Electronically stimulated desorption

In the valence region, desorption of neutrals predominates; nevertheless most research has been on ions up to recently. New methods have made the investigation of neutrals easier, and angle as well as energy distributions have been reported; on this basis the salient mechanisms can be deduced both for chemisorbed and physisorbed layers. Desorption of ions and, in particular, of fragment ions, is strongly enhanced following higher excitations. These can most easily be reached via Auger decay of adsorbate core holes. Considerable detail of understanding is obtainable through polarization-dependent measurements with synchrotron radiation. The importance of many-body interactions at surfaces (increased localization by hole-hole interaction; increased delocalization by screening) becomes obvious. The field of stimulated desorption has profitted strongly from the improved understanding derived from the mature state of surface spectroscopies.