The crystal structure of cubic hydrogen tungsten bronze

Abstract

The structure of D 0.53WO 3 has been determined by a room temperature powder neutron diffraction study. The unit cell is body centered cubic ( Im3) and contains 8 formula weights ( a = 7.562 ± 0.002 Å). The average cell content was refined by a least squares method based on peak intensities. The tungsten atoms lie on the special sites of the perovskite structure and are surrounded by nearly regular octahedrons of oxygen atoms with the latter displaced from the normal perovskite positions along 〈110〉. The deuterium atoms constitute statistically distributed -OD bonds which are directed towards the nearest oxygen atom of a neighboring octahedron. The analogous hydrogen compound is best described as a nonstoichiometric oxide hydroxide WO 3− x (OH) x based on a distorted ReO 3 structure. The crystal structure is closely related to that of In(OH) 3 and Sc(OH) 3.