0.153  0.041  1.0
  O  O11  1  0.265  0.201  0.378  1.0
  O  O12  1  0.823  0.888  0.622  1.0
  O  O13  1  0.589  0.860  0.366  1.0
  O  O14  1  0.494  0.223  0.634  1.0
  O  O15  1  0.170  0.569  0.648  1.0
  O  O16  1  0.921  0.522  0.352  1.0
[/CIF]
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The compound described by MgFe4(HO2)4 crystallizes in the monoclinic C2 space group. Mg(1) is bonded to two equivalent O(3) and four equivalent O(4) atoms to form MgO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with four equivalent Fe(2)O6 octahedra, and faces with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-47°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(3), two equivalent O(4), and three equivalent O(1) atoms to form distorted FeO6 octahedra that share corners with two equivalent Mg(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with four equivalent Fe(1)O6 octahedra, and  a faceface with one Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 42-58°. In the second Fe site, Fe(2) is bonded to one O(4), two equivalent O(3), and three equivalent O(2) atoms to form FeO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-58°. There are two inequivalent H sites. In the first H site, H(1) is bonded in a single-bond geometry to one O(1) atom. In the second H site, H(2) is bonded in a single-bond geometry to one O(2) atom. There are four inequivalent O sites. In the first O site, O(1) is bonded in a distorted single-bond geometry to three equivalent Fe(1) and one H(1) atom. In the second O site, O(2) is bonded in a distorted single-bond geometry to three equivalent Fe(2) and one H(2) atom. In the third O site, O(3) is bonded to one Mg(1), one Fe(1), and two equivalent Fe(2) atoms to form distorted corner-sharing OMgFe3 trigonal pyramids. In the fourth O site, O(4) is bonded in a 5-coordinate geometry to two equivalent Mg(1), one Fe(2), and two equivalent Fe(1) atoms. is represented by the CIF card [CIF]
data_MgFe4(HO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   8.056
_cell_length_b   8.056
_cell_length_c   8.248
_cell_angle_alpha   96.561
_cell_angle_beta   87.582
_cell_angle_gamma   157.852
_symmetry_Int_Tables_number   1
_cell_volume   197.573
_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  0.561  0.061  0.500  1.0
  Fe  Fe1  1  0.308  0.800  0.176  1.0
  Fe  Fe2  1  0.624  0.132  0.824  1.0
  Fe  Fe3  1  0.195  0.383  0.489  1.0
  Fe  Fe4  1  0.894  0.705  0.511  1.0
  H  H5  1  0.044  0.798  0.929  1.0
  H  H6  1  0.869  0.115  0.071  1.0
  H  H7  1  0.219  0.130  0.258  1.0
  H  H8  1  0.872  0.961  0.742  1.0
  O  O9  1  0.112  0.750  0.959  1.0
  O  O10  1  0.791  0.153  0.041  1.0
  O  O11  1  0.265  0.201  0.378  1.0
  O  O12  1  0.823  0.888  0.622  1.0
  O  O13  1  0.589  0.860  0.366  1.0
  O  O14  1  0.494  0.223  0.634  1.0
  O  O15  1  0.170  0.569  0.648  1.0
  O  O16  1  0.921  0.522  0.352  1.0
[/CIF]
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