Metal-cluster compounds: Model systems for nanosized metal particles

Abstract

Meta‐cluster compounds can be exploited advantageously to study the evolution, with increasing size of the molecules of the physical properties of metal clusters from molecular to bulk‐metal behavior. The metal‐cluster molecules are well‐defined, stoichiometric, chemical compounds. The molecules consist of a metal core of a variable number of atoms, surrounded by a shell of ligand atoms or molecules. Depending on the compound, the type of metal atom may be varied, whereas the core size can be changed from a few up to several thousands of atoms. Accordingly, these materials provide excellent model systems for monodisperse metal particles, embedded in a dielectric matrix, and can be investigated by the well‐known experimental techniques of solid‐state physics. © 1998 John Wiley & Sons, Ltd.

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