In this project in the Physical Chemistry Program of the Chemistry Division, Bruce Hudson will study the UV resonance Raman spectra of a broad range of conjugated and non-conjugated polyenes and selected triatomics. Information about vibrational and electronic ground and excited states to be gathered will be related to the mechanism of nuclear/electron coupling in molecules in processes such as photodissociation, photoisomerization, and unimolecular reaction. Experimental methods involving the determination of absolute Raman intensities, depolarization ratio dispersion, tunable excitation, and photochemical generation of subject species in vapor and with matrix isolation will be developed. A new UV spectrograph will be constructed and a Ti:sapphire laser will be developed to produce tunable far-uv radiation. %%% Professor Hudson's research group has developed unique spectroscopic capabilities that allow the study of the initial motion of a molecule which has been excited by a vacuum- ultraviolet photon from its ground electronic energy state. Experiments using these techniques can make important contributions to the understanding of energy flow and intramolecular dynamics in the highly excited states of polyatomic molecules.