Small Cluster Chemistry
Our activities encompass studies of a broad variety of physicochemical
properties of cluster systems. The immense interest in clusters is fueled by the
recognition of the central role they play in many modern technologies and in
natural phenomena. The potential of clusters as a means of optimization of
existing technologies, developing principally new technological processes,
materials, and devices, and in managing natural phenomena, especially those of
environmental concern, is truly unparalleled. To make this potential a reality a
comprehensive understanding of the properties of clusters as a function of their
material(s), size, structure, temperature, etc. is needed.
The emphasis in our program is on fundamental studies leading to such an
understanding. Its particular strength is that it combines both experimental and
theoretical components, which synergistically enhance each other.
Our research focuses on metal clusters because of their particular technological
relevance. The elements studied vary from alkali, through transition, to coinage
metals and their combinations. The properties investigated include geometrical
structures, stability, phases and phase changes, fragmentation mechanisms,
electronic features (e.g., ionization potentials, electron affinities), chemical
reactivity with a broad variety of molecules, optical and magnetic properties,
etc. The cluster features change, in general, with size, and the different
properties may be correlated. The central goals include uncovering and
understanding the size-dependence of and the correlations between the different
features. For example, the chemical reactivity of a cluster of a given metal
with a chosen reactant molecule may strongly depend on the cluster size,
structure, and temperature. Unraveling the mechanisms through which these latter
affect the reaction pathways and rates is crucial for improving, or even fully
optimizing, the efficiency and selectivity of real catalysts. |