Ti5NbO12 is Rutile-derived structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent Ti(3)O6 octahedra, corners with five equivalent Ti(2)O6 octahedra,  an edgeedge with one Ti(1)O6 octahedra, and  an edgeedge with one Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-52°. In the second Ti site, Ti(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with three equivalent Nb(1)O6 octahedra, corners with five equivalent Ti(1)O6 octahedra,  an edgeedge with one Ti(2)O6 octahedra, and  an edgeedge with one Ti(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-52°. In the third Ti site, Ti(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with six equivalent Ti(1)O6 octahedra, and edges with two equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-49°. Nb(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Ti(3)O6 octahedra, corners with six equivalent Ti(2)O6 octahedra, and edges with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ti(2), and one Nb(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ti(1), one Ti(2), and one Ti(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ti(2), one Ti(3), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ti(1) and two equivalent Ti(2) atoms. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ti(3) and two equivalent Ti(1) atoms.
Ti5NbO12 is Rutile-derived structured and crystallizes in the monoclinic C2/m space group. There are three inequivalent Ti sites. In the first Ti site, Ti(1) is bonded to one O(2), one O(4), two equivalent O(1), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with three equivalent Ti(3)O6 octahedra, corners with five equivalent Ti(2)O6 octahedra,  an edgeedge with one Ti(1)O6 octahedra, and  an edgeedge with one Nb(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-52°. The Ti(1)-O(2) bond length is 2.01 Å. The Ti(1)-O(4) bond length is 2.04 Å. Both Ti(1)-O(1) bond lengths are 2.01 Å. Both Ti(1)-O(5) bond lengths are 1.95 Å. In the second Ti site, Ti(2) is bonded to one O(2), one O(3), two equivalent O(1), and two equivalent O(4) atoms to form TiO6 octahedra that share corners with three equivalent Nb(1)O6 octahedra, corners with five equivalent Ti(1)O6 octahedra,  an edgeedge with one Ti(2)O6 octahedra, and  an edgeedge with one Ti(3)O6 octahedra. The corner-sharing octahedral tilt angles range from 46-52°. The Ti(2)-O(2) bond length is 1.96 Å. The Ti(2)-O(3) bond length is 2.02 Å. Both Ti(2)-O(1) bond lengths are 2.02 Å. There is one shorter (1.93 Å) and one longer (2.00 Å) Ti(2)-O(4) bond length. In the third Ti site, Ti(3) is bonded to two equivalent O(2), two equivalent O(3), and two equivalent O(5) atoms to form TiO6 octahedra that share corners with two equivalent Nb(1)O6 octahedra, corners with six equivalent Ti(1)O6 octahedra, and edges with two equivalent Ti(2)O6 octahedra. The corner-sharing octahedral tilt angles range from 47-49°. Both Ti(3)-O(2) bond lengths are 1.98 Å. Both Ti(3)-O(3) bond lengths are 1.97 Å. Both Ti(3)-O(5) bond lengths are 2.03 Å. Nb(1) is bonded to two equivalent O(3) and four equivalent O(1) atoms to form NbO6 octahedra that share corners with two equivalent Ti(3)O6 octahedra, corners with six equivalent Ti(2)O6 octahedra, and edges with two equivalent Ti(1)O6 octahedra. The corner-sharing octahedral tilt angles range from 49-50°. Both Nb(1)-O(3) bond lengths are 2.04 Å. All Nb(1)-O(1) bond lengths are 2.01 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a distorted trigonal planar geometry to one Ti(1), one Ti(2), and one Nb(1) atom. In the second O site, O(2) is bonded in a trigonal planar geometry to one Ti(1), one Ti(2), and one Ti(3) atom. In the third O site, O(3) is bonded in a distorted trigonal planar geometry to one Ti(2), one Ti(3), and one Nb(1) atom. In the fourth O site, O(4) is bonded in a distorted trigonal planar geometry to one Ti(1) and two equivalent Ti(2) atoms. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ti(3) and two equivalent Ti(1) atoms.