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Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Larger water clusters with edges and corners on their way to ice: structural trends elucidated with an improved
Bernhard Bandow1, Bernd Hartke
1Institut für Physikalische Chemie, Christian-Albrechts-Universität, Kiel, Germany.
The Journal of Physical Chemistry. A
|April 28, 2006
Summary
This study introduces an efficient parallel evolutionary algorithm for finding global minimum energy structures in molecular clusters. The new method accelerates calculations and refines predictions for water cluster structures, impacting understanding of phase transitions.
Area of Science:
- Computational Chemistry
- Materials Science
- Statistical Mechanics
Background:
- Determining global minimum energy structures for molecular clusters is computationally challenging.
- Previous evolutionary algorithms faced serial bottlenecks, limiting scalability.
- Accurate modeling of water clusters is crucial for understanding their properties.
Purpose of the Study:
- To develop a highly efficient parallel implementation of an evolutionary algorithm for global minimum structure searches.
- To overcome serial bottlenecks in traditional evolutionary algorithms.
- To apply the new algorithm to challenging problems like water clusters.
Main Methods:
- A novel parallel evolutionary algorithm was developed, replacing the generation concept with a pool concept.
- The algorithm was implemented to eliminate serial bottlenecks and enable efficient parallel processing.
- Tests were conducted on water clusters using the TTM2-F potential, modeling flexible, polarizable monomers.
Main Results:
- The new algorithm significantly reduced CPU time for finding global minima of water clusters.
- Improved structural proposals were generated, leading to qualitative changes in predictions of cluster transitions.
- Comparisons with ice structures suggest ice competitiveness for clusters above n=90.
Conclusions:
- The parallel evolutionary algorithm is highly efficient for global minimum structure searches in molecular clusters.
- The refined predictions offer new insights into water cluster structure transitions.
- The study provides a scalable computational approach for complex molecular systems.
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