FeTaO4 is Hydrophilite-derived structured and crystallizes in the tetragonal I4_1md space group. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. In the second Ta site, Ta(2) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-51°. In the third Ta site, Ta(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-51°. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  an edgeedge with one Ta(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-53°. In the second Fe site, Fe(2) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. In the third Fe site, Fe(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. There are six inequivalent O sites. In the first O site, O(6) is bonded in a distorted trigonal planar geometry to one Ta(2), one Ta(3), and one Fe(1) atom. In the second O site, O(1) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(1) atom. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Ta(3), one Fe(1), and one Fe(3) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to one Ta(3), one Fe(2), and one Fe(3) atom. In the fifth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ta(1), one Fe(2), and one Fe(3) atom. In the sixth O site, O(5) is bonded in a trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(2) atom.
FeTaO4 is Hydrophilite-derived structured and crystallizes in the tetragonal I4_1md space group. There are three inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to two equivalent O(1), two equivalent O(4), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. Both Ta(1)-O(1) bond lengths are 2.03 Å. Both Ta(1)-O(4) bond lengths are 1.91 Å. Both Ta(1)-O(5) bond lengths are 2.10 Å. In the second Ta site, Ta(2) is bonded to two equivalent O(1), two equivalent O(5), and two equivalent O(6) atoms to form TaO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-51°. Both Ta(2)-O(1) bond lengths are 2.02 Å. Both Ta(2)-O(5) bond lengths are 1.98 Å. Both Ta(2)-O(6) bond lengths are 2.01 Å. In the third Ta site, Ta(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(6) atoms to form TaO6 octahedra that share corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Fe(1)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-51°. Both Ta(3)-O(2) bond lengths are 1.93 Å. Both Ta(3)-O(3) bond lengths are 2.01 Å. Both Ta(3)-O(6) bond lengths are 2.09 Å. There are three inequivalent Fe sites. In the first Fe site, Fe(1) is bonded to two equivalent O(1), two equivalent O(2), and two equivalent O(6) atoms to form FeO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(2)O6 octahedra, and  an edgeedge with one Ta(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 44-53°. Both Fe(1)-O(1) bond lengths are 2.09 Å. Both Fe(1)-O(2) bond lengths are 2.02 Å. Both Fe(1)-O(6) bond lengths are 2.03 Å. In the second Fe site, Fe(2) is bonded to two equivalent O(3), two equivalent O(4), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(2)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Fe(3)O6 octahedra,  an edgeedge with one Ta(1)O6 octahedra, and  an edgeedge with one Fe(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-54°. Both Fe(2)-O(3) bond lengths are 1.99 Å. Both Fe(2)-O(4) bond lengths are 2.10 Å. Both Fe(2)-O(5) bond lengths are 2.07 Å. In the third Fe site, Fe(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(4) atoms to form FeO6 octahedra that share corners with two equivalent Ta(1)O6 octahedra, corners with two equivalent Ta(3)O6 octahedra, corners with two equivalent Fe(1)O6 octahedra, corners with two equivalent Fe(2)O6 octahedra,  an edgeedge with one Ta(3)O6 octahedra, and  an edgeedge with one Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 45-53°. Both Fe(3)-O(2) bond lengths are 2.09 Å. Both Fe(3)-O(3) bond lengths are 2.01 Å. Both Fe(3)-O(4) bond lengths are 2.04 Å. There are six inequivalent O sites. In the first O site, O(6) is bonded in a distorted trigonal planar geometry to one Ta(2), one Ta(3), and one Fe(1) atom. In the second O site, O(1) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(1) atom. In the third O site, O(2) is bonded in a distorted trigonal planar geometry to one Ta(3), one Fe(1), and one Fe(3) atom. In the fourth O site, O(3) is bonded in a distorted trigonal planar geometry to one Ta(3), one Fe(2), and one Fe(3) atom. In the fifth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ta(1), one Fe(2), and one Fe(3) atom. In the sixth O site, O(5) is bonded in a trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(2) atom.