Assembly and spectroscopic interrogation of large atomic and molecular clusters in helium droplets

通过这个由化学学部化学结构、动力学和机制项目资助的奖项，来自南加州大学的Andrey Vilesov教授和他的研究生研究人员将在氦超流体液滴中实现的超低温下研究原子和分子的组装成簇。这些研究将集中在金属原子和碳氢化合物分子等物种上。实验将在液滴本身进行，采用激光方法结合质谱。许多组装的簇也将通过电子显微镜成像。待研究的团簇的大小从几个原子/分子到数千万个原子/分子不等，组成从单一物种团簇到混合的核-壳金属分子团簇。这些研究的目的是探讨低温聚集的机制，并阐明低温聚集的结构和激发。Vilesov教授建议使用的大氦滴可能是制造新的有趣材料的有用载体。在氦液滴中组装和研究纳米尺寸的团簇不仅将扩展目前研究人员可用的纳米材料的种类，而且将有助于建立新的低温制造物理方法。与Vilesov教授一起工作的学生已经并将继续接受这些尖端技术的广泛培训，包括但不限于快速电子技术，高真空方法，激光方法和高分辨率显微镜。Vilesov教授在国际合作方面有着悠久的历史，这很可能会通过这项工作继续下去。

Through this award, funded by the Chemical Structure, Dynamics, and Mechanisms Program of the Division of Chemistry, Prof. Andrey Vilesov from the University of Southern California, along with his graduate student researchers, will study the assembly of atoms and molecules into clusters at the ultralow temperatures achievable in superfluid droplets of helium. These studies will focus on such species as metal atoms and hydrocarbon molecules, among others. The experiments will be carried out in the droplets themselves by employing laser methods in conjunction with mass spectroscopy. Many of the assembled clusters will also be imaged by way of electron microscopy. The clusters to be studied will range in size from just a few atoms/molecules to tens of millions and vary in composition from single-species clusters to mixed, core-shell metal-molecule clusters. The goal of these studies is to investigate the mechanisms of low temperature aggregation and to elucidate the structure and excitations in such clusters with size. The large helium droplets that Prof. Vilesov proposes to use may be useful vehicles for making new and interesting materials. The assembly and study of nanometer-sized clusters in droplets of helium will not only extend the variety of the nanomaterials available to researchers today but will also contribute toward the establishment of novel physical methods of low temperature fabrication. Students working with Prof. Vilesov have and will continue to receive extensive training in such cutting-edge technologies including, but not limited to, fast electronics, high vacuum methods, laser methods, and high resolution microscopy. Prof. Vilesov has a strong history of international collaboration and this will likely continue through this work.