The material described by Mg4FeO5 is Caswellsilverite-like structured and crystallizes in the triclinic P-1 space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(10), one O(11), one O(4), one O(6), and one O(8) atom to form MgO6 octahedra that share  a cornercorner with one Mg(3)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with three equivalent Mg(8)O6 octahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with two equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second Mg site, Mg(2) is bonded to one O(10), one O(11), one O(3), one O(5), one O(7), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(7)O6 octahedra, corners with two equivalent Mg(5)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(7)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, edges with two equivalent Mg(8)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the third Mg site, Mg(3) is bonded to one O(1), one O(10), one O(4), one O(6), one O(8), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with three equivalent Mg(6)O6 octahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(8)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with two equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-5°. In the fourth Mg site, Mg(4) is bonded to one O(11), one O(2), one O(5), one O(7), one O(8), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, corners with two equivalent Mg(7)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, edges with two equivalent Mg(8)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the fifth Mg site, Mg(5) is bonded to one O(4), one O(5), one O(7), one O(8), and two equivalent O(1) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Mg(7)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Mg(8)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(7)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the sixth Mg site, Mg(6) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Mg(6)O6 octahedra, corners with three equivalent Mg(3)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Mg(7)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, and edges with three equivalent Mg(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the seventh Mg site, Mg(7) is bonded to one O(10), one O(5), one O(6), one O(7), and two equivalent O(1) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Mg(5)O6 octahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Mg(7)O6 octahedra,  an edgeedge with one Mg(8)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the eighth Mg site, Mg(8) is bonded to one O(11), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form MgO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Mg(8)O6 octahedra, corners with three equivalent Mg(1)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Mg(7)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, and edges with three equivalent Mg(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(11), two equivalent O(4), and two equivalent O(9) atoms to form FeO6 octahedra that share corners with two equivalent Mg(5)O6 octahedra, corners with four equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, edges with two equivalent Mg(8)O6 octahedra, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Fe site, Fe(2) is bonded to one O(5), one O(7), two equivalent O(10), and two equivalent O(8) atoms to form FeO6 octahedra that share  a cornercorner with one Mg(6)O6 octahedra,  a cornercorner with one Mg(8)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, edges with two equivalent Mg(7)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. In the third Fe site, Fe(3) is bonded to two equivalent O(11), two equivalent O(6), and two equivalent O(9) atoms to form FeO6 octahedra that share corners with two equivalent Mg(7)O6 octahedra, corners with four equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, edges with two equivalent