The material described by MgFe2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(16), one O(3), and one O(4) atom to form MgO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Fe(10)O6 octahedra,  a cornercorner with one Fe(8)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, and corners with three equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-60°. In the second Mg site, Mg(2) is bonded to one O(10), one O(11), one O(12), one O(5), one O(6), and one O(7) atom to form MgO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(9)O4 tetrahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra,  an edgeedge with one Fe(6)O6 octahedra, and  an edgeedge with one Fe(7)O6 octahedra. In the third Mg site, Mg(3) is bonded to one O(14), one O(16), one O(18), one O(22), one O(23), and one O(24) atom to form MgO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(11)O4 tetrahedra, corners with two equivalent Fe(12)O4 tetrahedra, corners with two equivalent Fe(5)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Fe(10)O6 octahedra, and edges with two equivalent Fe(8)O6 octahedra. In the fourth Mg site, Mg(4) is bonded to one O(1), one O(11), one O(2), one O(3), one O(7), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Fe(12)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Fe(9)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. In the fifth Mg site, Mg(5) is bonded to one O(13), one O(14), one O(15), one O(18), one O(19), and one O(20) atom to form MgO6 octahedra that share corners with three equivalent Fe(11)O4 tetrahedra, corners with three equivalent Fe(5)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Fe(10)O6 octahedra,  an edgeedge with one Fe(6)O6 octahedra,  an edgeedge with one Fe(7)O6 octahedra, and  an edgeedge with one Fe(8)O6 octahedra. In the sixth Mg site, Mg(6) is bonded to one O(10), one O(15), one O(17), one O(20), one O(6), and one O(8) atom to form MgO6 octahedra that share  a cornercorner with one Fe(5)O4 tetrahedra,  a cornercorner with one Fe(9)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(11)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Fe(6)O6 octahedra, and edges with two equivalent Fe(7)O6 octahedra. There are twelve inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(10), one O(12), one O(2), and one O(6) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Mg(6)O6 octahedra, corners with two equivalent Fe(6)O6 octahedra, corners with two equivalent Fe(7)O6 octahedra, and corners with three equivalent Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-59°. In the second Fe site, Fe(2) is bonded to one O(1), one O(11), one O(2), one O(4), one O(5), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Fe(12)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Fe(9)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. In the third Fe site, Fe(3) is bonded to one O(1), one O(21), one O(22), one O(24), one O(3), and one O(4) atom to form FeO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Fe(12)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Fe(10)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and  an edgeedge with one Fe(8)O6 octahedra. In the fourth Fe site, Fe(4) is bonded to one O(2), one O(3), one O(4), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Fe(12)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Fe(9)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. In the fifth Fe site, Fe(5) is bonded to one O(14), one O(18), one O(19), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(6)O6 octahedra,  a cornercorner with one Fe(6)O6 octahedra,  a cornercorner with one Fe(7)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Fe(10)O6 octahedra, corners with two equivalent Fe(8)O6 octahedra, and