The Assembly and Spectroscopic Interrogation of Hydrogen Clusters in Helium Droplets

在这个由化学部实验物理化学计划资助的项目中，Vilesov将研究被困在超冷氦液滴中的氢分子和团簇的基本性质。这项工作包括两个部分。在第一个，重点是H2，D2，和HD分子簇成具有不同性质的发色团。第二部分将致力于研究纯氢团簇，特别注意那些在30个分子以下的大小范围。红外和汽车光谱将用于这些研究。对超冷液氦液滴中捕获的分子和团簇的研究提供了常规技术无法获得的有关其行为的新信息。被捕获的物质不仅振动，而且它们还在液滴中旋转，这表明被捕获的物质和包埋浴之间的相互作用是最小的。相对于那些属于气体分子的旋转能量的微小变化允许定量评估将分子结合到液滴中的力。

In this project funded by the Experimental Physical Chemistry Program of the Chemistry Division, Vilesov will investigate fundamental properties of hydrogen molecules and clusters trapped in ultracold helium droplets. The work consists of two parts. In the first, the focus is on H2, D2, and HD molecules clustered to chromophores with different properties. The second part will be devoted to the study of neat hydrogen clusters, special attention being given to those in the size range below 30 molecules. Infrared and CARS spectroscopy will be employed in these investigations.Research on molecules and clusters entrapped in ultracold droplets of liquid helium provides new information on their behavior not available with conventional techniques. Not only do the trapped species vibrate, but they also rotate in the droplets, which indicates that the interaction between the trapped species and the embedding bath is minimal. The slight changes in the rotational energies relative of those that pertain to gaseous molecules allow a quantitative assessment of the forces that bind the molecules into the droplets.