Published online by Cambridge University Press: 28 February 2011
The electronic structure and properties of small clusters are strongly dependent on their size. These size specific properties are illustrated by confining the discussion to three different topics (1) interaction of hydrogen with clusters (2) effect of temperature and magnetic field on the magnetization of clusters and (3) reaction of clusters with gas atoms. It is shown that the electronic energy levels that are strongly dependent on cluster size give rise to the size specific electronic properties of clusters. In cluster hydrides certain elements are found to absorb more hydrogen per atom in cluster form than in a crystalline form. The magnetization of clusters increases as a function of cluster size and externally applied magnetic field. In clusters reacting with gas atoms, it is possible to find the product cluster in an electronically excited state. The energetics of these states are strongly dependent on the cluster size and the reacting gas.