corners with three equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-59°. In the sixth Fe site, Fe(6) is bonded to one O(12), one O(13), one O(17), one O(20), one O(6), and one O(8) atom to form FeO6 octahedra that share  a cornercorner with one Fe(5)O4 tetrahedra,  a cornercorner with one Fe(9)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(11)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, and edges with two equivalent Fe(7)O6 octahedra. In the seventh Fe site, Fe(7) is bonded to one O(10), one O(12), one O(13), one O(15), one O(17), and one O(8) atom to form FeO6 octahedra that share  a cornercorner with one Fe(5)O4 tetrahedra,  a cornercorner with one Fe(9)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(11)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, and edges with two equivalent Fe(6)O6 octahedra. In the eighth Fe site, Fe(8) is bonded to one O(14), one O(16), one O(19), one O(21), one O(23), and one O(24) atom to form FeO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(11)O4 tetrahedra, corners with two equivalent Fe(12)O4 tetrahedra, corners with two equivalent Fe(5)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, and edges with two equivalent Fe(10)O6 octahedra. In the ninth Fe site, Fe(9) is bonded to one O(11), one O(17), one O(5), and one O(7) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(6)O6 octahedra,  a cornercorner with one Fe(6)O6 octahedra,  a cornercorner with one Fe(7)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, and corners with three equivalent Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-58°. In the tenth Fe site, Fe(10) is bonded to one O(16), one O(18), one O(19), one O(21), one O(22), and one O(23) atom to form FeO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(11)O4 tetrahedra, corners with two equivalent Fe(12)O4 tetrahedra, corners with two equivalent Fe(5)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, and edges with two equivalent Fe(8)O6 octahedra. In the eleventh Fe site, Fe(11) is bonded to one O(13), one O(15), one O(20), and one O(23) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Fe(10)O6 octahedra,  a cornercorner with one Fe(8)O6 octahedra, corners with two equivalent Mg(6)O6 octahedra, corners with two equivalent Fe(6)O6 octahedra, corners with two equivalent Fe(7)O6 octahedra, and corners with three equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-59°. In the twelfth Fe site, Fe(12) is bonded to one O(21), one O(22), one O(24), and one O(9) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Fe(10)O6 octahedra, corners with two equivalent Fe(8)O6 octahedra, and corners with three equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-60°. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(4), one Fe(2), and one Fe(3) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(4), one Fe(1), one Fe(2), and one Fe(4) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(4), one Fe(3), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Fe(2), one Fe(4), and one Fe(9) atom. In the sixth O site, O(6) is bonded in a distorted trigonal pyramidal geometry to one Mg(2), one Mg(6), one Fe(1), and one Fe(6) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Mg(4), one Fe(4), and one Fe(9) atom. In the eighth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Fe(5), one Fe(6), and one Fe(7) atom. In the ninth O site, O(9) is bonded in a distorted trigonal pyramidal geometry to one Mg(4), one Fe(12), one Fe(2), and one Fe(4) atom. In the tenth O site, O(10) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Mg(6), one Fe(1), and one Fe(7) atom. In the eleventh O site, O(11) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Mg(4), one Fe(2), and one Fe(9) atom. In the