The Millimeter- and Submillimeter-Wave Spectroscopy of Low Temperature Collisions

俄亥俄州州立大学的Frank DeLucia和Eric Herbst教授由实验物理化学计划资助，进行低能分子碰撞的实验和理论研究。 目标是了解动力学，光谱学和相互作用，这些相互作用决定了氦，氢，甲醛和一氧化碳等小物种的低温（10K）碰撞行为。 在实验条件下，碰撞能小于碰撞伙伴之间的货车范德华络合物的结合能。 (The井深通常对应于小于几十度的温度）。 沿着提供这类碰撞的数据，PI将开发新的实验技术，如状态到状态的非弹性转动能量转移，碰撞冷却方法和新的分子离子生产方法。特别是，他们将尝试一种分子束脉泽方案，这将使他们能够克服一些以前遇到的热平均问题。 将进行一些从头计算，这将有助于数据解释。 这项工作的成功成果将是描述超冷分子之间相互作用的高度精确的势，这些势将作为量子理论的基准。这些基础研究涉及量子化学和散射理论的相互关联的领域，以及我们对星际介质中化学过程和能量转移的理解。 这项工作还将提供用于解释天体物理和大气物种观测的光谱数据。

Professors Frank DeLucia and Eric Herbst of the University of Ohio State University are funded by the Experimental Physical Chemistry program to perform experimental and theoretical studies of low energy molecular collisions. The goal is to understand the dynamics, spectroscopy and interactions which govern the behavior of low temperature (10K) collisions of small species such as helium, hydrogen, formaldehyde and carbon monoxide. Under the experimental conditions here, the collision energies are less than the binding energies of the van der Waals complex between the collision partners. (The well depths typically correspond to temperatures of less than a few tens of degrees). Along with providing data on collisions of this type, the PIs will develop new experimental techniques such as state-to-state inelastic rotational energy transfer, collisional cooling methods and new molecular ion production methods. In particular, they will attempt a molecular beam maser scheme which should allow them to overcome some previously encountered thermal averaging problems. Some ab initio calculations will be performed that will aid in the data interpretation. A successful outcome of this work will be highly accurate potentials describing interactions between ultracold molecules that will serve as benchmarks for quantum theory. These fundamental studies relate to the interconnected areas of quantum chemistry and scattering theory, and our understanding of chemical processes and energy transfer in the interstellar medium. The work will also provide spectroscopic data of use for interpreting observations of astrophysical and atmospheric species.