Autoionization Mediated by Electron Transfer

Electron-electron coincidence spectra of Ar-Kr clusters after photoionization have been measured. An electron with the kinetic energy range from 0 to approximately 1 eVis found in coincidence with the Ar 3s cluster photoelectron. The low kinetic energy electron can be attributed to an Ar þ Krþ þ Krþ final state which forms after electron transfer mediated decay. This autoionization mechanism results from a concerted transition involving three different atoms in a van der Waals cluster; it was predicted theoretically, but hitherto not observed