Time-resolved electron energy loss spectroscopy of surface kinetics

Abstract

The study of adsorbate kinetics on single crystal surfaces by time-resolved electron energy loss spectroscopy with resolution as fast as a few milliseconds is described. Rapid temperature and pressure jumps are used to perturb the system out of equilibrium, and the subsequent relaxation is followed in real time by a parallel data acquisition scheme achieved by incorporating a multichannel detector into the electron energy analyzer. Chemical transformations and structural transitions on surfaces are probed directly by recording as a function of time vibrational spectra of absorbed molecules. Surface kinetics problems that can be uniquely studied by this technique are identified. In addition, the potentials as well as the limitations set by the present capabilities of the instrument are also addressed.