The crystal structure described by MgFe(CoO3)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(6) atoms to form MgO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra, corners with four equivalent Co(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-22°. Fe(1) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form FeO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles are 22°. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(6) atoms to form CoO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-12°. In the second Co site, Co(2) is bonded to one O(2), one O(6), two equivalent O(3), and two equivalent O(5) atoms to form CoO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are six inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Fe(1), and two equivalent Co(1) atoms to form OMg2FeCo2 square pyramids that share corners with four equivalent O(6)Mg2Co3 square pyramids, corners with three equivalent O(5)MgFeCo2 trigonal pyramids, edges with two equivalent O(6)Mg2Co3 square pyramids, and edges with two equivalent O(1)Mg2FeCo2 square pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), two equivalent Fe(1), and one Co(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Co(1) and two equivalent Co(2) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Fe(1) and one Co(1) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(1), and two equivalent Co(2) atoms to form OMgFeCo2 trigonal pyramids that share corners with three equivalent O(1)Mg2FeCo2 square pyramids, corners with two equivalent O(5)MgFeCo2 trigonal pyramids, and edges with two equivalent O(6)Mg2Co3 square pyramids. In the sixth O site, O(6) is bonded to two equivalent Mg(1), one Co(2), and two equivalent Co(1) atoms to form OMg2Co3 square pyramids that share corners with four equivalent O(1)Mg2FeCo2 square pyramids, edges with two equivalent O(6)Mg2Co3 square pyramids, edges with two equivalent O(1)Mg2FeCo2 square pyramids, and edges with two equivalent O(5)MgFeCo2 trigonal pyramids. is represented by the CIF file [CIF]
data_MgFe(CoO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.471
_cell_length_b   2.904
_cell_length_c   5.743
_cell_angle_alpha   89.966
_cell_angle_beta   103.193
_cell_angle_gamma   77.059
_symmetry_Int_Tables_number   1
_cell_volume   102.259
_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  0.012  0.994  0.511  1.0
  Fe  Fe1  1  0.362  0.320  0.298  1.0
  Co  Co2  1  0.991  0.005  0.007  1.0
  Co  Co3  1  0.655  0.673  0.687  1.0
  O  O4  1  0.014  0.493  0.243  1.0
  O  O5  1  0.350  0.825  0.545  1.0
  O  O6  1  0.680  0.160  0.899  1.0
  O  O7  1  0.299  0.851  0.069  1.0
  O  O8  1  0.677  0.162  0.468  1.0
  O  O9  1  0.969  0.516  0.773  1.0
[/CIF]
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The crystal structure described by MgFe(CoO3)2 crystallizes in the monoclinic Cm space group. Mg(1) is bonded to one O(2), one O(5), two equivalent O(1), and two equivalent O(6) atoms to form MgO6 octahedra that share  a cornercorner with one Fe(1)O6 octahedra,  a cornercorner with one Co(2)O6 octahedra, corners with four equivalent Co(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-22°. Fe(1) is bonded to one O(1), one O(5), two equivalent O(2), and two equivalent O(4) atoms to form FeO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles are 22°. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(3), one O(4), two equivalent O(1), and two equivalent O(6) atoms to form CoO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-12°. In the second Co site, Co(2) is bonded to one O(2), one O(6), two equivalent O(3), and two equivalent O(5) atoms to form CoO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles are 19°. There are six inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Mg(1), one Fe(1), and two equivalent Co(1) atoms to form OMg2FeCo2 square pyramids that share corners with four equivalent O(6)Mg2Co3 square pyramids, corners with three equivalent O(5)MgFeCo2 trigonal pyramids, edges with two equivalent O(6)Mg2Co3 square pyramids, and edges with two equivalent O(1)Mg2FeCo2 square pyramids. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), two equivalent Fe(1), and one Co(2) atom. In the third O site, O(3) is bonded in a distorted trigonal non-coplanar geometry to one Co(1) and two equivalent Co(2) atoms. In the fourth O site, O(4) is bonded in a distorted trigonal non-coplanar geometry to two equivalent Fe(1) and one Co(1) atom. In the fifth O site, O(5) is bonded to one Mg(1), one Fe(1), and two equivalent Co(2) atoms to form OMgFeCo2 trigonal pyramids that share corners with three equivalent O(1)Mg2FeCo2 square pyramids, corners with two equivalent O(5)MgFeCo2 trigonal pyramids, and edges with two equivalent O(6)Mg2Co3 square pyramids. In the sixth O site, O(6) is bonded to two equivalent Mg(1), one Co(2), and two equivalent Co(1) atoms to form OMg2Co3 square pyramids that share corners with four equivalent O(1)Mg2FeCo2 square pyramids, edges with two equivalent O(6)Mg2Co3 square pyramids, edges with two equivalent O(1)Mg2FeCo2 square pyramids, and edges with two equivalent O(5)MgFeCo2 trigonal pyramids. is represented by the CIF file [CIF]
data_MgFe(CoO3)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   6.471
_cell_length_b   2.904
_cell_length_c   5.743
_cell_angle_alpha   89.966
_cell_angle_beta   103.193
_cell_angle_gamma   77.059
_symmetry_Int_Tables_number   1
_cell_volume   102.259
_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  0.012  0.994  0.511  1.0
  Fe  Fe1  1  0.362  0.320  0.298  1.0
  Co  Co2  1  0.991  0.005  0.007  1.0
  Co  Co3  1  0.655  0.673  0.687  1.0
  O  O4  1  0.014  0.493  0.243  1.0
  O  O5  1  0.350  0.825  0.545  1.0
  O  O6  1  0.680  0.160  0.899  1.0
  O  O7  1  0.299  0.851  0.069  1.0
  O  O8  1  0.677  0.162  0.468  1.0
  O  O9  1  0.969  0.516  0.773  1.0
[/CIF]
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