Spectroscopic Investigations of Organic Molecules on Graphite Surfaces

摘要

The research program conducted over the past three years under ARO sponsorship focused on the spectroscopic investigation of polycyclic aromatic molecules adsorbed onto the surface of graphite. The overall aim of the investigation was to characterize the structural features of the adsorbed complex and to identify the nature of the interactions which stabilize them. Our approach was to examine a series of prototypical aromatic molecules bound to highly oriented pyrolytic graphite by optical, magnetic resonance, and raman spectroscopy. Results in several areas of significance were obtained in the course of the research program. In summary, these were: observance of optical and ODMR spectra of photoexcited quinoline and quinoxaline on graphite; observance of resonance raman scattering from chlorophyll on graphite; observance of ODMR from chlorophyll on graphite; determination of the chlorophyll geometry on the graphite surface; demonstration of the feasibility of raman-detected ODMR on surfaces.