This award from the Chemistry Research Instrumentation Program will help the Department of Chemistry at Columbia University acquire an AC-80 NMR spectrometer that will operate as a multiuser steady state (SS) and time resolved (TR) instrument for the detection of chemically induced dynamic nuclear polarization (CIDNP). The Principal Investigators will employ the instrument to investigate, by multinuclear (1H, 13C, 31P) SS-CIDNP and TR-CIDNP, the mechanisms of diverse photochemical systems including (1) the reactions of organic radical ions produced by photosensitized electron transfer; (2) the photochemistry of phosphites and phosphine oxides; (3) the measurement of exit rates of radicals, produced by photolysis of ketone from micelles as a function of micelle size and radical structure; (4) the photosensitized cleavage of thymine dimers in systems that model photoinduced repair of damaged DNA; (5) a search for CIDNP in oriented biological macromolecular solids; and (6) time resolved CIDNP of biradicals produced by photolysis of cyclic ketones. In addition to the research described above, the instrumentation will be used by undergraduates in advanced organic chemistry laboratories, in physical-analytical laboratories, in research project laboratories, in senior research and in summer undergraduate research. The instrument will be coupled into an "electronic smart classroom" containing state-of-the-art multimedia facilities to allow students and faculty to introduce data directly from experiments into lecture, recitation and discussion groups on demand. Finally, the computer interface will be employed to produce modules that will simulate important NMR experiments and will be accessible to students on their own personal computers through ColumbiaNet. Nuclear Magnetic Resonance (NMR) spectroscopy is the most powerful tool available to the chemist for the elucidation of the structure of molecules. It is used to identify unknown substances, characterize specific arra ngements of atoms within molecules, and to study the dynamics of interactions between molecules in solution. Access to state-of-the-art NMR spectrometry is essential to chemists who are carrying out frontier research. The results from these NMR studies are useful in areas such as polymers and catalysis, and in biology.
