STUDY OF FLUORINE INCORPORATION INTO YBA2CU3O6.5-RAY PHOTOELECTRON-SPECTROSCOPY(DELTA BY X)

Earlier, the study of fluorine incorporation into the lattice of YBa2C u3O6.5+delta by X-ray emission spectroscopy using F K alpha and O K al pha was reported. In this communication recent XPS studies on these fl uorine-containing Y-123 oxides are ionized. These data fend further su pport to the conclusions drawn earlier from X-ray emission spectroscop ic studies, It is seen from XPS data that there is a significant chemi cal shift of fluorine, oxygen and Cu 1S(1/2) peaks up to compositions corresponding to the formation of YBa2Cu3O5.0F3 beyond which there is no further change.