Chemical kinetics and dynamics of M+(organic) molecules using single photon initiated dissociative rearrangement reactions (SPIDRR) measurements.


Gas-phase studies are important to many areas of science and technology. The ability to prepare molecular species in an environment devoid of complexities present in the condensed phase allows for high resolution measurement of molecular level details. This is particularly important when studying ion-molecule reactions where transition metals are involved. The open-shell, radical nature of the transition metal in combination with its charge promotes a host of low-energy chemical transformations with multiple reactive pathways open within a few eV of the zero point level of the encounter complex ground state. Moreover, barriers along these pathways are often submerged with respect to the separated reactant limit making both temporal and energetically resolved kinetic measurement challenging. However, it is precisely these qualities of a transition metal cation (a chemically reactive center that mediates low energy chemical transformations) that make it a desired catalytic active site and thus demands high resolution study. To this end, the single photon initiated dissociative rearrangement reaction (SPIDRR) technique was developed. This dissertation details the use of this novel tool toward measurement of the kinetics and dynamics of the Ni+ and Co+ mediated decomposition of several organic molecules. Ab initio quantum chemical calculations were performed to compliment these experimental studies. The potential energy surface has been determined at the DFT level to suggest the mechanistic features that occur during the metal mediated decomposition of an organic molecule. The combination of experiment and theory has permitted a far deeper understanding of the reaction dynamics and has proven integral towards explaining experimental observation. For example, emerging concepts that guide hydrogen transfers on Ni+ centered catalytic reactions have evolved from this synergistic combination.



Gas-phase. Kinetics. Dynamics. SPIDDR.