Beam deflection and photoabsorption studies of metal, water, and 'superatom' nanoclusters

纳米团簇束（由几个到几千个原子或分子组成的小尺寸聚集体）的研究利用原子和分子束的概念和方法来深入了解纳米尺度以及体尺度和表面现象的微观机制。该项目将利用具有强永久或感应电偶极矩的金属和水团簇系统的激光诱导碎裂和电场诱导偏差。主要目标是研究水、金属和“超原子”团簇的电敏感性与它们内部温度的关系。“超原子”是特别稳定和对称的团簇，被认为具有封闭的电子和几何壳层。研究结果将揭示纳米级冰柱的熔化转变、金、银团簇和表面杂质之间的电荷转移、“超原子分子”的形成以及随着粒子尺寸一个原子一个原子地增大，电子和结构基序之间的相互作用等效应。这些实验将为许多当前的理论模型提供严格的测试和基准。在技术方面，该项目更广泛的影响在于它与理解纳米材料构建模块以及分子传感器和纳米催化剂的优化相关。在人文方面，该项目将为研究生提供跨学科领域的全面培训，促进本科生参与研究，并为跨部门招聘和推广活动做出贡献。

Studies of beams of nanoclusters (small-sized aggregates made up of several to several thousand atoms or molecules) utilize atomic and molecular beam concepts and methods to gain insight into the microscopic mechanisms of nano-scale as well as bulk-scale and surface phenomena. This project will utilize laser-induced fragmentation and electric field-induced deviation of metal and water cluster systems possessing strong permanent or induced electric dipole moments. The main goal is to investigate the electric susceptibility of water, metal, and "superatom" clusters as a function of their internal temperature. "Superatoms" are particularly stable and symmetric clusters which have been proposed to possess closed electronic and geometrical shells. The results will reveal such effects as the melting transition of a nanoscale icicle, charge transfer between gold and silver clusters and surface impurities, the formation of "superatomic molecules," and the interplay between electronic and structural motifs as the particle size increases atom-by-atom. The experiments will provide stringent tests and benchmarks for a number of current theoretical models. On the technical side, the broader impact of the project lies in its relevance for understanding nanomaterial building blocks and for optimization of molecular sensors and nanocatalysts. On the human side, the program will offer graduate students thorough training in an inherently interdisciplinary field, promote undergraduate involvement in research, and contribute to interdepartmental recruitment and outreach activities.