Uncovering Clar's aromatic -sextet rule in the Hubbard model using Maximum Probability Domain Partitions
Daria Tolstykh1, Laurent Lemmens1, Stijn De Baerdemacker2
1Ghent Quantum Chemistry Group, Department of Chemistry, Ghent University, Ghent, Belgium.
Journal of Computational Chemistry
|January 8, 2022
Summary
Clar's aromatic sextet rule for polycyclic benzenoid hydrocarbons is supported by fundamental electron distribution probabilities. Maximizing these probabilities reveals the dominance of Clar structures, offering new quantum chemical insights.
Area of Science:
- Quantum chemistry
- Theoretical chemistry
- Chemical physics
Background:
- Clar's aromatic sextet rule is a qualitative tool for analyzing polycyclic benzenoid hydrocarbons.
- Existing quantum chemical explanations for Clar's rule have limitations in their applicability.
Purpose of the Study:
- To investigate the theoretical underpinnings of Clar's aromatic sextet rule.
- To demonstrate how electron distribution probabilities support the rule in various quantum chemical regimes.
Main Methods:
- Analysis of electron distribution over domain partitions.
- Exploration within mean-field and static correlation frameworks.
- Identification of domain partitions that maximize fundamental probabilities.
Main Results:
- Fundamental probabilities associated with electron distribution support Clar's rule.
- Domain partitions maximizing these probabilities correlate with dominant Clar structures.
- The findings hold true in both mean-field and static correlation regimes.
Conclusions:
- The study provides a probabilistic foundation for Clar's aromatic sextet rule.
- Maximizing electron distribution probabilities offers a novel quantum chemical basis for the rule.
- Extending probability-maximization methods could yield new quantum chemical concepts.
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