Novel Theories for the Dynamics of Chemical Reactions and Molecular Collisions

Understanding the dynamics and kinetics of chemical reactions is a subject of fundamental importance, receiving about 10% of Nobel chemistry prizes to date. Recent reviews of UK research in chemistry have identified theoretical and computational research on chemical reaction dynamics as one of the areas of UK chemistry that is world class. A wealth of important numerical data is currently being produced by computational methods for the dynamics of chemical reactions as the energy changes, or as time evolves, In addition, state-of-the-art experiments can now measure state-to-state angular distributions over an extended energy range. Understanding these scattering results is a very important, yet difficult, task. Moreover progress to date has been slow, because existing approximations often do not apply; rather new ideas and mathematical approximations are needed. The proposed research will develop new semiclassical approximations based, in part, on techniques from singularity theory. The approximations will possess the correct mathematical and physical concepts to describe and explain the striking effects often observed in the angular scattering, for example glories. In addition, a powerful mathematical procedure called preconditioned Pade reconstruction will be used to continue the scattering matrix into the complex angular momentum plane. New theories will also be developed for the complementary technique of nearside-farside scattering. These are simpler yet powerful theories that are increasingly be used in the scientific literature, and which provide novel physical insights into complicated structures in the angular scattering. They complement the more difficult semiclassical theories. Applications will be made to chemical reactions of current experimental and theoretical importance. For example, atmospheric reactions that consume Chlorine atoms, such as Cl + CH4 -> HCl + CH3, and oxygen reactions used to simulate space environmental effects, eg O + D2 -> OD + D, as well as fundamental state-to-state reactions whose properties are measured in molecular beams and laser experiments. The Project Partners are leading internationally-recognized researchers, namely GC Schatz (Northwestern University, USA), G Nyman (Goteborg University, Sweden), SC Althorpe (Cambridge University, UK) and D Sokolovski (Queen's University, Belfast, UK), whose total contribution to the research is worth 124,920.