Al(FeO2)3 is beta indium sulfide-derived structured and crystallizes in the trigonal P-3m1 space group. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1) and four equivalent O(4) atoms to form FeO6 octahedra that share corners with four equivalent Al(2)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share  a cornercorner with one Al(2)O4 tetrahedra, corners with three equivalent Al(1)O4 tetrahedra,  an edgeedge with one Fe(3)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and edges with four equivalent Fe(2)O6 octahedra. In the third Fe site, Fe(3) is bonded to three equivalent O(4) and three equivalent O(6) atoms to form FeO6 octahedra that share corners with three equivalent Al(2)O4 tetrahedra, edges with three equivalent Fe(1)O6 octahedra, and edges with three equivalent Fe(2)O6 octahedra. In the fourth Fe site, Fe(4) is bonded to six equivalent O(5) atoms to form FeO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra and edges with six equivalent Fe(2)O6 octahedra. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2) and three equivalent O(5) atoms to form AlO4 tetrahedra that share corners with three equivalent Fe(4)O6 octahedra and corners with nine equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-58°. In the second Al site, Al(2) is bonded to one O(3) and three equivalent O(4) atoms to form AlO4 tetrahedra that share corners with three equivalent Fe(2)O6 octahedra, corners with three equivalent Fe(3)O6 octahedra, and corners with six equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-58°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to three equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to three equivalent Fe(2) and one Al(1) atom. In the third O site, O(3) is bonded in a distorted trigonal pyramidal geometry to three equivalent Fe(2) and one Al(2) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Fe(3), two equivalent Fe(1), and one Al(2) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Fe(4), two equivalent Fe(2), and one Al(1) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Fe(3) and two equivalent Fe(2) atoms.
Al(FeO2)3 is beta indium sulfide-derived structured and crystallizes in the trigonal P-3m1 space group. There are four inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1) and four equivalent O(4) atoms to form FeO6 octahedra that share corners with four equivalent Al(2)O4 tetrahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with four equivalent Fe(1)O6 octahedra. Both Fe(1)-O(1) bond lengths are 1.93 Å. All Fe(1)-O(4) bond lengths are 2.13 Å. In the second Fe site, Fe(2) is bonded to one O(2), one O(3), two equivalent O(5), and two equivalent O(6) atoms to form FeO6 octahedra that share  a cornercorner with one Al(2)O4 tetrahedra, corners with three equivalent Al(1)O4 tetrahedra,  an edgeedge with one Fe(3)O6 octahedra,  an edgeedge with one Fe(4)O6 octahedra, and edges with four equivalent Fe(2)O6 octahedra. The Fe(2)-O(2) bond length is 2.15 Å. The Fe(2)-O(3) bond length is 2.07 Å. Both Fe(2)-O(5) bond lengths are 2.12 Å. Both Fe(2)-O(6) bond lengths are 1.93 Å. In the third Fe site, Fe(3) is bonded to three equivalent O(4) and three equivalent O(6) atoms to form FeO6 octahedra that share corners with three equivalent Al(2)O4 tetrahedra, edges with three equivalent Fe(1)O6 octahedra, and edges with three equivalent Fe(2)O6 octahedra. All Fe(3)-O(4) bond lengths are 2.12 Å. All Fe(3)-O(6) bond lengths are 2.00 Å. In the fourth Fe site, Fe(4) is bonded to six equivalent O(5) atoms to form FeO6 octahedra that share corners with six equivalent Al(1)O4 tetrahedra and edges with six equivalent Fe(2)O6 octahedra. All Fe(4)-O(5) bond lengths are 2.06 Å. There are two inequivalent Al sites. In the first Al site, Al(1) is bonded to one O(2) and three equivalent O(5) atoms to form AlO4 tetrahedra that share corners with three equivalent Fe(4)O6 octahedra and corners with nine equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 52-58°. The Al(1)-O(2) bond length is 1.81 Å. All Al(1)-O(5) bond lengths are 1.84 Å. In the second Al site, Al(2) is bonded to one O(3) and three equivalent O(4) atoms to form AlO4 tetrahedra that share corners with three equivalent Fe(2)O6 octahedra, corners with three equivalent Fe(3)O6 octahedra, and corners with six equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 55-58°. The Al(2)-O(3) bond length is 1.84 Å. All Al(2)-O(4) bond lengths are 1.84 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a trigonal non-coplanar geometry to three equivalent Fe(1) atoms. In the second O site, O(2) is bonded in a rectangular see-saw-like geometry to three equivalent Fe(2) and one Al(1) atom. In the third O site, O(3) is bonded in a distorted trigonal pyramidal geometry to three equivalent Fe(2) and one Al(2) atom. In the fourth O site, O(4) is bonded in a rectangular see-saw-like geometry to one Fe(3), two equivalent Fe(1), and one Al(2) atom. In the fifth O site, O(5) is bonded in a rectangular see-saw-like geometry to one Fe(4), two equivalent Fe(2), and one Al(1) atom. In the sixth O site, O(6) is bonded in a distorted T-shaped geometry to one Fe(3) and two equivalent Fe(2) atoms.