Ba4Y2Fe2O11 crystallizes in the orthorhombic Pmc2_1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(2), one O(4), one O(5), one O(6), one O(7), two equivalent O(8), and three equivalent O(3) atoms. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(4), one O(6), one O(7), two equivalent O(1), two equivalent O(9), and three equivalent O(2) atoms. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form YO6 octahedra that share corners with two equivalent Y(1)O6 octahedra, corners with two equivalent Fe(1)O5 square pyramids, and corners with two equivalent Fe(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 14°. In the second Y site, Y(2) is bonded to one O(6), one O(7), two equivalent O(3), and two equivalent O(8) atoms to form YO6 octahedra that share corners with two equivalent Y(2)O6 octahedra, corners with two equivalent Fe(1)O5 square pyramids, and corners with two equivalent Fe(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 15°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(6), one O(7), one O(9), and two equivalent O(2) atoms to form distorted FeO5 square pyramids that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-10°. In the second Fe site, Fe(2) is bonded to one O(4), one O(5), and two equivalent O(3) atoms to form distorted FeO4 tetrahedra that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-37°. There are nine inequivalent O sites. In the first O site, O(7) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(2), and one Fe(1) atom. In the second O site, O(8) is bonded in a 6-coordinate geometry to four equivalent Ba(1) and two equivalent Y(2) atoms. In the third O site, O(9) is bonded in a distorted single-bond geometry to four equivalent Ba(2) and one Fe(1) atom. In the fourth O site, O(1) is bonded in a 6-coordinate geometry to four equivalent Ba(2) and two equivalent Y(1) atoms. In the fifth O site, O(2) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), one Y(1), and one Fe(1) atom. In the sixth O site, O(3) is bonded in a 5-coordinate geometry to three equivalent Ba(1), one Y(2), and one Fe(2) atom. In the seventh O site, O(4) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(1), and one Fe(2) atom. In the eighth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Y(1), and one Fe(2) atom. In the ninth O site, O(6) is bonded in a distorted octahedral geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(2), and one Fe(1) atom.
Ba4Y2Fe2O11 crystallizes in the orthorhombic Pmc2_1 space group. There are two inequivalent Ba sites. In the first Ba site, Ba(1) is bonded in a 10-coordinate geometry to one O(2), one O(4), one O(5), one O(6), one O(7), two equivalent O(8), and three equivalent O(3) atoms. The Ba(1)-O(2) bond length is 2.96 Å. The Ba(1)-O(4) bond length is 3.07 Å. The Ba(1)-O(5) bond length is 2.73 Å. The Ba(1)-O(6) bond length is 2.78 Å. The Ba(1)-O(7) bond length is 2.98 Å. There is one shorter (2.77 Å) and one longer (3.20 Å) Ba(1)-O(8) bond length. There are a spread of Ba(1)-O(3) bond distances ranging from 2.95-3.16 Å. In the second Ba site, Ba(2) is bonded in a 10-coordinate geometry to one O(4), one O(6), one O(7), two equivalent O(1), two equivalent O(9), and three equivalent O(2) atoms. The Ba(2)-O(4) bond length is 3.14 Å. The Ba(2)-O(6) bond length is 3.05 Å. The Ba(2)-O(7) bond length is 2.95 Å. There is one shorter (2.84 Å) and one longer (3.19 Å) Ba(2)-O(1) bond length. There is one shorter (2.75 Å) and one longer (2.83 Å) Ba(2)-O(9) bond length. There are a spread of Ba(2)-O(2) bond distances ranging from 2.90-3.15 Å. There are two inequivalent Y sites. In the first Y site, Y(1) is bonded to one O(4), one O(5), two equivalent O(1), and two equivalent O(2) atoms to form YO6 octahedra that share corners with two equivalent Y(1)O6 octahedra, corners with two equivalent Fe(1)O5 square pyramids, and corners with two equivalent Fe(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 14°. The Y(1)-O(4) bond length is 2.34 Å. The Y(1)-O(5) bond length is 2.34 Å. Both Y(1)-O(1) bond lengths are 2.19 Å. Both Y(1)-O(2) bond lengths are 2.24 Å. In the second Y site, Y(2) is bonded to one O(6), one O(7), two equivalent O(3), and two equivalent O(8) atoms to form YO6 octahedra that share corners with two equivalent Y(2)O6 octahedra, corners with two equivalent Fe(1)O5 square pyramids, and corners with two equivalent Fe(2)O4 tetrahedra. The corner-sharing octahedral tilt angles are 15°. The Y(2)-O(6) bond length is 2.24 Å. The Y(2)-O(7) bond length is 2.27 Å. Both Y(2)-O(3) bond lengths are 2.42 Å. There is one shorter (2.19 Å) and one longer (2.21 Å) Y(2)-O(8) bond length. There are two inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to one O(6), one O(7), one O(9), and two equivalent O(2) atoms to form distorted FeO5 square pyramids that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-10°. The Fe(1)-O(6) bond length is 2.02 Å. The Fe(1)-O(7) bond length is 1.95 Å. The Fe(1)-O(9) bond length is 1.88 Å. Both Fe(1)-O(2) bond lengths are 1.89 Å. In the second Fe site, Fe(2) is bonded to one O(4), one O(5), and two equivalent O(3) atoms to form distorted FeO4 tetrahedra that share corners with two equivalent Y(1)O6 octahedra and corners with two equivalent Y(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 4-37°. The Fe(2)-O(4) bond length is 1.83 Å. The Fe(2)-O(5) bond length is 1.83 Å. Both Fe(2)-O(3) bond lengths are 1.84 Å. There are nine inequivalent O sites. In the first O site, O(7) is bonded in a 6-coordinate geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(2), and one Fe(1) atom. In the second O site, O(8) is bonded in a 6-coordinate geometry to four equivalent Ba(1) and two equivalent Y(2) atoms. In the third O site, O(9) is bonded in a distorted single-bond geometry to four equivalent Ba(2) and one Fe(1) atom. In the fourth O site, O(1) is bonded in a 6-coordinate geometry to four equivalent Ba(2) and two equivalent Y(1) atoms. In the fifth O site, O(2) is bonded in a distorted linear geometry to one Ba(1), three equivalent Ba(2), one Y(1), and one Fe(1) atom. In the sixth O site, O(3) is bonded in a 5-coordinate geometry to three equivalent Ba(1), one Y(2), and one Fe(2) atom. In the seventh O site, O(4) is bonded in a distorted linear geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(1), and one Fe(2) atom. In the eighth O site, O(5) is bonded in a 4-coordinate geometry to two equivalent Ba(1), one Y(1), and one Fe(2) atom. In the ninth O site, O(6) is bonded in a distorted octahedral geometry to two equivalent Ba(1), two equivalent Ba(2), one Y(2), and one Fe(1) atom.