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Synthesis of Hierarchical ZnO/CdSSe Heterostructure Nanotrees
Published on: November 29, 2016
First-principles study of ring to cage structural crossover in small ZnO clusters
I Abdolhosseini Sarsari1, S Javad Hashemifar, Hadi Salamati
1Department of Physics, Isfahan University of Technology, Isfahan, Iran.
Journal of Physics. Condensed Matter : an Institute of Physics Journal
|November 23, 2012
Summary
The study reveals a structural shift in zinc oxide (ZnO) clusters from ring to cage forms around n=10. This transition influences their electronic properties and suggests a unique metastable structure for large ZnO nanostructures.
Area of Science:
- Computational materials science
- Solid-state chemistry
- Nanotechnology
Background:
- Understanding the structural evolution of small clusters is crucial for predicting properties of larger nanostructures.
- Zinc oxide (ZnO) clusters exhibit diverse structural motifs, including rings and cages, influencing their stability and electronic behavior.
Purpose of the Study:
- To investigate the origin and consequences of the ring-to-cage structural crossover in (ZnO)(n) clusters (n=2-16).
- To identify magic numbers and analyze the electronic structure changes associated with the structural transition.
- To explore potential metastable structures in large ZnO nanostructures.
Main Methods:
- Density functional theory (DFT) with full-potential calculations.
- Analysis of Zn-O-Zn bond angles, bond strengths, and coordination numbers.
- Application of many-body GW corrections to electronic structure.
- Extrapolation of cluster binding energies.
Main Results:
- A ring-to-cage structural crossover occurs around n=10 for (ZnO)(n) clusters.
- The (ZnO)(12) cluster is identified as the lowest magic number in the ground state.
- Finite temperature effects stabilize (ZnO)(9) as a magic cluster above 170 K.
- A size-induced redshift in electronic structure is observed, linked to the structural crossover.
- Evidence suggests a metastable structure for large ZnO nanostructures, distinct from the bulk.
Conclusions:
- The ring-to-cage transition in ZnO clusters is driven by changes in bonding and geometry.
- Magic numbers and temperature effects play significant roles in cluster stability.
- The observed electronic structure changes and potential metastable phase have implications for ZnO-based nanomaterials.
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