Ba2YCoO5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(2), two equivalent O(3), two equivalent O(4), two equivalent O(5), and three equivalent O(1) atoms. Y(1) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form YO6 octahedra that share corners with two equivalent Y(1)O6 octahedra and corners with four equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. Co(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form CoO4 tetrahedra that share corners with four equivalent Y(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-45°. There are five inequivalent O sites. In the first O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(1), and one Co(1) atom. In the second O site, O(1) is bonded in a 6-coordinate geometry to one Ba(1), three equivalent Ba(2), one Y(1), and one Co(1) atom. In the third O site, O(2) is bonded in a 5-coordinate geometry to one Ba(2), two equivalent Ba(1), one Y(1), and one Co(1) atom. In the fourth O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Y(1) atoms. In the fifth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(1), and one Co(1) atom.
Ba2YCoO5 crystallizes in the monoclinic P2_1/c space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 9-coordinate geometry to one O(1), two equivalent O(2), two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms. The Ba(1)-O(1) bond length is 2.83 Å. There is one shorter (2.98 Å) and one longer (3.23 Å) Ba(1)-O(2) bond length. There is one shorter (2.70 Å) and one longer (3.17 Å) Ba(1)-O(3) bond length. There is one shorter (2.76 Å) and one longer (3.08 Å) Ba(1)-O(4) bond length. There is one shorter (2.75 Å) and one longer (3.22 Å) Ba(1)-O(5) bond length. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(2), two equivalent O(3), two equivalent O(4), two equivalent O(5), and three equivalent O(1) atoms. The Ba(2)-O(2) bond length is 2.71 Å. There is one shorter (2.72 Å) and one longer (3.17 Å) Ba(2)-O(3) bond length. There is one shorter (2.81 Å) and one longer (3.15 Å) Ba(2)-O(4) bond length. There is one shorter (2.81 Å) and one longer (3.18 Å) Ba(2)-O(5) bond length. There are a spread of Ba(2)-O(1) bond distances ranging from 3.02-3.13 Å. Y(1) is bonded to one O(1), one O(2), one O(4), one O(5), and two equivalent O(3) atoms to form YO6 octahedra that share corners with two equivalent Y(1)O6 octahedra and corners with four equivalent Co(1)O4 tetrahedra. The corner-sharing octahedral tilt angles are 18°. The Y(1)-O(1) bond length is 2.32 Å. The Y(1)-O(2) bond length is 2.35 Å. The Y(1)-O(4) bond length is 2.26 Å. The Y(1)-O(5) bond length is 2.26 Å. There is one shorter (2.17 Å) and one longer (2.18 Å) Y(1)-O(3) bond length. Co(1) is bonded to one O(1), one O(2), one O(4), and one O(5) atom to form CoO4 tetrahedra that share corners with four equivalent Y(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 6-45°. The Co(1)-O(1) bond length is 1.83 Å. The Co(1)-O(2) bond length is 1.81 Å. The Co(1)-O(4) bond length is 1.91 Å. The Co(1)-O(5) bond length is 1.90 Å. There are five inequivalent O sites. In the first O site, O(5) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(1), and one Co(1) atom. In the second O site, O(1) is bonded in a 6-coordinate geometry to one Ba(1), three equivalent Ba(2), one Y(1), and one Co(1) atom. In the third O site, O(2) is bonded in a 5-coordinate geometry to one Ba(2), two equivalent Ba(1), one Y(1), and one Co(1) atom. In the fourth O site, O(3) is bonded in a 4-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), and two equivalent Y(1) atoms. In the fifth O site, O(4) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(1), and one Co(1) atom.