H4OTa2O6 crystallizes in the monoclinic Cc space group. The structure consists of four water molecules inside a HTaO3 framework. In the HTaO3 framework, there are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(3) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 33-49°. In the second Ta site, Ta(2) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(4) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 33-49°. There are two inequivalent H sites. In the first H site, H(3) is bonded in a single-bond geometry to one O(6) atom. In the second H site, H(4) is bonded in a single-bond geometry to one O(3) atom. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ta(1) and one Ta(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ta(1) and one Ta(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Ta(1) and one H(4) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Ta(2) atoms. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ta(1) and one Ta(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ta(1), one Ta(2), and one H(3) atom.
H4OTa2O6 crystallizes in the monoclinic Cc space group. The structure consists of four water molecules inside a HTaO3 framework. In the HTaO3 framework, there are two inequivalent Ta sites. In the first Ta site, Ta(1) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(3) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 33-49°. The Ta(1)-O(1) bond length is 1.89 Å. The Ta(1)-O(2) bond length is 1.96 Å. The Ta(1)-O(5) bond length is 1.89 Å. The Ta(1)-O(6) bond length is 2.13 Å. There is one shorter (2.04 Å) and one longer (2.20 Å) Ta(1)-O(3) bond length. In the second Ta site, Ta(2) is bonded to one O(1), one O(2), one O(5), one O(6), and two equivalent O(4) atoms to form corner-sharing TaO6 octahedra. The corner-sharing octahedral tilt angles range from 33-49°. The Ta(2)-O(1) bond length is 2.02 Å. The Ta(2)-O(2) bond length is 1.94 Å. The Ta(2)-O(5) bond length is 1.97 Å. The Ta(2)-O(6) bond length is 2.15 Å. There is one shorter (1.91 Å) and one longer (2.01 Å) Ta(2)-O(4) bond length. There are two inequivalent H sites. In the first H site, H(3) is bonded in a single-bond geometry to one O(6) atom. The H(3)-O(6) bond length is 0.99 Å. In the second H site, H(4) is bonded in a single-bond geometry to one O(3) atom. The H(4)-O(3) bond length is 1.00 Å. There are six inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to one Ta(1) and one Ta(2) atom. In the second O site, O(2) is bonded in a bent 150 degrees geometry to one Ta(1) and one Ta(2) atom. In the third O site, O(3) is bonded in a distorted single-bond geometry to two equivalent Ta(1) and one H(4) atom. In the fourth O site, O(4) is bonded in a bent 150 degrees geometry to two equivalent Ta(2) atoms. In the fifth O site, O(5) is bonded in a bent 150 degrees geometry to one Ta(1) and one Ta(2) atom. In the sixth O site, O(6) is bonded in a distorted single-bond geometry to one Ta(1), one Ta(2), and one H(3) atom.