Ab-initio study of electronic and vibrational states of metal microclusters

由于金属微团簇具有较大的表面积比例，因此它们有望具有包括磁性在内的特殊性质。最近，实验研究已经成功地控制了这些星团的大小。本研究旨在详细分析金属微团簇及其聚集体的电子态和振动态。我们研究的第一个例子是表面带有五方元素的笼状结构的Ti8C；12&gt；金属微团簇的生长过程。与已知的富勒烯相比，我们应用紧束缚方案发现，在这种情况下没有形成大的笼子，更大的团簇是Ti8C；lt；12&gt；金属微团簇单元的组合。下一个例子是Rh微团簇，它有磁矩，尽管大块的Rh是非磁性的。本文的DVM计算再现了10个原子杂散的10MU B的实验结果。镶嵌在镍中的Rh杂波也被研究以获得比裸露情况下更高的磁矩。

Since metallic microclusters have large surface proportion compared to bulk, they are expected to have specific properties icluding magnetic properties. Recently, experimetal studies have progressed to be sucessful to control the sizes of these clusters. The present study aims to analyze in detail the electronic and vibrational states of the metallic microclusters and their aggregates.The first example we have studies was the growth process of the Ti_8C_<12> metallic microcluster, which has a cage like structure with pentagonal elements on the surface. Compared with the well-known fullerenes, we applied tight-binging scheme to find out that no large cages formed for this case and the larger clusters are the combimations of the unit of Ti_8C_<12> metallic microclusters.The next example is the Rh microcluters, which has magnetic moments, although the bulk Rh is nonmagnetic. The present DVM calculation reprodeced the experimental findings of 10 mu B at 10 atom cluter. Embedded cluters of Rh in Ni have also studied to give higher magnetic moments compared to the bare cases.