Book of Abstracts Book of Abstracts - Universität Konstanz

Passivation, charging and optical properties of gold nanoclusters
Hannu Häkkinen
Department of Physics, Nanoscience Center, University of Jyväskylä, Finland
B - 42
Nanoclusters and nanoparticles are currently a subject of intense experimental and
theoretical research efforts due to their unique physical and chemical properties that might be of
potential use in future nanotechnologies. The properties of Gold nanoclusters are extraordinary
sensitive to a number of factors, including size, charge state, passivation by inorganic ligands,
and the type and amount of impurity atoms. Varying these factors allows one to "tune" or
"functionalize" the electrical, optical and chemical properties in a desired way. This contribution
will discuss phosphine- and thiol-passivated WAu12, Au39 and Au55 clusters in light of recent
large-scale density functional simulations. It is shown that the properties of the gold core can
easily be controlled by changing the ligand from π-acidic to σ-donating, i.e., by “chemical
charging”. Exchange of phosphine ligands to CO molecules is energetically possible for some
of the clusters, making them interesting candidates for nanocatalysts for CO oxidation.
Figure 1. Spacefill visualization of trimethylphosphine-passivated Au 55 chloride Au 55(PMe 3) 12Cl 6 – a model for the
famous “Schmid cluster” (ref. 1).
References
[1] G. Schmid, Chem. Rev. 92, 1709 (1992).
87