MgFe2(CoO4)2 is beta indium sulfide-derived structured and crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form MgO6 octahedra that share corners with four equivalent Co(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and faces with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-50°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form FeO6 octahedra that share corners with four equivalent Co(1)O6 octahedra, corners with four equivalent Co(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-54°. In the second Fe site, Fe(2) is bonded to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form FeO6 octahedra that share corners with four equivalent Co(1)O6 octahedra, corners with four equivalent Co(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-53°. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form CoO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-54°. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form CoO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and faces with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-49°. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(2), and one Co(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Co(1), and one Co(2) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Co(1), and one Co(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Co(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Fe(2), and one Co(2) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Co(1), and one Co(2) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Co(1), and one Co(2) atom. In the eighth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Fe(2), and one Co(2) atom.
MgFe2(CoO4)2 is beta indium sulfide-derived structured and crystallizes in the triclinic P1 space group. Mg(1) is bonded to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form MgO6 octahedra that share corners with four equivalent Co(1)O6 octahedra, edges with two equivalent Fe(1)O6 octahedra, edges with two equivalent Fe(2)O6 octahedra, and faces with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-50°. The Mg(1)-O(2) bond length is 2.03 Å. The Mg(1)-O(3) bond length is 2.01 Å. The Mg(1)-O(5) bond length is 1.99 Å. The Mg(1)-O(6) bond length is 1.98 Å. The Mg(1)-O(7) bond length is 1.98 Å. The Mg(1)-O(8) bond length is 1.99 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(8) atom to form FeO6 octahedra that share corners with four equivalent Co(1)O6 octahedra, corners with four equivalent Co(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-54°. The Fe(1)-O(1) bond length is 2.05 Å. The Fe(1)-O(2) bond length is 2.25 Å. The Fe(1)-O(3) bond length is 2.24 Å. The Fe(1)-O(4) bond length is 1.98 Å. The Fe(1)-O(5) bond length is 1.97 Å. The Fe(1)-O(8) bond length is 1.96 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(4), one O(5), one O(6), one O(7), and one O(8) atom to form FeO6 octahedra that share corners with four equivalent Co(1)O6 octahedra, corners with four equivalent Co(2)O6 octahedra, edges with two equivalent Mg(1)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-53°. The Fe(2)-O(1) bond length is 2.04 Å. The Fe(2)-O(4) bond length is 1.96 Å. The Fe(2)-O(5) bond length is 2.04 Å. The Fe(2)-O(6) bond length is 2.11 Å. The Fe(2)-O(7) bond length is 2.13 Å. The Fe(2)-O(8) bond length is 2.03 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to one O(1), one O(2), one O(3), one O(4), one O(6), and one O(7) atom to form CoO6 octahedra that share corners with four equivalent Mg(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Co(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 38-54°. The Co(1)-O(1) bond length is 1.84 Å. The Co(1)-O(2) bond length is 1.98 Å. The Co(1)-O(3) bond length is 1.95 Å. The Co(1)-O(4) bond length is 1.95 Å. The Co(1)-O(6) bond length is 2.17 Å. The Co(1)-O(7) bond length is 2.07 Å. In the second Co site, Co(2) is bonded to one O(2), one O(3), one O(5), one O(6), one O(7), and one O(8) atom to form CoO6 octahedra that share corners with four equivalent Fe(1)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, edges with two equivalent Co(1)O6 octahedra, and faces with two equivalent Mg(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-49°. The Co(2)-O(2) bond length is 1.93 Å. The Co(2)-O(3) bond length is 1.96 Å. The Co(2)-O(5) bond length is 1.98 Å. The Co(2)-O(6) bond length is 1.85 Å. The Co(2)-O(7) bond length is 1.89 Å. The Co(2)-O(8) bond length is 2.00 Å. There are eight inequivalent O sites. In the first O site, O(1) is bonded in a distorted T-shaped geometry to one Fe(1), one Fe(2), and one Co(1) atom. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Co(1), and one Co(2) atom. In the third O site, O(3) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Co(1), and one Co(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Fe(1), one Fe(2), and one Co(1) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Fe(2), and one Co(2) atom. In the sixth O site, O(6) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Co(1), and one Co(2) atom. In the seventh O site, O(7) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(2), one Co(1), and one Co(2) atom. In the eighth O site, O(8) is bonded in a rectangular see-saw-like geometry to one Mg(1), one Fe(1), one Fe(2), and one Co(2) atom.