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William C. Stwalley继续进行双原子分子的长程光谱研究。在这项工作中，Stwalley教授将与超冷原子碰撞专家Phillip L. Gould教授合作。他们将利用全光学多重共振光谱研究超冷碱原子的高分辨率光结合光谱。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Stwalley和Gould也将尝试观察原子-分子（如Cs-H2）的光关联。远距离分子是指原子之间相隔很远的分子，但其引力仍然强大到足以维持其“分子”性质。这类分子目前引起了极大的兴趣，部分原因是新效应的出现将扩展我们对分子势曲线的认识，部分原因是它们与激光冷却和俘获以及玻色-爱因斯坦凝聚的工作有关。在这项新的合作努力中进行的研究将通过揭示吸引和“凝结”相隔较大核间距离的原子的微妙力量，大大增加我们对化学键的理解。这些研究的成功完成将提供关于原子间作用力的非常详细的信息，反过来，这对我们理解原子碰撞和原子组装到更高的聚集状态（从分子到簇，再到凝聚相）具有根本的重要性。

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.