Time dependent characteristics of electron tunnelling processes in H-, O- and F- formation on Ag(111)

Results of a study of electron transfer processes in the interaction of hyd rogen, oxygen and fluorine with Ag(1 1 1) are reported for a wide range of interaction times. We observe that for long interaction times, the yield of H-, resulting from resonant electron exchange, is much larger than what wo uld be expected for a jellium like metal surface with a similar work functi on. For short interaction times on the other hand, the yields follow the tr end for jellium like surfaces. These results confirm the predictions of the theoretical work using a wave packet propagation method (Phys. Rev. Lett. 80 (1998) 1996) on electron transfer on surfaces with L band gap. In the ca se of O- and F- significant effects were not observed. (C) 2000 Published b y Elsevier Science B.V. All rights reserved.