The diffusion of molecular species on solid surfaces is an important step in most heterogeneous reaction mechanisms. The detailed investigation of surface diffusion is the subject of this research project supported by the Analytical and Surface Chemistry Program. A pulsed molecular beam-surface infrared spectrometer system has been constructed to investigate the transport of CO, NO, and substituted isonitriles on stepped palladium and nickel surfaces. Step and terrace populations will be characterized, low and high coverage diffusion measurements made, and transient mobility studies carried out during the course of this project. This work will provide a very comprehensive picture of molecular transport on well characterized surfaces. %%% The transport of molecules across surfaces is an important step in reactions which are mediated by these surfaces. In order to develop a detailed understanding of surface reactions such as corrosion and catalysis, information about the mechanism and rate of surface diffusion must be obtained. This research project combines molecular beam dosing methods with surface infrared spectroscopy to directly measure the diffusion of small molecules on catalytically important surfaces.
