MgMn4FeO8 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with six equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-17°. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mn(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-14°. In the second Mn site, Mn(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-14°. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-17°. In the fourth Mn site, Mn(4) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. There are four inequivalent O sites. In the first O site, O(1) is bonded in a see-saw-like geometry to one Mg(1), one Mn(3), one Mn(4), and one Fe(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mn(1), one Mn(2), one Mn(4), and one Fe(1) atom. In the third O site, O(3) is bonded to one Mg(1), one Mn(1), one Mn(2), one Mn(3), and one Fe(1) atom to form OMgMn3Fe square pyramids that share corners with five equivalent O(3)MgMn3Fe square pyramids and edges with four equivalent O(4)MgMn4 square pyramids. In the fourth O site, O(4) is bonded to one Mg(1), one Mn(1), one Mn(2), one Mn(3), and one Mn(4) atom to form OMgMn4 square pyramids that share corners with five equivalent O(4)MgMn4 square pyramids and edges with four equivalent O(3)MgMn3Fe square pyramids.
MgMn4FeO8 crystallizes in the triclinic P-1 space group. Mg(1) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MgO6 octahedra that share corners with six equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-17°. Both Mg(1)-O(1) bond lengths are 2.10 Å. Both Mg(1)-O(3) bond lengths are 2.14 Å. Both Mg(1)-O(4) bond lengths are 2.10 Å. There are four inequivalent Mn sites. In the first Mn site, Mn(1) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mn(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-14°. Both Mn(1)-O(2) bond lengths are 2.15 Å. Both Mn(1)-O(3) bond lengths are 2.17 Å. Both Mn(1)-O(4) bond lengths are 2.13 Å. In the second Mn site, Mn(2) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mn(1)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-14°. Both Mn(2)-O(2) bond lengths are 2.10 Å. Both Mn(2)-O(3) bond lengths are 2.15 Å. Both Mn(2)-O(4) bond lengths are 2.25 Å. In the third Mn site, Mn(3) is bonded to two equivalent O(1), two equivalent O(3), and two equivalent O(4) atoms to form MnO6 octahedra that share corners with six equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(4)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 8-17°. Both Mn(3)-O(1) bond lengths are 2.16 Å. Both Mn(3)-O(3) bond lengths are 2.24 Å. Both Mn(3)-O(4) bond lengths are 2.21 Å. In the fourth Mn site, Mn(4) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(4) atoms to form MnO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. Both Mn(4)-O(1) bond lengths are 1.94 Å. Both Mn(4)-O(2) bond lengths are 1.97 Å. Both Mn(4)-O(4) bond lengths are 1.94 Å. Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms to form FeO6 octahedra that share edges with two equivalent Mg(1)O6 octahedra, edges with two equivalent Mn(1)O6 octahedra, edges with two equivalent Mn(2)O6 octahedra, edges with two equivalent Mn(3)O6 octahedra, and edges with two equivalent Mn(4)O6 octahedra. Both Fe(1)-O(1) bond lengths are 1.98 Å. Both Fe(1)-O(2) bond lengths are 2.02 Å. Both Fe(1)-O(3) bond lengths are 1.96 Å. There are four inequivalent O sites. In the first O site, O(1) is bonded in a see-saw-like geometry to one Mg(1), one Mn(3), one Mn(4), and one Fe(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mn(1), one Mn(2), one Mn(4), and one Fe(1) atom. In the third O site, O(3) is bonded to one Mg(1), one Mn(1), one Mn(2), one Mn(3), and one Fe(1) atom to form OMgMn3Fe square pyramids that share corners with five equivalent O(3)MgMn3Fe square pyramids and edges with four equivalent O(4)MgMn4 square pyramids. In the fourth O site, O(4) is bonded to one Mg(1), one Mn(1), one Mn(2), one Mn(3), and one Mn(4) atom to form OMgMn4 square pyramids that share corners with five equivalent O(4)MgMn4 square pyramids and edges with four equivalent O(3)MgMn3Fe square pyramids.