Preparation and X-ray powder diffraction patterns of the sodium vanadates NaVO3, Na4V2O7, and Na3VO4
The reactions of various sodium oxo-compounds with vanadium pentoxide and sodium metavanadate are described. Products of reaction are characterised by means of thermal gravimetric analysis, differential thermal analysis, and powder X-ray crystallography. Sodium metavanadate. NaVO3, and sodium pyrovanadate, Na4V2O7, are found to possess two temperature-dependent structural modifications, whilst four structural modifications of the orthovanadate, Na3VO4, are obtained depending on the method of preparation.