The effect of 20 to 120keV electron irradiation upon the properties of thin-film samples was studied. The displacement energy for O in CuO2 planes was found to be equal to 8.4eV for irradiation along the c-axis. The creation kinetics of in-plane O vacancies were studied, and were found to be governed by the athermal recombination of vacancy-interstitial pairs. The associated recombination volume comprised some 21 unit cells. The upper limit on the displacement energy for chain O atoms was estimated to be 2.8eV.

S.K.Tolpygo, J.Y.Lin, M.Gurvitch, S.Y.Hou, J.M.Phillips: Physical Review B, 1996, 53[18], 12462-74