Mg(8)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are eleven inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Mg(3), two equivalent Mg(5), and two equivalent Mg(7) atoms to form OMg6 octahedra that share  a cornercorner with one O(11)Mg4Fe2 octahedra,  a cornercorner with one O(9)Mg4Fe2 octahedra, corners with two equivalent O(5)Mg5Fe octahedra, corners with two equivalent O(7)Mg5Fe octahedra,  an edgeedge with one O(5)Mg5Fe octahedra,  an edgeedge with one O(7)Mg5Fe octahedra, edges with two equivalent O(10)Mg4Fe2 octahedra, edges with two equivalent O(8)Mg4Fe2 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(6)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second O site, O(2) is bonded to two equivalent Mg(4), two equivalent Mg(6), and two equivalent Mg(8) atoms to form OMg6 octahedra that share corners with two equivalent O(8)Mg4Fe2 octahedra, corners with four equivalent O(6)Mg5Fe octahedra, edges with two equivalent O(11)Mg4Fe2 octahedra, edges with two equivalent O(9)Mg4Fe2 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(5)Mg5Fe octahedra, edges with two equivalent O(7)Mg5Fe octahedra, and edges with two equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 2-3°. In the third O site, O(3) is bonded to two equivalent Mg(2), two equivalent Mg(6), and two equivalent Mg(8) atoms to form OMg6 octahedra that share corners with two equivalent O(10)Mg4Fe2 octahedra, corners with four equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(11)Mg4Fe2 octahedra, edges with two equivalent O(9)Mg4Fe2 octahedra, edges with two equivalent O(5)Mg5Fe octahedra, edges with two equivalent O(6)Mg5Fe octahedra, edges with two equivalent O(7)Mg5Fe octahedra, and edges with two equivalent O(2)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the fourth O site, O(4) is bonded to one Mg(1), one Mg(3), one Mg(5), one Mg(6), one Mg(8), and one Fe(1) atom to form OMg5Fe octahedra that share  a cornercorner with one O(8)Mg4Fe2 octahedra,  a cornercorner with one O(4)Mg5Fe octahedra, corners with two equivalent O(10)Mg4Fe2 octahedra, corners with two equivalent O(3)Mg6 octahedra,  an edgeedge with one O(8)Mg4Fe2 octahedra,  an edgeedge with one O(5)Mg5Fe octahedra,  an edgeedge with one O(7)Mg5Fe octahedra,  an edgeedge with one O(2)Mg6 octahedra, edges with two equivalent O(11)Mg4Fe2 octahedra, edges with two equivalent O(9)Mg4Fe2 octahedra, edges with two equivalent O(6)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the fifth O site, O(5) is bonded to one Mg(2), one Mg(4), one Mg(5), one Mg(6), one Mg(7), and one Fe(2) atom to form OMg5Fe octahedra that share  a cornercorner with one O(7)Mg5Fe octahedra, corners with two equivalent O(1)Mg6 octahedra, corners with three equivalent O(9)Mg4Fe2 octahedra,  an edgeedge with one O(11)Mg4Fe2 octahedra,  an edgeedge with one O(4)Mg5Fe octahedra,  an edgeedge with one O(6)Mg5Fe octahedra,  an edgeedge with one O(1)Mg6 octahedra,  an edgeedge with one O(2)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(10)Mg4Fe2 octahedra, edges with two equivalent O(8)Mg4Fe2 octahedra, and edges with two equivalent O(7)Mg5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the sixth O site, O(6) is bonded to one Mg(1), one Mg(3), one Mg(6), one Mg(7), one Mg(8), and one Fe(3) atom to form OMg5Fe octahedra that share  a cornercorner with one O(10)Mg4Fe2 octahedra,  a cornercorner with one O(6)Mg5Fe octahedra, corners with two equivalent O(8)Mg4Fe2 octahedra, corners with two equivalent O(2)Mg6 octahedra,  an edgeedge with one O(10)Mg4Fe2 octahedra,  an edgeedge with one O(5)Mg5Fe octahedra,  an edgeedge with one O(7)Mg5Fe octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(11)Mg4Fe2 octahedra, edges with two equivalent O(9)Mg4Fe2 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the seventh O site, O(7) is bonded to one Mg(2), one Mg(4), one Mg(5), one Mg(7), one Mg(8), and one Fe(2) atom to form OMg5Fe octahedra