twelfth O site, O(12) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Fe(1), one Fe(6), and one Fe(7) atom. In the thirteenth O site, O(13) is bonded in a rectangular see-saw-like geometry to one Mg(5), one Fe(11), one Fe(6), and one Fe(7) atom. In the fourteenth O site, O(14) is bonded in a rectangular see-saw-like geometry to one Mg(3), one Mg(5), one Fe(5), and one Fe(8) atom. In the fifteenth O site, O(15) is bonded in a rectangular see-saw-like geometry to one Mg(5), one Mg(6), one Fe(11), and one Fe(7) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal pyramidal geometry to one Mg(1), one Mg(3), one Fe(10), and one Fe(8) atom. In the seventeenth O site, O(17) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Fe(6), one Fe(7), and one Fe(9) atom. In the eighteenth O site, O(18) is bonded in a distorted rectangular see-saw-like geometry to one Mg(3), one Mg(5), one Fe(10), and one Fe(5) atom. In the nineteenth O site, O(19) is bonded in a rectangular see-saw-like geometry to one Mg(5), one Fe(10), one Fe(5), and one Fe(8) atom. In the twentieth O site, O(20) is bonded in a distorted rectangular see-saw-like geometry to one Mg(5), one Mg(6), one Fe(11), and one Fe(6) atom. In the twenty-first O site, O(21) is bonded in a rectangular see-saw-like geometry to one Fe(10), one Fe(12), one Fe(3), and one Fe(8) atom. In the twenty-second O site, O(22) is bonded in a rectangular see-saw-like geometry to one Mg(3), one Fe(10), one Fe(12), and one Fe(3) atom. In the twenty-third O site, O(23) is bonded in a distorted rectangular see-saw-like geometry to one Mg(3), one Fe(10), one Fe(11), and one Fe(8) atom. In the twenty-fourth O site, O(24) is bonded in a rectangular see-saw-like geometry to one Mg(3), one Fe(12), one Fe(3), and one Fe(8) atom. is represented by the CIF card [CIF]
data_Mg(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.988
_cell_length_b   6.001
_cell_length_c   14.642
_cell_angle_alpha   90.393
_cell_angle_beta   89.930
_cell_angle_gamma   119.738
_symmetry_Int_Tables_number   1
_cell_volume   456.797
_cell_formula_units_Z   6
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  0.838  0.663  0.959  1.0
  Mg  Mg1  1  0.164  0.330  0.668  1.0
  Mg  Mg2  1  0.667  0.833  0.166  1.0
  Mg  Mg3  1  0.335  0.165  0.834  1.0
  Mg  Mg4  1  0.836  0.670  0.333  1.0
  Mg  Mg5  1  0.000  0.500  0.500  1.0
  Fe  Fe6  1  0.502  0.993  0.621  1.0
  Fe  Fe7  1  0.830  0.165  0.834  1.0
  Fe  Fe8  1  0.500  0.999  0.997  1.0
  Fe  Fe9  1  0.336  0.670  0.834  1.0
  Fe  Fe10  1  0.172  0.331  0.290  1.0
  Fe  Fe11  1  0.501  0.501  0.501  1.0
  Fe  Fe12  1  1.000  1.000  0.500  1.0
  Fe  Fe13  1  0.164  0.833  0.166  1.0
  Fe  Fe14  1  0.828  0.669  0.711  1.0
  Fe  Fe15  1  0.668  0.338  0.165  1.0
  Fe  Fe16  1  0.498  0.007  0.377  1.0
  Fe  Fe17  1  0.163  0.338  0.040  1.0
  O  O18  1  0.656  0.297  0.917  1.0
  O  O19  1  0.502  0.998  0.754  1.0
  O  O20  1  0.203  0.845  0.916  1.0
  O  O21  1  0.653  0.848  0.916  1.0
  O  O22  1  0.003  0.493  0.756  1.0
  O  O23  1  0.326  0.645  0.581  1.0
  O  O24  1  0.483  0.497  0.756  1.0
  O  O25  1  0.177  0.343  0.422  1.0
  O  O26  1  0.166  0.337  0.910  1.0
  O  O27  1  0.851  0.162  0.578  1.0
  O  O28  1  1.000  0.015  0.755  1.0
  O  O29  1  0.320  0.168  0.578  1.0
  O  O30  1  0.680  0.832  0.422  1.0
  O  O31  1  0.001  0.988  0.246  1.0
  O  O32  1  0.150  0.838  0.422  1.0
  O  O33  1  0.837  0.661  0.095  1.0
  O  O34  1  0.822  0.658  0.580  1.0
  O  O35  1  0.518  0.506  0.246  1.0
  O  O36  1  0.999  0.509  0.245  1.0
  O  O37  1  0.673  0.354  0.419  1.0
  O  O38  1  0.341  0.154  0.083  1.0
  O  O39  1  0.806  0.156  0.082  1.0
  O  O40  1  0.495  0.003  0.243  1.0
  O  O41  1  0.339  0.690  0.082  1.0
[/CIF]
.
