ELECTRONIC-ENERGY TRANSFER IN RARE-GAS SOLID ALLOYS STUDIED BY PHOTON-STIMULATED DESORPTION

Metastable-particle desorption from Ne-Ar and Ne-Kr solid alloys stimu lated by photon excitation were studied using synchrotron radiation as excitation source. Excitation of Ne excitons by optically allowed tra nsitions led mainly to desorption of the other components of the alloy revealing a very efficient energy transfer process. On the other hand , the excitation of the partially allowed electronic transition at the surface (2p(5) 3p) of Ne showed almost no electronic energy transfer to the matrix and desorption of Ne metastables was observed. A sharp e nhancement of the Ar metastable signal with respect to pure solid Ar w as also observed in the study of Ne-Ar alloys in the energy range belo w the excitation of Ne excitons. Different mechanisms for desorption a re suggested according to the energy region of excitation.