Laser spectroscopy of transient molecules/IVR mediated torsion

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One part of the research proposed here is concerned with the characterization of the electric and magnetic properties of unstable molecules. These molecules are highly reactive and thus live for a very short time, a millisecond or less. Because they act as reaction intermediates, unstable molecules take part in a wide variety of processes in physics, chemistry, astrochemistry, and other branches of science. Examples of the relevance of these molecules are the monitoring of pollutant in our atmosphere, the nature of ozone depletion, monitoring of the manufacturing of semiconductor devices, understanding combustion and other soot forming processes, and the evolution of the atmospheres of planets and stars. The other part of the research is concerned with the question of what happens when energy is rapidly deposited into one of the vibrational modes of a molecule. This is a key question to understanding how an isolated molecule redistributes its energy into its many degrees of freedom. This has important implications in chemical dynamics and laser chemistry where it is desirable to control chemical reactions. To find answers to this problem, we need to learn more about how different vibrations in a molecule interact. It turns out that if the molecule possesses one or more vibrational modes that are easily activated it can distribute the energy it receives from the outside sources much more easily than a molecule with no such modes. Examples of such molecules are ethane (CH3CH3) and CH3SiH3. The two methyl groups in ethane can rotate in opposite directions about the C-C bond. This mode requires a relatively small amount of energy to be activated as compared to for example the C-H mode.