The material described by MgFe2O4 is Spinel-like structured and crystallizes in the triclinic P1 space group. There are six inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(16), one O(3), and one O(4) atom to form MgO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Fe(10)O6 octahedra,  a cornercorner with one Fe(8)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, and corners with three equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-60°. In the second Mg site, Mg(2) is bonded to one O(10), one O(11), one O(12), one O(5), one O(6), and one O(7) atom to form MgO6 octahedra that share corners with three equivalent Fe(1)O4 tetrahedra, corners with three equivalent Fe(9)O4 tetrahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra,  an edgeedge with one Fe(6)O6 octahedra, and  an edgeedge with one Fe(7)O6 octahedra. In the third Mg site, Mg(3) is bonded to one O(14), one O(16), one O(18), one O(22), one O(23), and one O(24) atom to form MgO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(11)O4 tetrahedra, corners with two equivalent Fe(12)O4 tetrahedra, corners with two equivalent Fe(5)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Fe(10)O6 octahedra, and edges with two equivalent Fe(8)O6 octahedra. In the fourth Mg site, Mg(4) is bonded to one O(1), one O(11), one O(2), one O(3), one O(7), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Fe(12)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Fe(9)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. In the fifth Mg site, Mg(5) is bonded to one O(13), one O(14), one O(15), one O(18), one O(19), and one O(20) atom to form MgO6 octahedra that share corners with three equivalent Fe(11)O4 tetrahedra, corners with three equivalent Fe(5)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Fe(10)O6 octahedra,  an edgeedge with one Fe(6)O6 octahedra,  an edgeedge with one Fe(7)O6 octahedra, and  an edgeedge with one Fe(8)O6 octahedra. In the sixth Mg site, Mg(6) is bonded to one O(10), one O(15), one O(17), one O(20), one O(6), and one O(8) atom to form MgO6 octahedra that share  a cornercorner with one Fe(5)O4 tetrahedra,  a cornercorner with one Fe(9)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(11)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Fe(6)O6 octahedra, and edges with two equivalent Fe(7)O6 octahedra. There are twelve inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(10), one O(12), one O(2), and one O(6) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Mg(6)O6 octahedra, corners with two equivalent Fe(6)O6 octahedra, corners with two equivalent Fe(7)O6 octahedra, and corners with three equivalent Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-59°. In the second Fe site, Fe(2) is bonded to one O(1), one O(11), one O(2), one O(4), one O(5), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Fe(12)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Fe(9)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, and edges with two equivalent Fe(4)O6 octahedra. In the third Fe site, Fe(3) is bonded to one O(1), one O(21), one O(22), one O(24), one O(3), and one O(4) atom to form FeO6 octahedra that share corners with three equivalent Mg(1)O4 tetrahedra, corners with three equivalent Fe(12)O4 tetrahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Fe(10)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and  an edgeedge with one Fe(8)O6 octahedra. In the fourth Fe site, Fe(4) is bonded to one O(2), one O(3), one O(4), one O(5), one O(7), and one O(9) atom to form FeO6 octahedra that share  a cornercorner with one Fe(1)O4 tetrahedra,  a cornercorner with one Fe(12)O4 tetrahedra, corners with two equivalent Mg(1)O4 tetrahedra, corners with two equivalent Fe(9)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. In the fifth Fe site, Fe(5) is bonded to one O(14), one O(18), one O(19), and one O(8) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(6)O6 octahedra,  a cornercorner with one Fe(6)O6 octahedra,  a cornercorner with one Fe(7)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Fe(10)O6 