H2W2O7 crystallizes in the tetragonal I4_1/amd space group. The structure consists of four water molecules inside a WO3 framework. In the WO3 framework, W(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedral tilt angles range from 35-38°. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent W(1) atoms. In the second O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent W(1) atoms.
H2W2O7 crystallizes in the tetragonal I4_1/amd space group. The structure consists of four water molecules inside a WO3 framework. In the WO3 framework, W(1) is bonded to two equivalent O(1) and four equivalent O(2) atoms to form corner-sharing WO6 octahedra. The corner-sharing octahedral tilt angles range from 35-38°. Both W(1)-O(1) bond lengths are 1.95 Å. All W(1)-O(2) bond lengths are 1.93 Å. There are two inequivalent O sites. In the first O site, O(1) is bonded in a bent 150 degrees geometry to two equivalent W(1) atoms. In the second O site, O(2) is bonded in a bent 150 degrees geometry to two equivalent W(1) atoms.