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Updated: Jun 2, 2026
10:22
In Situ SIMS and IR Spectroscopy of Well-defined Surfaces Prepared by Soft Landing of Mass-selected Ions
Published on: June 16, 2014
Planar structures of medium-sized gold clusters become ground states upon ionization
Mohammad Ismaeil Safa1, Ehsan Rahmatizad Khajehpasha1, Jonas A Finkler1
1Department of Physics, University of Basel Klingelbergstrasse 82 CH-4056 Basel Switzerland stefan.goedecker@unibas.ch.
Nanoscale Advances
|June 1, 2026
Summary
Positively ionized gold clusters surprisingly favor planar structures over compact ones due to charge effects. Thermodynamic stability further enhances planar structure preference in gold atom clusters.
Area of Science:
- Physical Chemistry
- Materials Science
- Computational Chemistry
Background:
- Neutral gold clusters typically adopt compact structures for sizes above 22 atoms.
- Understanding cluster stability is crucial for applications in catalysis and nanotechnology.
- Ionization significantly alters the electronic and structural properties of atomic clusters.
Purpose of the Study:
- To investigate the structural stability of ionized gold clusters (22-100 atoms).
- To compare the energetic preference between compact, cage, and planar structures in ionized gold clusters.
- To analyze the influence of charge and temperature on cluster structural transitions.
Main Methods:
- Utilized the Minima Hopping algorithm for exploring potential energy surfaces.
- Employed a machine-learned potential adapted for ionized clusters via a charge-correction term.
- Incorporated Coulomb interactions and charge screening effects into the computational model.
Main Results:
- Positively ionized gold clusters show a structural transition towards planar configurations at higher charges.
- Planar structures become energetically more favorable than compact and cage structures.
- Finite-temperature stability analysis indicates further stabilization of planar gold cluster structures.
Conclusions:
- Charge plays a critical role in determining the preferred structure of gold clusters.
- Planar gold cluster structures exhibit enhanced stability under specific ionization and temperature conditions.
- The developed charge-correction method accurately models ionized cluster behavior.
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