octahedra, corners with two equivalent Fe(8)O6 octahedra, and corners with three equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-59°. In the sixth Fe site, Fe(6) is bonded to one O(12), one O(13), one O(17), one O(20), one O(6), and one O(8) atom to form FeO6 octahedra that share  a cornercorner with one Fe(5)O4 tetrahedra,  a cornercorner with one Fe(9)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(11)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, and edges with two equivalent Fe(7)O6 octahedra. In the seventh Fe site, Fe(7) is bonded to one O(10), one O(12), one O(13), one O(15), one O(17), and one O(8) atom to form FeO6 octahedra that share  a cornercorner with one Fe(5)O4 tetrahedra,  a cornercorner with one Fe(9)O4 tetrahedra, corners with two equivalent Fe(1)O4 tetrahedra, corners with two equivalent Fe(11)O4 tetrahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, and edges with two equivalent Fe(6)O6 octahedra. In the eighth Fe site, Fe(8) is bonded to one O(14), one O(16), one O(19), one O(21), one O(23), and one O(24) atom to form FeO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(11)O4 tetrahedra, corners with two equivalent Fe(12)O4 tetrahedra, corners with two equivalent Fe(5)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, and edges with two equivalent Fe(10)O6 octahedra. In the ninth Fe site, Fe(9) is bonded to one O(11), one O(17), one O(5), and one O(7) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(6)O6 octahedra,  a cornercorner with one Fe(6)O6 octahedra,  a cornercorner with one Fe(7)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(4)O6 octahedra, and corners with three equivalent Mg(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 54-58°. In the tenth Fe site, Fe(10) is bonded to one O(16), one O(18), one O(19), one O(21), one O(22), and one O(23) atom to form FeO6 octahedra that share  a cornercorner with one Mg(1)O4 tetrahedra,  a cornercorner with one Fe(11)O4 tetrahedra, corners with two equivalent Fe(12)O4 tetrahedra, corners with two equivalent Fe(5)O4 tetrahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, and edges with two equivalent Fe(8)O6 octahedra. In the eleventh Fe site, Fe(11) is bonded to one O(13), one O(15), one O(20), and one O(23) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(3)O6 octahedra,  a cornercorner with one Fe(10)O6 octahedra,  a cornercorner with one Fe(8)O6 octahedra, corners with two equivalent Mg(6)O6 octahedra, corners with two equivalent Fe(6)O6 octahedra, corners with two equivalent Fe(7)O6 octahedra, and corners with three equivalent Mg(5)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-59°. In the twelfth Fe site, Fe(12) is bonded to one O(21), one O(22), one O(24), and one O(9) atom to form FeO4 tetrahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Fe(2)O6 octahedra,  a cornercorner with one Fe(4)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra, corners with two equivalent Fe(10)O6 octahedra, corners with two equivalent Fe(8)O6 octahedra, and corners with three equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-60°. There are twenty-four inequivalent O sites. In the first O site, O(1) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(4), one Fe(2), and one Fe(3) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(4), one Fe(1), one Fe(2), and one Fe(4) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Mg(4), one Fe(3), and one Fe(4) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Fe(3), and one Fe(4) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Fe(2), one Fe(4), and one Fe(9) atom. In the sixth O site, O(6) is bonded in a distorted trigonal pyramidal geometry to one Mg(2), one Mg(6), one Fe(1), and one Fe(6) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Mg(4), one Fe(4), and one Fe(9) atom. In the eighth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Fe(5), one Fe(6), and one Fe(7) atom. In the ninth O site, O(9) is bonded in a distorted trigonal pyramidal geometry to one Mg(4), one Fe(12), one Fe(2), and one Fe(4) atom. In the tenth O