Preparation and studies of a new ammonium vanadium bronze, (NH<inf>4</inf>)<inf>x</inf>V<inf>2</inf>O<inf>5</inf>

A new bronze-type phase of composition (NH4)0.40±0.02V2O5 is obtained around 230°C during the thermal decomposition of NH4VO3 in hydrogen atmosphere. The bronze intermediate is characterized by X-ray diffraction, electrical conductivity, magnetic susceptibility, and ESR studies. It is found to be isostructural with other known β-type vanadium bronzes of general formula MxV2O5, where M is usually a monovalent metal. Electrical conductivity and magnetic studies indicate the localized character of conduction electrons at V+4 sites. At high temperatures (>400°C), the bronze undergoes decomposition and subsequent reduction to V2O3 in hydrogen atmosphere. © 1974.