Spectroscopy of Diatomic Molecules at Long Range

实验物理化学和原子、分子和光学物理项目支持康涅狄格大学物理系的威廉·C·斯特瓦利继续进行远距离双原子分子的光谱研究。在这项工作中，斯特瓦利教授将与菲利普·L·古尔德教授合作，后者是研究超冷原子碰撞的专家。他们将使用全光学多重共振光谱来研究超冷碱原子的高分辨率光缔合光谱。重点将放在碱金属双原子(如钾或铯二聚体)的高激发态上，但斯特瓦利和古尔德也将尝试观察Cs-H2等原子-分子的光缔合。长距离的分子是原子之间相隔很远的分子，但引力仍然足够强，足以保持分子的性质。这类分子目前引起了极大的兴趣，部分原因是出现了新的效应，这将扩大我们对分子势能曲线的了解，部分原因是它们与激光冷却和囚禁以及玻色-爱因斯坦凝聚的工作有关。在这一新的合作努力中进行的研究将极大地增加我们对化学键的理解，因为它揭示了吸引和凝聚原子的微妙作用力，原子之间的距离很大。这些研究的成功完成将提供有关原子间作用力的非常详细的信息，这些信息反过来对我们理解原子碰撞和原子组装成从分子到团簇再到凝聚相的更高聚集态是至关重要的。

The Experimental Physical Chemistry and the Atomic, Molecular and Optical Physics Programs support William C. Stwalley of the Physics Department at the University of Connecticut in his continuing spectroscopic studies of diatomic molecules at long range. In this effort, Prof. Stwalley will collaborate with Prof. Phillip L. Gould, an expert in collisions of ultracold atoms. They will investigate the high-resolution photoassociative spectroscopy of ultracold alkali atoms using all optical multiple resonance spectroscopies. Emphasis will be on highly excited states of alkali metal diatomics (e.g., potassium or cesium dimers), but Stwalley and Gould will also attempt to observe photoassociation of atom-molecules such as Cs-H2. Molecules at long range are molecules in which the atoms are separated by very large distances, yet attractive forces are still strong enough to maintain a `molecular` nature. Such molecules are of great current interest, partly because new effects show up which will extend our knowledge of molecular potential curves, partly because of their relevance to the work in laser cooling and trapping and Bose-Einstein condensation. The studies that will be carried out in this new collaborative effort will greatly increase our understanding of chemical bonding by revealing the subtle forces that act to attract and `congeal` atoms separated by large internuclear distances. Successful completion of these studies will furnish highly detailed information on interatomic forces which, in turn, are of fundamental importance to our understanding of atomic collisions and the assembly of atoms into higher states of aggregation ranging from molecules, to clusters, and on to condensed phases.