site, O(10) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Mg(6), one Fe(1), and one Fe(7) atom. In the eleventh O site, O(11) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Mg(4), one Fe(2), and one Fe(9) atom. In the twelfth O site, O(12) is bonded in a rectangular see-saw-like geometry to one Mg(2), one Fe(1), one Fe(6), and one Fe(7) atom. In the thirteenth O site, O(13) is bonded in a rectangular see-saw-like geometry to one Mg(5), one Fe(11), one Fe(6), and one Fe(7) atom. In the fourteenth O site, O(14) is bonded in a rectangular see-saw-like geometry to one Mg(3), one Mg(5), one Fe(5), and one Fe(8) atom. In the fifteenth O site, O(15) is bonded in a rectangular see-saw-like geometry to one Mg(5), one Mg(6), one Fe(11), and one Fe(7) atom. In the sixteenth O site, O(16) is bonded in a distorted trigonal pyramidal geometry to one Mg(1), one Mg(3), one Fe(10), and one Fe(8) atom. In the seventeenth O site, O(17) is bonded in a rectangular see-saw-like geometry to one Mg(6), one Fe(6), one Fe(7), and one Fe(9) atom. In the eighteenth O site, O(18) is bonded in a distorted rectangular see-saw-like geometry to one Mg(3), one Mg(5), one Fe(10), and one Fe(5) atom. In the nineteenth O site, O(19) is bonded in a rectangular see-saw-like geometry to one Mg(5), one Fe(10), one Fe(5), and one Fe(8) atom. In the twentieth O site, O(20) is bonded in a distorted rectangular see-saw-like geometry to one Mg(5), one Mg(6), one Fe(11), and one Fe(6) atom. In the twenty-first O site, O(21) is bonded in a rectangular see-saw-like geometry to one Fe(10), one Fe(12), one Fe(3), and one Fe(8) atom. In the twenty-second O site, O(22) is bonded in a rectangular see-saw-like geometry to one Mg(3), one Fe(10), one Fe(12), and one Fe(3) atom. In the twenty-third O site, O(23) is bonded in a distorted rectangular see-saw-like geometry to one Mg(3), one Fe(10), one Fe(11), and one Fe(8) atom. In the twenty-fourth O site, O(24) is bonded in a rectangular see-saw-like geometry to one Mg(3), one Fe(12), one Fe(3), and one Fe(8) atom. is represented by the CIF card [CIF]
data_Mg(FeO2)2
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   5.988
_cell_length_b   6.001
_cell_length_c   14.642
_cell_angle_alpha   90.393
_cell_angle_beta   89.930
_cell_angle_gamma   119.738
_symmetry_Int_Tables_number   1
_cell_volume   456.797
_cell_formula_units_Z   6
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  0.838  0.663  0.959  1.0
  Mg  Mg1  1  0.164  0.330  0.668  1.0
  Mg  Mg2  1  0.667  0.833  0.166  1.0
  Mg  Mg3  1  0.335  0.165  0.834  1.0
  Mg  Mg4  1  0.836  0.670  0.333  1.0
  Mg  Mg5  1  0.000  0.500  0.500  1.0
  Fe  Fe6  1  0.502  0.993  0.621  1.0
  Fe  Fe7  1  0.830  0.165  0.834  1.0
  Fe  Fe8  1  0.500  0.999  0.997  1.0
  Fe  Fe9  1  0.336  0.670  0.834  1.0
  Fe  Fe10  1  0.172  0.331  0.290  1.0
  Fe  Fe11  1  0.501  0.501  0.501  1.0
  Fe  Fe12  1  1.000  1.000  0.500  1.0
  Fe  Fe13  1  0.164  0.833  0.166  1.0
  Fe  Fe14  1  0.828  0.669  0.711  1.0
  Fe  Fe15  1  0.668  0.338  0.165  1.0
  Fe  Fe16  1  0.498  0.007  0.377  1.0
  Fe  Fe17  1  0.163  0.338  0.040  1.0
  O  O18  1  0.656  0.297  0.917  1.0
  O  O19  1  0.502  0.998  0.754  1.0
  O  O20  1  0.203  0.845  0.916  1.0
  O  O21  1  0.653  0.848  0.916  1.0
  O  O22  1  0.003  0.493  0.756  1.0
  O  O23  1  0.326  0.645  0.581  1.0
  O  O24  1  0.483  0.497  0.756  1.0
  O  O25  1  0.177  0.343  0.422  1.0
  O  O26  1  0.166  0.337  0.910  1.0
  O  O27  1  0.851  0.162  0.578  1.0
  O  O28  1  1.000  0.015  0.755  1.0
  O  O29  1  0.320  0.168  0.578  1.0
  O  O30  1  0.680  0.832  0.422  1.0
  O  O31  1  0.001  0.988  0.246  1.0
  O  O32  1  0.150  0.838  0.422  1.0
  O  O33  1  0.837  0.661  0.095  1.0
  O  O34  1  0.822  0.658  0.580  1.0
  O  O35  1  0.518  0.506  0.246  1.0
  O  O36  1  0.999  0.509  0.245  1.0
  O  O37  1  0.673  0.354  0.419  1.0
  O  O38  1  0.341  0.154  0.083  1.0
  O  O39  1  0.806  0.156  0.082  1.0
  O  O40  1  0.495  0.003  0.243  1.0
  O  O41  1  0.339  0.690  0.082  1.0
[/CIF]
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