Preparation and characterisation of the compounds sodium tetraoxoniobate(V) Na3NbO4 and sodium tetraoxotantalate(V) Na3TaO4
Abstract
The preparation is described of two forms of the ternary oxide Na3TaO4 which are analogous to cubic and monoclinic forms of the compound Na3NbO4. A third orthorhombic form of each compound has been prepared by the reaction of sodium oxide with the transition metal under controlled conditions. The cubic form of the compound Na3TaO4 has been prepared as a single phase and the relationship of this phase to the monoclinic and orthorhombic forms is discussed.