Ferromagnetic clusters on surfaces: correlation of structural, electronic and magnetic properties probed by STM and SP-STS

该项目属于优先项目1153，重点是确定使用STM实现的最高横向分辨率表面上单个簇的结构和电子特性。它们是由一个源产生射流的大小选择的纳米颗粒沉积在超高真空中制备的。原子尺度下的极高横向分辨率允许对单个星团进行表征，而不仅仅是像横向平均方法那样对整体进行表征。这将能够高精度地确定与尺寸相关的属性。制备一个“完美”尺寸的选定簇束可以根据晶格常数的知识来确定体积。但是，自由团簇的形状和表面体积比，这些决定电子和磁性行为的特性，通常是未知的。在金属团簇与金属表面的相互作用对形状、电子和磁性有重大影响的表面上的系统团簇，这种行为变得更加重要。因此，用一种允许确定单个团簇的结构、形状和电子行为的方法进行调查，将对理解团簇性质具有重要意义。

This project within the Priority Programm 1153 focusses on the determination of structure and electronic properties of individual clusters on surfaces realized by highest lateral resolution using an STM. They are prepared by a source generating a jet of size-selected nanoparticles which are deposited in ultra-high vacuum. The extremely high lateral resolution down to the atomic scale allows a characterization of individual clusters, not only of ensembles as with laterally averaging methods. This will enable the determination of size-dependent properties with high precision. The preparation of a "perfectly" size selected cluster beam allows the determination of the volume regarding the knowledge of the lattice constant. But, the shape and thus the surfaceto-volume ratio, properties which significantly determine electronic and magnetic behavior, are often already unknown for free clusters. This behavior becomes even more important for the system cluster on a surface where the interaction of the metallic cluster with the metallic surface have a significant influence on shape, electronic, and magnetic properties. The investigation with a method allowing the determination of structure, shape, and electronic behavior of single individual clusters will therefore be of great relevance for the understanding of cluster properties.