The material described by MgFe4(HO2)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with two equivalent Fe(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 21°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and  an edgeedge with one Fe(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 39-66°. 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  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, edges with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 21°. 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 rectangular see-saw-like geometry to two equivalent Mg(1), one 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 two equivalent Fe(1) and two equivalent Fe(2) atoms to form a mixture of edge and corner-sharing OFe4 trigonal pyramids. In the fourth O site, O(4) is bonded in a see-saw-like geometry to one Mg(1), one Fe(2), and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_MgFe4(HO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.960
_cell_length_b   7.775
_cell_length_c   8.841
_cell_angle_alpha   104.651
_cell_angle_beta   83.045
_cell_angle_gamma   156.628
_symmetry_Int_Tables_number   1
_cell_volume   200.999
_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  0.280  0.755  0.313  1.0
  Fe  Fe2  1  0.720  0.245  0.687  1.0
  Fe  Fe3  1  0.219  0.419  0.545  1.0
  Fe  Fe4  1  0.781  0.581  0.455  1.0
  H  H5  1  0.907  0.689  0.971  1.0
  H  H6  1  0.093  0.311  0.029  1.0
  H  H7  1  0.056  1.000  0.256  1.0
  H  H8  1  0.944  0.000  0.744  1.0
  O  O9  1  0.897  0.551  0.942  1.0
  O  O10  1  0.103  0.449  0.058  1.0
  O  O11  1  0.158  0.109  0.372  1.0
  O  O12  1  0.842  0.891  0.628  1.0
  O  O13  1  0.603  0.902  0.449  1.0
  O  O14  1  0.397  0.098  0.551  1.0
  O  O15  1  0.312  0.694  0.745  1.0
  O  O16  1  0.688  0.306  0.255  1.0
[/CIF]
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The material described by MgFe4(HO2)4 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(4) and four equivalent O(1) atoms to form MgO6 octahedra that share corners with two equivalent Fe(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with four equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 21°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), two equivalent O(3), and two equivalent O(4) atoms to form distorted FeO5 trigonal bipyramids that share corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and  an edgeedge with one Fe(1)O5 trigonal bipyramid. The corner-sharing octahedral tilt angles range from 39-66°. 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  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Fe(1)O5 trigonal bipyramids, edges with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(1)O5 trigonal bipyramids. The corner-sharing octahedral tilt angles are 21°. 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 rectangular see-saw-like geometry to two equivalent Mg(1), one 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 two equivalent Fe(1) and two equivalent Fe(2) atoms to form a mixture of edge and corner-sharing OFe4 trigonal pyramids. In the fourth O site, O(4) is bonded in a see-saw-like geometry to one Mg(1), one Fe(2), and two equivalent Fe(1) atoms. is represented by the CIF file [CIF]
data_MgFe4(HO2)4
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   7.960
_cell_length_b   7.775
_cell_length_c   8.841
_cell_angle_alpha   104.651
_cell_angle_beta   83.045
_cell_angle_gamma   156.628
_symmetry_Int_Tables_number   1
_cell_volume   200.999
_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  0.280  0.755  0.313  1.0
  Fe  Fe2  1  0.720  0.245  0.687  1.0
  Fe  Fe3  1  0.219  0.419  0.545  1.0
  Fe  Fe4  1  0.781  0.581  0.455  1.0
  H  H5  1  0.907  0.689  0.971  1.0
  H  H6  1  0.093  0.311  0.029  1.0
  H  H7  1  0.056  1.000  0.256  1.0
  H  H8  1  0.944  0.000  0.744  1.0
  O  O9  1  0.897  0.551  0.942  1.0
  O  O10  1  0.103  0.449  0.058  1.0
  O  O11  1  0.158  0.109  0.372  1.0
  O  O12  1  0.842  0.891  0.628  1.0
  O  O13  1  0.603  0.902  0.449  1.0
  O  O14  1  0.397  0.098  0.551  1.0
  O  O15  1  0.312  0.694  0.745  1.0
  O  O16  1  0.688  0.306  0.255  1.0
[/CIF]
.