that share  a cornercorner with one O(5)Mg5Fe octahedra, corners with two equivalent O(1)Mg6 octahedra, corners with three equivalent O(11)Mg4Fe2 octahedra,  an edgeedge with one O(9)Mg4Fe2 octahedra,  an edgeedge with one O(4)Mg5Fe octahedra,  an edgeedge with one O(6)Mg5Fe octahedra,  an edgeedge with one O(1)Mg6 octahedra,  an edgeedge with one O(2)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(10)Mg4Fe2 octahedra, edges with two equivalent O(8)Mg4Fe2 octahedra, and edges with two equivalent O(5)Mg5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the eighth O site, O(8) is bonded to one Mg(1), one Mg(3), one Mg(4), one Mg(5), and two equivalent Fe(2) atoms to form OMg4Fe2 octahedra that share  a cornercorner with one O(4)Mg5Fe octahedra,  a cornercorner with one O(2)Mg6 octahedra, corners with two equivalent O(10)Mg4Fe2 octahedra, corners with two equivalent O(6)Mg5Fe octahedra,  an edgeedge with one O(11)Mg4Fe2 octahedra,  an edgeedge with one O(8)Mg4Fe2 octahedra,  an edgeedge with one O(9)Mg4Fe2 octahedra,  an edgeedge with one O(4)Mg5Fe octahedra, edges with two equivalent O(10)Mg4Fe2 octahedra, edges with two equivalent O(5)Mg5Fe octahedra, edges with two equivalent O(7)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the ninth O site, O(9) is bonded to one Mg(2), one Mg(3), one Mg(4), one Mg(6), one Fe(1), and one Fe(3) atom to form OMg4Fe2 octahedra that share  a cornercorner with one O(1)Mg6 octahedra, corners with two equivalent O(9)Mg4Fe2 octahedra, corners with three equivalent O(5)Mg5Fe octahedra,  an edgeedge with one O(10)Mg4Fe2 octahedra,  an edgeedge with one O(8)Mg4Fe2 octahedra,  an edgeedge with one O(7)Mg5Fe octahedra,  an edgeedge with one O(2)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(6)Mg5Fe octahedra, and edges with three equivalent O(11)Mg4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the tenth O site, O(10) is bonded to one Mg(1), one Mg(2), one Mg(3), one Mg(7), and two equivalent Fe(2) atoms to form OMg4Fe2 octahedra that share  a cornercorner with one O(6)Mg5Fe octahedra,  a cornercorner with one O(3)Mg6 octahedra, corners with two equivalent O(8)Mg4Fe2 octahedra, corners with two equivalent O(4)Mg5Fe octahedra,  an edgeedge with one O(10)Mg4Fe2 octahedra,  an edgeedge with one O(11)Mg4Fe2 octahedra,  an edgeedge with one O(9)Mg4Fe2 octahedra,  an edgeedge with one O(6)Mg5Fe octahedra, edges with two equivalent O(8)Mg4Fe2 octahedra, edges with two equivalent O(5)Mg5Fe octahedra, edges with two equivalent O(7)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the eleventh O site, O(11) is bonded to one Mg(1), one Mg(2), one Mg(4), one Mg(8), one Fe(1), and one Fe(3) atom to form OMg4Fe2 octahedra that share  a cornercorner with one O(1)Mg6 octahedra, corners with two equivalent O(11)Mg4Fe2 octahedra, corners with three equivalent O(7)Mg5Fe octahedra,  an edgeedge with one O(10)Mg4Fe2 octahedra,  an edgeedge with one O(8)Mg4Fe2 octahedra,  an edgeedge with one O(5)Mg5Fe octahedra,  an edgeedge with one O(2)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(6)Mg5Fe octahedra, and edges with three equivalent O(9)Mg4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. is represented by the CIF file [CIF]
data_Mg4FeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.978
_cell_length_b   5.162
_cell_length_c   6.688
_cell_angle_alpha   97.692
_cell_angle_beta   102.664
_cell_angle_gamma   106.045
_symmetry_Int_Tables_number   1
_cell_volume   94.316
_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
  Fe  Fe0  1  1.000  0.000  1.000  1.0
  Mg  Mg1  1  0.407  0.605  0.202  1.0
  Mg  Mg2  1  0.593  0.395  0.798  1.0
  Mg  Mg3  1  0.798  0.202  0.399  1.0
  Mg  Mg4  1  0.202  0.798  0.601  1.0
  O  O5  1  0.500  0.500  0.500  1.0
  O  O6  1  0.897  0.100  0.695  1.0
  O  O7  1  0.103  0.900  0.305  1.0
  O  O8  1  0.721  0.311  0.104  1.0
  O  O9  1  0.279  0.689  0.896  1.0
[/CIF]
.
