Kinsey, James L.2009-06-042009-06-041995Stevens, Richard Eric. "Raman spectroscopy of photodissociating molecules." (1995) Diss., Rice University. <a href="https://hdl.handle.net/1911/16886">https://hdl.handle.net/1911/16886</a>.https://hdl.handle.net/1911/16886Dissociative Resonance Raman Spectroscopy has been used to probe the dissociation dynamics of two different molecules, dimethyl zinc and methyl mercaptan. A method for analytically describing potential energy surfaces by the use of rational approximants is described. A rigorous, systematic algorithm to remove spurious singularites from such approximants is presented. A tunable, narrow band UV laser system has been developed capable of generating 10 nsec pulses of 10 mJ energy, with a bandwidth of less than 1 $\rm cm\sp{-1}.$ The tuning range of the ArF final amplifier is 192 to 194 nm, and use of a stimulated Raman scattering cell allows for tuning up to 205 nm at 0.5 mJ energy per pulse. The Raman spectrum of DMZ is complicated by the appearance of Zn atom and ion lines. The fundamental and 1st overtone of a methyl umbrella mode are the only Raman features seen. The Raman spectrum of methyl mercaptan shows a progression which we assign to the C-S stretching mode. A strong feature we assign to the S-H stretching fundamental exhibited no overtones. Our results show that a previous assignment from a low resolution spectrum taken in another laboratory is erroneous. Methyl mercaptan's Raman spectrum is complicated by the appearance of CS fluorescence and atomic carbon fluorescence. A pathway is proposed for the multi-photon formation of these emitting species at 193 nm.122 p.application/pdfengCopyright is held by the author, unless otherwise indicated. Permission to reuse, publish, or reproduce the work beyond the bounds of fair use or other exemptions to copyright law must be obtained from the copyright holder.Physical chemistryThesisTHESIS CHEM. 1995 STEVENS