Sr2Co2O5 crystallizes in the orthorhombic Pnma space group. Sr(1) is bonded in a 9-coordinate geometry to one O(1), four equivalent O(2), and four equivalent O(3) atoms. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(2)O6 octahedra and corners with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 20°. In the second Co site, Co(2) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with four equivalent Co(2)O6 octahedra and corners with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 3°. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1) and two equivalent Co(1) atoms to form distorted OSr2Co2 tetrahedra that share corners with eight equivalent O(2)Sr4Co2 octahedra and corners with two equivalent O(1)Sr2Co2 tetrahedra. The corner-sharing octahedral tilt angles range from 24-69°. In the second O site, O(2) is bonded to four equivalent Sr(1) and two equivalent Co(2) atoms to form distorted OSr4Co2 octahedra that share corners with two equivalent O(2)Sr4Co2 octahedra, corners with four equivalent O(1)Sr2Co2 tetrahedra, edges with two equivalent O(2)Sr4Co2 octahedra, and faces with four equivalent O(2)Sr4Co2 octahedra. The corner-sharing octahedra are not tilted. In the third O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Sr(1), one Co(1), and one Co(2) atom.
Sr2Co2O5 crystallizes in the orthorhombic Pnma space group. Sr(1) is bonded in a 9-coordinate geometry to one O(1), four equivalent O(2), and four equivalent O(3) atoms. The Sr(1)-O(1) bond length is 2.41 Å. There are a spread of Sr(1)-O(2) bond distances ranging from 2.60-2.63 Å. There are a spread of Sr(1)-O(3) bond distances ranging from 2.58-2.92 Å. There are two inequivalent Co sites. In the first Co site, Co(1) is bonded to two equivalent O(1) and two equivalent O(3) atoms to form CoO4 tetrahedra that share corners with two equivalent Co(2)O6 octahedra and corners with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 20°. Both Co(1)-O(1) bond lengths are 1.92 Å. Both Co(1)-O(3) bond lengths are 1.82 Å. In the second Co site, Co(2) is bonded to two equivalent O(3) and four equivalent O(2) atoms to form CoO6 octahedra that share corners with four equivalent Co(2)O6 octahedra and corners with two equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 3°. Both Co(2)-O(3) bond lengths are 2.32 Å. All Co(2)-O(2) bond lengths are 1.90 Å. There are three inequivalent O sites. In the first O site, O(1) is bonded to two equivalent Sr(1) and two equivalent Co(1) atoms to form distorted OSr2Co2 tetrahedra that share corners with eight equivalent O(2)Sr4Co2 octahedra and corners with two equivalent O(1)Sr2Co2 tetrahedra. The corner-sharing octahedral tilt angles range from 24-69°. In the second O site, O(2) is bonded to four equivalent Sr(1) and two equivalent Co(2) atoms to form distorted OSr4Co2 octahedra that share corners with two equivalent O(2)Sr4Co2 octahedra, corners with four equivalent O(1)Sr2Co2 tetrahedra, edges with two equivalent O(2)Sr4Co2 octahedra, and faces with four equivalent O(2)Sr4Co2 octahedra. The corner-sharing octahedra are not tilted. In the third O site, O(3) is bonded in a 6-coordinate geometry to four equivalent Sr(1), one Co(1), and one Co(2) atom.