Soft-x-ray-emission study of the influence of Li+-doping, irradiation, andplastic deformation on CuO

The influence of Li+ doping, shear under pressure, and irradiation with He or electrons on the oxygen 2p-band and valence states of copper ions in Cu O was studied using soft-x-ray emission spectroscopy. In the case of irradi ation and shear under pressure the transformation of the spectrum shape is explained by the appearance of Cu2O. The doping with lithium leads to the a ppearance of copper ions with formal valency of 3+. It was also established that the presence of lithium ions prevents Cu2O phase forming without a de pendence on the plastic deformation value. The reasons and possible mechani sms of the CuO --> Cu2O transitions in the oxides studied are discussed. [S 0163-1829(99)01402-2].