The material described by Mg4FeO5 is Caswellsilverite-like structured and crystallizes in the triclinic P-1 space group. There are eight inequivalent Mg sites. In the first Mg site, Mg(1) is bonded to one O(1), one O(10), one O(11), one O(4), one O(6), and one O(8) atom to form MgO6 octahedra that share  a cornercorner with one Mg(3)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with three equivalent Mg(8)O6 octahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with two equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second Mg site, Mg(2) is bonded to one O(10), one O(11), one O(3), one O(5), one O(7), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Mg(7)O6 octahedra, corners with two equivalent Mg(5)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(7)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, edges with two equivalent Mg(8)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the third Mg site, Mg(3) is bonded to one O(1), one O(10), one O(4), one O(6), one O(8), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Mg(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with three equivalent Mg(6)O6 octahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(8)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(2)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with two equivalent Mg(7)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-5°. In the fourth Mg site, Mg(4) is bonded to one O(11), one O(2), one O(5), one O(7), one O(8), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Mg(5)O6 octahedra, corners with two equivalent Mg(7)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, edges with two equivalent Mg(8)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the fifth Mg site, Mg(5) is bonded to one O(4), one O(5), one O(7), one O(8), and two equivalent O(1) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(4)O6 octahedra,  a cornercorner with one Fe(1)O6 octahedra, corners with two equivalent Mg(2)O6 octahedra, corners with two equivalent Mg(7)O6 octahedra,  an edgeedge with one Mg(4)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Mg(8)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(7)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the sixth Mg site, Mg(6) is bonded to one O(2), one O(3), one O(4), one O(5), one O(6), and one O(9) atom to form MgO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Mg(6)O6 octahedra, corners with three equivalent Mg(3)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Mg(7)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, and edges with three equivalent Mg(8)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the seventh Mg site, Mg(7) is bonded to one O(10), one O(5), one O(6), one O(7), and two equivalent O(1) atoms to form MgO6 octahedra that share  a cornercorner with one Mg(2)O6 octahedra,  a cornercorner with one Fe(3)O6 octahedra, corners with two equivalent Mg(4)O6 octahedra, corners with two equivalent Mg(5)O6 octahedra,  an edgeedge with one Mg(2)O6 octahedra,  an edgeedge with one Mg(6)O6 octahedra,  an edgeedge with one Mg(7)O6 octahedra,  an edgeedge with one Mg(8)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-5°. In the eighth Mg site, Mg(8) is bonded to one O(11), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form MgO6 octahedra that share  a cornercorner with one Fe(2)O6 octahedra, corners with two equivalent Mg(8)O6 octahedra, corners with three equivalent Mg(1)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra,  an edgeedge with one Mg(5)O6 octahedra,  an edgeedge with one Mg(7)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra,  an edgeedge with one Fe(3)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, and edges with three equivalent Mg(6)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(11), two equivalent O(4), and two equivalent O(9) atoms to form FeO6 octahedra that share corners with two equivalent Mg(5)O6 octahedra, corners with four equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, edges with two equivalent Mg(8)O6 octahedra, and edges with two equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the second Fe site, Fe(2) is bonded to one O(5), one O(7), two equivalent O(10), and two equivalent O(8) atoms to form FeO6 octahedra that share  a cornercorner with one Mg(6)O6 octahedra,  a cornercorner with one Mg(8)O6 octahedra, corners with two equivalent