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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
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Identification of Magic Numbers in Homonuclear Clusters: The ε3 Stability Ranking Function
Gabriel F S Fernandes1, Francisco B C Machado1, Luiz F A Ferrão1
1Departamento de Química , Instituto Tecnológico de Aeronáutica , São José dos Campos , SP 12228-900 , Brasil.
The Journal of Physical Chemistry. A
|December 19, 2019
Summary
A new stability ranking function (ε³) accurately identifies stable nanoclusters. This function uses kinetic and thermodynamic properties to predict magic numbers for various metal clusters, aligning with existing research.
Area of Science:
- Materials Science
- Computational Chemistry
- Condensed Matter Physics
Background:
- Cluster-assembled materials are gaining importance.
- A method to rank and identify stable clusters is needed.
- Existing methods may be complex or limited.
Purpose of the Study:
- To introduce and validate a simple stability ranking function (ε³) for nanoclusters.
- To assess the function's applicability across different elements (simple metals, main group, transition metals).
- To compare the function's predictions with experimental and theoretical data.
Main Methods:
- Application of the ε³ stability ranking function to nanoclusters of Na, Mg, Al, Ti, and Cu.
- Derivation of ε³ function parameters from molecular wave functions.
- Utilizing kinetic descriptors (ionization potential, electronic excitation energy) and thermodynamic descriptors (atomization free Gibbs energy).
Main Results:
- The ε³ function successfully ranked the stability of studied nanoclusters.
- The function identified relevant magic numbers for these clusters.
- Results showed good agreement with previous experimental and theoretical studies.
Conclusions:
- The ε³ function is a simple yet effective tool for predicting nanocluster stability.
- This function has broad applicability across the periodic table for various metal types.
- It offers a valuable index for materials science and engineering applications.
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