Charging, Relaxation, and Polarization of Free Metal Nanoclusters

本研究项目的重点是研究大小从10到10,000个原子的碱性纳米团簇的电子、热和表面性质。这些实验将在束中的自由星团上进行，由蒸汽膨胀源产生，并由质谱仪检测。通过这种方式，纳米团簇可以作为精确已知大小的函数来研究，并且不会因为衬底效应而引起扭曲。该项目旨在了解：(1)被团簇极化势吸引和俘获的慢电子的命运；(2)团簇电偶极子极化率与温度的关系；以及(3)团簇与表面碰撞中高效电荷转移的起源。所有这些现象都与移动团簇电子的动力学有关。它们涉及有限多体系统和表面的基本物理，如纳米系统中的载流子散射和电子-振动耦合，结构和电子性质之间的相互作用，热膨胀和熔化转变。

The focus of this research project is on the electronic, thermal, and surface properties of alkali nanoclusters ranging in size from 10 to 10,000 atoms. The experiments will be carried out on free clusters in beams, generated in vapor expansion sources, and detected by mass spectrometers. In this way, nanoclusters can be studied as a function of precisely known size and without distortions caused by substrate effects. The project aims to understand: (1) the fate of slow electrons attracted and captured by the cluster polarization potential; (2) the temperature dependence of the electric dipole polarizability of clusters; and (3) the origin of highly efficient charge transfer in collisions of clusters with surfaces. All these phenomena are related to the dynamics of mobile cluster electrons. They touch upon the fundamental physics of finite many-body systems and surfaces, such as carrier scattering and electron-vibrational coupling in nanoscale systems, the interplay between structural and electronic properties, thermal expansion, and the melting transition.