Ba3Y4O9 is Orthorhombic Perovskite-like structured and crystallizes in the triclinic P1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted trigonal planar geometry to one O(7), one O(8), and one O(9) atom. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. In the third Ba site, Ba(3) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom. There are four inequivalent Y sites. In the first Y site, Y(1) is bonded to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom to form corner-sharing YO6 octahedra. The corner-sharing octahedral tilt angles are 21°. In the second Y site, Y(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. In the third Y site, Y(3) is bonded to one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom to form corner-sharing YO6 octahedra. The corner-sharing octahedral tilt angles are 21°. In the fourth Y site, Y(4) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ba(3), one Y(1), one Y(2), and one Y(4) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ba(3), one Y(1), one Y(2), and one Y(4) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ba(3), one Y(1), one Y(2), and one Y(4) atom. In the fourth O site, O(4) is bonded in a distorted see-saw-like geometry to one Ba(2), one Y(2), one Y(3), and one Y(4) atom. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to one Ba(2), one Y(2), one Y(3), and one Y(4) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ba(2), one Y(2), one Y(3), and one Y(4) atom. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Y(1), and one Y(3) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Y(1), and one Y(3) atom. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Y(1), and one Y(3) atom.
Ba3Y4O9 is Orthorhombic Perovskite-like structured and crystallizes in the triclinic P1 space group. There are three inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a distorted trigonal planar geometry to one O(7), one O(8), and one O(9) atom. The Ba(1)-O(7) bond length is 2.66 Å. The Ba(1)-O(8) bond length is 2.64 Å. The Ba(1)-O(9) bond length is 2.72 Å. In the second Ba site, Ba(2) is bonded in a 6-coordinate geometry to one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom. The Ba(2)-O(4) bond length is 2.78 Å. The Ba(2)-O(5) bond length is 2.74 Å. The Ba(2)-O(6) bond length is 2.81 Å. The Ba(2)-O(7) bond length is 2.87 Å. The Ba(2)-O(8) bond length is 2.81 Å. The Ba(2)-O(9) bond length is 2.78 Å. In the third Ba site, Ba(3) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom. The Ba(3)-O(1) bond length is 2.80 Å. The Ba(3)-O(2) bond length is 2.76 Å. The Ba(3)-O(3) bond length is 2.75 Å. The Ba(3)-O(7) bond length is 2.79 Å. The Ba(3)-O(8) bond length is 2.80 Å. The Ba(3)-O(9) bond length is 2.81 Å. There are four inequivalent Y sites. In the first Y site, Y(1) is bonded to one O(1), one O(2), one O(3), one O(7), one O(8), and one O(9) atom to form corner-sharing YO6 octahedra. The corner-sharing octahedral tilt angles are 21°. The Y(1)-O(1) bond length is 2.28 Å. The Y(1)-O(2) bond length is 2.27 Å. The Y(1)-O(3) bond length is 2.24 Å. The Y(1)-O(7) bond length is 2.22 Å. The Y(1)-O(8) bond length is 2.31 Å. The Y(1)-O(9) bond length is 2.29 Å. In the second Y site, Y(2) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. The Y(2)-O(1) bond length is 2.26 Å. The Y(2)-O(2) bond length is 2.23 Å. The Y(2)-O(3) bond length is 2.30 Å. The Y(2)-O(4) bond length is 2.40 Å. The Y(2)-O(5) bond length is 2.38 Å. The Y(2)-O(6) bond length is 2.48 Å. In the third Y site, Y(3) is bonded to one O(4), one O(5), one O(6), one O(7), one O(8), and one O(9) atom to form corner-sharing YO6 octahedra. The corner-sharing octahedral tilt angles are 21°. The Y(3)-O(4) bond length is 2.30 Å. The Y(3)-O(5) bond length is 2.34 Å. The Y(3)-O(6) bond length is 2.24 Å. The Y(3)-O(7) bond length is 2.26 Å. The Y(3)-O(8) bond length is 2.20 Å. The Y(3)-O(9) bond length is 2.30 Å. In the fourth Y site, Y(4) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), one O(5), and one O(6) atom. The Y(4)-O(1) bond length is 2.44 Å. The Y(4)-O(2) bond length is 2.38 Å. The Y(4)-O(3) bond length is 2.47 Å. The Y(4)-O(4) bond length is 2.29 Å. The Y(4)-O(5) bond length is 2.22 Å. The Y(4)-O(6) bond length is 2.29 Å. There are nine inequivalent O sites. In the first O site, O(1) is bonded in a 4-coordinate geometry to one Ba(3), one Y(1), one Y(2), and one Y(4) atom. In the second O site, O(2) is bonded in a 4-coordinate geometry to one Ba(3), one Y(1), one Y(2), and one Y(4) atom. In the third O site, O(3) is bonded in a 4-coordinate geometry to one Ba(3), one Y(1), one Y(2), and one Y(4) atom. In the fourth O site, O(4) is bonded in a distorted see-saw-like geometry to one Ba(2), one Y(2), one Y(3), and one Y(4) atom. In the fifth O site, O(5) is bonded in a distorted see-saw-like geometry to one Ba(2), one Y(2), one Y(3), and one Y(4) atom. In the sixth O site, O(6) is bonded in a 4-coordinate geometry to one Ba(2), one Y(2), one Y(3), and one Y(4) atom. In the seventh O site, O(7) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Y(1), and one Y(3) atom. In the eighth O site, O(8) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Y(1), and one Y(3) atom. In the ninth O site, O(9) is bonded in a 5-coordinate geometry to one Ba(1), one Ba(2), one Ba(3), one Y(1), and one Y(3) atom.