Mg2Co2O5 is Aluminum carbonitride-like structured and crystallizes in the orthorhombic Pbam space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Co(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing CoO5 trigonal bipyramids. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Mg(1) and two equivalent Co(1) atoms to form OMg4Co2 octahedra that share corners with four equivalent O(3)Mg2Co2 tetrahedra, corners with eight equivalent O(2)Mg2Co2 tetrahedra, edges with two equivalent O(1)Mg4Co2 octahedra, edges with two equivalent O(2)Mg2Co2 tetrahedra, and edges with four equivalent O(3)Mg2Co2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Mg(1) and two equivalent Co(1) atoms to form OMg2Co2 tetrahedra that share corners with four equivalent O(1)Mg4Co2 octahedra, corners with four equivalent O(2)Mg2Co2 tetrahedra, corners with four equivalent O(3)Mg2Co2 tetrahedra,  an edgeedge with one O(1)Mg4Co2 octahedra, and edges with two equivalent O(3)Mg2Co2 tetrahedra. The corner-sharing octahedral tilt angles range from 15-64°. In the third O site, O(3) is bonded to two equivalent Mg(1) and two equivalent Co(1) atoms to form distorted OMg2Co2 tetrahedra that share corners with two equivalent O(1)Mg4Co2 octahedra, corners with two equivalent O(3)Mg2Co2 tetrahedra, corners with four equivalent O(2)Mg2Co2 tetrahedra, edges with two equivalent O(1)Mg4Co2 octahedra,  an edgeedge with one O(3)Mg2Co2 tetrahedra, and edges with two equivalent O(2)Mg2Co2 tetrahedra. The corner-sharing octahedral tilt angles are 60°.
Mg2Co2O5 is Aluminum carbonitride-like structured and crystallizes in the orthorhombic Pbam space group. Mg(1) is bonded in a 6-coordinate geometry to two equivalent O(1), two equivalent O(2), and two equivalent O(3) atoms. Both Mg(1)-O(1) bond lengths are 2.36 Å. Both Mg(1)-O(2) bond lengths are 2.12 Å. There is one shorter (2.06 Å) and one longer (2.22 Å) Mg(1)-O(3) bond length. Co(1) is bonded to one O(1), two equivalent O(2), and two equivalent O(3) atoms to form corner-sharing CoO5 trigonal bipyramids. The Co(1)-O(1) bond length is 2.05 Å. There is one shorter (1.93 Å) and one longer (1.98 Å) Co(1)-O(2) bond length. Both Co(1)-O(3) bond lengths are 1.84 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to four equivalent Mg(1) and two equivalent Co(1) atoms to form OMg4Co2 octahedra that share corners with four equivalent O(3)Mg2Co2 tetrahedra, corners with eight equivalent O(2)Mg2Co2 tetrahedra, edges with two equivalent O(1)Mg4Co2 octahedra, edges with two equivalent O(2)Mg2Co2 tetrahedra, and edges with four equivalent O(3)Mg2Co2 tetrahedra. In the second O site, O(2) is bonded to two equivalent Mg(1) and two equivalent Co(1) atoms to form OMg2Co2 tetrahedra that share corners with four equivalent O(1)Mg4Co2 octahedra, corners with four equivalent O(2)Mg2Co2 tetrahedra, corners with four equivalent O(3)Mg2Co2 tetrahedra,  an edgeedge with one O(1)Mg4Co2 octahedra, and edges with two equivalent O(3)Mg2Co2 tetrahedra. The corner-sharing octahedral tilt angles range from 15-64°. In the third O site, O(3) is bonded to two equivalent Mg(1) and two equivalent Co(1) atoms to form distorted OMg2Co2 tetrahedra that share corners with two equivalent O(1)Mg4Co2 octahedra, corners with two equivalent O(3)Mg2Co2 tetrahedra, corners with four equivalent O(2)Mg2Co2 tetrahedra, edges with two equivalent O(1)Mg4Co2 octahedra,  an edgeedge with one O(3)Mg2Co2 tetrahedra, and edges with two equivalent O(2)Mg2Co2 tetrahedra. The corner-sharing octahedral tilt angles are 60°.