Laser spectroscopy of transient molecules/IVR mediated torsion

这里提出的研究的一部分是关于不稳定分子的电和磁性质的表征。这些分子具有高度的活性，因此它们的寿命很短，只有一毫秒或更短。由于它们作为反应中间体，不稳定分子参与了物理学、化学、天体化学和其他科学分支中的各种过程。这些分子的相关性的例子是监测我们大气中的污染物，臭氧消耗的性质，监测半导体器件的制造，了解燃烧和其他烟尘形成过程，以及行星和恒星大气的演变。研究的另一部分是关于当能量快速沉积到分子的一个振动模式时会发生什么的问题。这是理解一个孤立分子如何将其能量重新分配到其多个自由度的关键问题。这在化学动力学和激光化学中具有重要意义，其中期望控制化学反应。为了找到这个问题的答案，我们需要更多地了解分子中不同的振动如何相互作用。事实证明，如果分子具有一个或多个容易激活的振动模式，那么它可以比没有这种模式的分子更容易地分配它从外部来源接收的能量。此类分子的实例是乙烷（CH 3CH 3）和CH 3SiH 3。乙烷中的两个甲基可以围绕C-C键以相反的方向旋转。与例如C-H模式相比，该模式需要相对少量的能量来激活。

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.