CATION NONSTOICHIOMETRY OF THE BACUO2+X PHASE

This note presents evidence for cation non-stoichiometry of the BaCuO2 phase in samples prepared from starting materials with and without ca rbonate. Phase equilibrium experiments using polycrystalline samples a s well as quantitative energy dispersive X-ray spectrometric analysis (EDS) of a BaCuO2 single crystal grown from a Ba-Cu-O melt were comple ted. Results showed this phase to be relatively copper rich with a nom inal composition of Ba0.94Cu1.06O2+x. A brief literature review of the compositional and structural investigations of the BaCuO2 phase is al so given.