Fe2TiO4 crystallizes in the orthorhombic Pmma space group. Ti(1) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(6) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with three equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-51°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(5) atoms. In the second Fe site, Fe(2) is bonded in a 6-coordinate geometry to two equivalent O(4) and four equivalent O(6) atoms. In the third Fe site, Fe(3) is bonded to one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with three equivalent Fe(3)O6 octahedra, edges with two equivalent Ti(1)O6 octahedra, and edges with three equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-55°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a square co-planar geometry to four equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a square co-planar geometry to four equivalent Fe(3) atoms. In the third O site, O(3) is bonded to two equivalent Ti(1) and two equivalent Fe(1) atoms to form distorted OTi2Fe2 tetrahedra that share corners with four equivalent O(6)Ti2Fe3 square pyramids, corners with two equivalent O(3)Ti2Fe2 tetrahedra, corners with six equivalent O(5)TiFe4 trigonal bipyramids, and edges with two equivalent O(5)TiFe4 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Fe(2) and two equivalent Fe(3) atoms to form OFe4 tetrahedra that share corners with six equivalent O(6)Ti2Fe3 square pyramids, corners with two equivalent O(4)Fe4 tetrahedra, corners with four equivalent O(5)TiFe4 trigonal bipyramids, and edges with two equivalent O(6)Ti2Fe3 square pyramids. In the fifth O site, O(5) is bonded to one Ti(1), two equivalent Fe(1), and two equivalent Fe(3) atoms to form distorted OTiFe4 trigonal bipyramids that share corners with two equivalent O(4)Fe4 tetrahedra, corners with three equivalent O(3)Ti2Fe2 tetrahedra, corners with two equivalent O(5)TiFe4 trigonal bipyramids, edges with two equivalent O(6)Ti2Fe3 square pyramids,  an edgeedge with one O(3)Ti2Fe2 tetrahedra, and edges with three equivalent O(5)TiFe4 trigonal bipyramids. In the sixth O site, O(6) is bonded to two equivalent Ti(1), one Fe(3), and two equivalent Fe(2) atoms to form distorted OTi2Fe3 square pyramids that share corners with two equivalent O(6)Ti2Fe3 square pyramids, corners with two equivalent O(3)Ti2Fe2 tetrahedra, corners with three equivalent O(4)Fe4 tetrahedra, edges with three equivalent O(6)Ti2Fe3 square pyramids,  an edgeedge with one O(4)Fe4 tetrahedra, and edges with two equivalent O(5)TiFe4 trigonal bipyramids.
Fe2TiO4 crystallizes in the orthorhombic Pmma space group. Ti(1) is bonded to one O(3), one O(5), two equivalent O(1), and two equivalent O(6) atoms to form TiO6 octahedra that share corners with three equivalent Ti(1)O6 octahedra, edges with two equivalent Fe(3)O6 octahedra, and edges with three equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-51°. The Ti(1)-O(3) bond length is 1.99 Å. The Ti(1)-O(5) bond length is 1.96 Å. Both Ti(1)-O(1) bond lengths are 2.08 Å. Both Ti(1)-O(6) bond lengths are 2.00 Å. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded in a 6-coordinate geometry to two equivalent O(3) and four equivalent O(5) atoms. Both Fe(1)-O(3) bond lengths are 2.23 Å. All Fe(1)-O(5) bond lengths are 2.20 Å. In the second Fe site, Fe(2) is bonded in a 6-coordinate geometry to two equivalent O(4) and four equivalent O(6) atoms. Both Fe(2)-O(4) bond lengths are 2.06 Å. All Fe(2)-O(6) bond lengths are 2.39 Å. In the third Fe site, Fe(3) is bonded to one O(4), one O(6), two equivalent O(2), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with three equivalent Fe(3)O6 octahedra, edges with two equivalent Ti(1)O6 octahedra, and edges with three equivalent Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 0-55°. The Fe(3)-O(4) bond length is 1.97 Å. The Fe(3)-O(6) bond length is 2.20 Å. Both Fe(3)-O(2) bond lengths are 2.08 Å. Both Fe(3)-O(5) bond lengths are 2.22 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a square co-planar geometry to four equivalent Ti(1) atoms. In the second O site, O(2) is bonded in a square co-planar geometry to four equivalent Fe(3) atoms. In the third O site, O(3) is bonded to two equivalent Ti(1) and two equivalent Fe(1) atoms to form distorted OTi2Fe2 tetrahedra that share corners with four equivalent O(6)Ti2Fe3 square pyramids, corners with two equivalent O(3)Ti2Fe2 tetrahedra, corners with six equivalent O(5)TiFe4 trigonal bipyramids, and edges with two equivalent O(5)TiFe4 trigonal bipyramids. In the fourth O site, O(4) is bonded to two equivalent Fe(2) and two equivalent Fe(3) atoms to form OFe4 tetrahedra that share corners with six equivalent O(6)Ti2Fe3 square pyramids, corners with two equivalent O(4)Fe4 tetrahedra, corners with four equivalent O(5)TiFe4 trigonal bipyramids, and edges with two equivalent O(6)Ti2Fe3 square pyramids. In the fifth O site, O(5) is bonded to one Ti(1), two equivalent Fe(1), and two equivalent Fe(3) atoms to form distorted OTiFe4 trigonal bipyramids that share corners with two equivalent O(4)Fe4 tetrahedra, corners with three equivalent O(3)Ti2Fe2 tetrahedra, corners with two equivalent O(5)TiFe4 trigonal bipyramids, edges with two equivalent O(6)Ti2Fe3 square pyramids,  an edgeedge with one O(3)Ti2Fe2 tetrahedra, and edges with three equivalent O(5)TiFe4 trigonal bipyramids. In the sixth O site, O(6) is bonded to two equivalent Ti(1), one Fe(3), and two equivalent Fe(2) atoms to form distorted OTi2Fe3 square pyramids that share corners with two equivalent O(6)Ti2Fe3 square pyramids, corners with two equivalent O(3)Ti2Fe2 tetrahedra, corners with three equivalent O(4)Fe4 tetrahedra, edges with three equivalent O(6)Ti2Fe3 square pyramids,  an edgeedge with one O(4)Fe4 tetrahedra, and edges with two equivalent O(5)TiFe4 trigonal bipyramids.