Mg(1)O6 octahedra, corners with two equivalent Mg(3)O6 octahedra,  an edgeedge with one Mg(1)O6 octahedra,  an edgeedge with one Mg(3)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(5)O6 octahedra, edges with two equivalent Mg(7)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 1-3°. In the third Fe site, Fe(3) is bonded to two equivalent O(11), two equivalent O(6), and two equivalent O(9) atoms to form FeO6 octahedra that share corners with two equivalent Mg(7)O6 octahedra, corners with four equivalent Mg(4)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mg(2)O6 octahedra, edges with two equivalent Mg(3)O6 octahedra, edges with two equivalent Mg(6)O6 octahedra, edges with two equivalent Mg(8)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. There are eleven inequivalent O sites. In the first O site, O(1) is bonded to one Mg(1), one Mg(3), two equivalent Mg(5), and two equivalent Mg(7) atoms to form OMg6 octahedra that share  a cornercorner with one O(11)Mg4Fe2 octahedra,  a cornercorner with one O(9)Mg4Fe2 octahedra, corners with two equivalent O(5)Mg5Fe octahedra, corners with two equivalent O(7)Mg5Fe octahedra,  an edgeedge with one O(5)Mg5Fe octahedra,  an edgeedge with one O(7)Mg5Fe octahedra, edges with two equivalent O(10)Mg4Fe2 octahedra, edges with two equivalent O(8)Mg4Fe2 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(6)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 1-4°. In the second O site, O(2) is bonded to two equivalent Mg(4), two equivalent Mg(6), and two equivalent Mg(8) atoms to form OMg6 octahedra that share corners with two equivalent O(8)Mg4Fe2 octahedra, corners with four equivalent O(6)Mg5Fe octahedra, edges with two equivalent O(11)Mg4Fe2 octahedra, edges with two equivalent O(9)Mg4Fe2 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(5)Mg5Fe octahedra, edges with two equivalent O(7)Mg5Fe octahedra, and edges with two equivalent O(3)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 2-3°. In the third O site, O(3) is bonded to two equivalent Mg(2), two equivalent Mg(6), and two equivalent Mg(8) atoms to form OMg6 octahedra that share corners with two equivalent O(10)Mg4Fe2 octahedra, corners with four equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(11)Mg4Fe2 octahedra, edges with two equivalent O(9)Mg4Fe2 octahedra, edges with two equivalent O(5)Mg5Fe octahedra, edges with two equivalent O(6)Mg5Fe octahedra, edges with two equivalent O(7)Mg5Fe octahedra, and edges with two equivalent O(2)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the fourth O site, O(4) is bonded to one Mg(1), one Mg(3), one Mg(5), one Mg(6), one Mg(8), and one Fe(1) atom to form OMg5Fe octahedra that share  a cornercorner with one O(8)Mg4Fe2 octahedra,  a cornercorner with one O(4)Mg5Fe octahedra, corners with two equivalent O(10)Mg4Fe2 octahedra, corners with two equivalent O(3)Mg6 octahedra,  an edgeedge with one O(8)Mg4Fe2 octahedra,  an edgeedge with one O(5)Mg5Fe octahedra,  an edgeedge with one O(7)Mg5Fe octahedra,  an edgeedge with one O(2)Mg6 octahedra, edges with two equivalent O(11)Mg4Fe2 octahedra, edges with two equivalent O(9)Mg4Fe2 octahedra, edges with two equivalent O(6)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the fifth O site, O(5) is bonded to one Mg(2), one Mg(4), one Mg(5), one Mg(6), one Mg(7), and one Fe(2) atom to form OMg5Fe octahedra that share  a cornercorner with one O(7)Mg5Fe octahedra, corners with two equivalent O(1)Mg6 octahedra, corners with three equivalent O(9)Mg4Fe2 octahedra,  an edgeedge with one O(11)Mg4Fe2 octahedra,  an edgeedge with one O(4)Mg5Fe octahedra,  an edgeedge with one O(6)Mg5Fe octahedra,  an edgeedge with one O(1)Mg6 octahedra,  an edgeedge with one O(2)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(10)Mg4Fe2 octahedra, edges with two equivalent O(8)Mg4Fe2 octahedra, and edges with two equivalent O(7)Mg5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the sixth O site, O(6) is bonded to one Mg(1), one Mg(3), one Mg(6), one Mg(7), one Mg(8), and one Fe(3) atom to form OMg5Fe octahedra that share  a cornercorner with one O(10)Mg4Fe2 octahedra,  a cornercorner with one O(6)Mg5Fe octahedra, corners with two equivalent O(8)Mg4Fe2 octahedra, corners with two equivalent O(2)Mg6 octahedra,  an edgeedge with one O(10)Mg4Fe2 octahedra,  an edgeedge with one O(5)Mg5Fe octahedra,  an edgeedge with one O(7)Mg5Fe octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(11)Mg4Fe2 octahedra, edges with two equivalent O(9)Mg4Fe2 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the seventh O site, O(7) is bonded to one Mg(2), one Mg(4), one Mg(5), one Mg(7), one Mg(8), and one Fe(2) atom to form OMg5Fe octahedra that share  a cornercorner with one O(5)Mg5Fe octahedra, corners with two equivalent O(1)Mg6 octahedra, corners with three equivalent O(11)Mg4Fe2 octahedra,  an edgeedge with one O(9)Mg4Fe2 octahedra,  an edgeedge with one O(4)Mg5Fe octahedra,  an edgeedge with one O(6)Mg5Fe octahedra,  an edgeedge with one O(1)Mg6 octahedra,  an edgeedge with one O(2)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(10)Mg4Fe2 octahedra, edges with two equivalent O(8)Mg4Fe2 octahedra, and edges with two equivalent O(5)Mg5Fe octahedra. The corner-sharing octahedral tilt angles range from 0-2°. In the eighth O site, O(8) is bonded to one Mg(1), one Mg(3), one Mg(4), one Mg(5), and two equivalent Fe(2) atoms to form OMg4Fe2 octahedra that share  a cornercorner with one O(4)Mg5Fe octahedra,  a cornercorner with one O(2)Mg6 octahedra, corners with two equivalent O(10)Mg4Fe2 octahedra, corners with two equivalent O(6)Mg5Fe octahedra,  an edgeedge with one O(11)Mg4Fe2 octahedra,  an edgeedge with one O(8)Mg4Fe2 octahedra,  an edgeedge with one O(9)Mg4Fe2 octahedra,  an edgeedge with one O(4)Mg5Fe octahedra, edges with two equivalent O(10)Mg4Fe2 octahedra, edges with two equivalent O(5)Mg5Fe octahedra, edges with two equivalent O(7)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. In the ninth O site, O(9) is bonded to one Mg(2), one Mg(3), one Mg(4), one Mg(6), one Fe(1), and one Fe(3) atom to form OMg4Fe2 octahedra that share  a cornercorner with one O(1)Mg6 octahedra, corners with two equivalent O(9)Mg4Fe2 octahedra, corners with three equivalent O(5)Mg5Fe octahedra,  an edgeedge with one O(10)Mg4Fe2 octahedra,  an edgeedge with one O(8)Mg4Fe2 octahedra,  an edgeedge with one O(7)Mg5Fe octahedra,  an edgeedge with one O(2)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(6)Mg5Fe octahedra, and edges with three equivalent O(11)Mg4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the tenth O site, O(10) is bonded to one Mg(1), one Mg(2), one Mg(3), one Mg(7), and two equivalent Fe(2) atoms to form OMg4Fe2 octahedra that share  a cornercorner with one O(6)Mg5Fe octahedra,  a cornercorner with one O(3)Mg6 octahedra, corners with two equivalent O(8)Mg4Fe2 octahedra, corners with two equivalent O(4)Mg5Fe octahedra,  an edgeedge with one O(10)Mg4Fe2 octahedra,  an edgeedge with one O(11)Mg4Fe2 octahedra,  an edgeedge with one O(9)Mg4Fe2 octahedra,  an edgeedge with one O(6)Mg5Fe octahedra, edges with two equivalent O(8)Mg4Fe2 octahedra, edges with two equivalent O(5)Mg5Fe octahedra, edges with two equivalent O(7)Mg5Fe octahedra, and edges with two equivalent O(1)Mg6 octahedra. The corner-sharing octahedral tilt angles range from 0-4°. In the eleventh O site, O(11) is bonded to one Mg(1), one Mg(2), one Mg(4), one Mg(8), one Fe(1), and one Fe(3) atom to form OMg4Fe2 octahedra that share  a cornercorner with one O(1)Mg6 octahedra, corners with two equivalent O(11)Mg4Fe2 octahedra, corners with three equivalent O(7)Mg5Fe octahedra,  an edgeedge with one O(10)Mg4Fe2 octahedra,  an edgeedge with one O(8)Mg4Fe2 octahedra,  an edgeedge with one O(5)Mg5Fe octahedra,  an edgeedge with one O(2)Mg6 octahedra,  an edgeedge with one O(3)Mg6 octahedra, edges with two equivalent O(4)Mg5Fe octahedra, edges with two equivalent O(6)Mg5Fe octahedra, and edges with three equivalent O(9)Mg4Fe2 octahedra. The corner-sharing octahedral tilt angles range from 0-3°. is represented by the CIF file [CIF]
data_Mg4FeO5
_symmetry_space_group_name_H-M   'P 1'
_cell_length_a   2.978
_cell_length_b   5.162
_cell_length_c   6.688
_cell_angle_alpha   97.692
_cell_angle_beta   102.664
_cell_angle_gamma   106.045
_symmetry_Int_Tables_number   1
_cell_volume   94.316
_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
  Fe  Fe0  1  1.000  0.000  1.000  1.0
  Mg  Mg1  1  0.407  0.605  0.202  1.0
  Mg  Mg2  1  0.593  0.395  0.798  1.0
  Mg  Mg3  1  0.798  0.202  0.399  1.0
  Mg  Mg4  1  0.202  0.798  0.601  1.0
  O  O5  1  0.500  0.500  0.500  1.0
  O  O6  1  0.897  0.100  0.695  1.0
  O  O7  1  0.103  0.900  0.305  1.0
  O  O8  1  0.721  0.311  0.104  1.0
  O  O9  1  0.279  0.689  0.896  1.0
[/CIF]
.