HTiNbO5 crystallizes in the orthorhombic Pnma space group. Ti(1) is bonded to one O(1), one O(2), one O(5), and three equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 31°. Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms. H(1) is bonded in a linear geometry to one O(1) and one O(4) atom. There are five inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ti(1), one Nb(1), and one H(1) atom. In the second O site, O(2) is bonded in a linear geometry to one Ti(1) and one Nb(1) atom. In the third O site, O(3) is bonded to three equivalent Ti(1) and one Nb(1) atom to form a mixture of distorted corner and edge-sharing OTi3Nb trigonal pyramids. In the fourth O site, O(4) is bonded in a linear geometry to one Nb(1) and one H(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ti(1) and two equivalent Nb(1) atoms.
HTiNbO5 crystallizes in the orthorhombic Pnma space group. Ti(1) is bonded to one O(1), one O(2), one O(5), and three equivalent O(3) atoms to form a mixture of distorted corner and edge-sharing TiO6 octahedra. The corner-sharing octahedral tilt angles are 31°. The Ti(1)-O(1) bond length is 1.95 Å. The Ti(1)-O(2) bond length is 1.77 Å. The Ti(1)-O(5) bond length is 2.11 Å. There are two shorter (1.98 Å) and one longer (2.23 Å) Ti(1)-O(3) bond length. Nb(1) is bonded in a 6-coordinate geometry to one O(1), one O(2), one O(3), one O(4), and two equivalent O(5) atoms. The Nb(1)-O(1) bond length is 2.12 Å. The Nb(1)-O(2) bond length is 2.00 Å. The Nb(1)-O(3) bond length is 2.42 Å. The Nb(1)-O(4) bond length is 1.76 Å. Both Nb(1)-O(5) bond lengths are 2.01 Å. H(1) is bonded in a linear geometry to one O(1) and one O(4) atom. The H(1)-O(1) bond length is 1.03 Å. The H(1)-O(4) bond length is 1.55 Å. There are five inequivalent O sites. In the first O site, O(1) is bonded in a trigonal planar geometry to one Ti(1), one Nb(1), and one H(1) atom. In the second O site, O(2) is bonded in a linear geometry to one Ti(1) and one Nb(1) atom. In the third O site, O(3) is bonded to three equivalent Ti(1) and one Nb(1) atom to form a mixture of distorted corner and edge-sharing OTi3Nb trigonal pyramids. In the fourth O site, O(4) is bonded in a linear geometry to one Nb(1) and one H(1) atom. In the fifth O site, O(5) is bonded in a distorted trigonal planar geometry to one Ti(1) and two equivalent Nb(1) atoms.