Cluster Assembled Materials
It is now some 15 years since atomic clusters were first produced and investigated in laboratories. Since then, knowledge concerning clusters has enjoyed rapid and sustained growth, and cluster research has become a new branch of science.
The most prominent example is carbon, which exists not only in two crystalline forms, graphite and diamond, but also in a cluster-assembled structure, fullerite, where C60 units are arranged in a face-centered cubic lattice under normal conditions. Other carbon cluster units, such as C70, C84, C96 have also been assembled to form solids.
There is currently great interest in the prospect of producing new materials made up of small atomic clusters. Such cluster-assembled materials can differ significantly from their crystalline counterparts. Mechanical, electronic, optical and other properties are expected to be different for such assemblies, and this should make them good potential candidates as new building materials for electronic devices. Also, the quantum effects which occur in materials of small size and low dimension, impart special properties to these materials.