FeTaO4 is Hydrophilite-derived structured and crystallizes in the monoclinic Cm space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with four equivalent Ta(2)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-51°. In the second Ta site, Ta(2) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms to form TaO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-51°. There are two inequivalent Fe sites. In the first Fe site, Fe(1) 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 four equivalent Ta(2)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-50°. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, and edges with two equivalent Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-50°. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ta(2), one Fe(1), and one Fe(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ta(1), one Fe(1), and one Fe(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ta(2), one Fe(1), and one Fe(2) atom.
FeTaO4 is Hydrophilite-derived structured and crystallizes in the monoclinic Cm space group. There are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), one O(3), two equivalent O(2), and two equivalent O(5) atoms to form TaO6 octahedra that share corners with four equivalent Ta(2)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Fe(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-51°. The Ta(1)-O(1) bond length is 1.99 Å. The Ta(1)-O(3) bond length is 2.02 Å. Both Ta(1)-O(2) bond lengths are 2.02 Å. Both Ta(1)-O(5) bond lengths are 1.95 Å. In the second Ta site, Ta(2) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(2) atoms to form TaO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, and edges with two equivalent Fe(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-51°. The Ta(2)-O(1) bond length is 2.05 Å. The Ta(2)-O(3) bond length is 2.01 Å. The Ta(2)-O(4) bond length is 1.96 Å. The Ta(2)-O(6) bond length is 1.91 Å. Both Ta(2)-O(2) bond lengths are 2.00 Å. There are two inequivalent Fe sites. In the first Fe site, Fe(1) 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 four equivalent Ta(2)O6 octahedra, corners with four equivalent Fe(2)O6 octahedra, and edges with two equivalent Ta(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-50°. The Fe(1)-O(4) bond length is 1.96 Å. The Fe(1)-O(6) bond length is 2.03 Å. Both Fe(1)-O(2) bond lengths are 2.05 Å. Both Fe(1)-O(5) bond lengths are 2.02 Å. In the second Fe site, Fe(2) is bonded to one O(1), one O(3), one O(4), one O(6), and two equivalent O(5) atoms to form FeO6 octahedra that share corners with four equivalent Ta(1)O6 octahedra, corners with four equivalent Fe(1)O6 octahedra, and edges with two equivalent Ta(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-50°. The Fe(2)-O(1) bond length is 2.02 Å. The Fe(2)-O(3) bond length is 2.04 Å. The Fe(2)-O(4) bond length is 2.02 Å. The Fe(2)-O(6) bond length is 2.06 Å. Both Fe(2)-O(5) bond lengths are 1.99 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(2) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(1) atom. In the third O site, O(3) is bonded in a trigonal planar geometry to one Ta(1), one Ta(2), and one Fe(2) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ta(2), one Fe(1), and one Fe(2) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ta(1), one Fe(1), and one Fe(2) atom. In the sixth O site, O(6) is bonded in a distorted trigonal planar geometry to one Ta(2), one Fe(1), and one Fe(2) atom.