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In Situ SIMS and IR Spectroscopy of Well-defined Surfaces Prepared by Soft Landing of Mass-selected Ions
Published on: June 16, 2014
Size-dependent structural evolution and chemical reactivity of gold clusters
Bokwon Yoon1, Pekka Koskinen, Bernd Huber
1School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332-0430, USA.
Summary
Researchers studied gold cluster anions (Au(15) to Au(24)) using theory and experiments. They found a size-dependent reactivity pattern for oxygen adsorption, explained by electronic structure and a partial-jellium model.
Area of Science:
- Physical Chemistry
- Materials Science
- Computational Chemistry
Background:
- Gold clusters exhibit unique properties influenced by size and charge.
- Understanding the reactivity of small metal clusters is crucial for catalysis and materials design.
Purpose of the Study:
- To determine ground-state structures of gold cluster anions (Au15- to Au24-).
- To investigate the adsorption of molecular oxygen (O2) on these clusters.
- To elucidate the electronic factors governing their chemical reactivity.
Main Methods:
- Joint application of first-principles density functional theory (DFT) calculations.
- Experimental validation using photoelectron spectroscopy.
- Analysis of electronic structure and bonding characteristics.
Main Results:
- Optimal ground-state structures for Au(15) to Au(24) anions were identified.
- A clear size-dependent pattern in O2 adsorption reactivity was observed.
- Reactivity correlates with electronic shell structure and d-band electron localization.
Conclusions:
- The chemical reactivity of gold cluster anions is governed by their electronic shell structure, described by a partial-jellium model.
- Geometric structure is influenced by localized d-band electrons, impacting reactivity.
- Computational and experimental methods provide a unified understanding of cluster behavior.
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