Evaluation of Slight Changes in Aromaticity through Electronic and Density Functional Reactivity Theory-Based
Rodrigo Báez-Grez1, Ricardo Pino-Rios2
1Computational and Theoretical Chemistry Group, Departamento de Ciencias Químicas, Facultad de Ciencias Exactas, Universidad Andres Bello, República 275, Santiago 8370146, Chile.
ACS Omega
|July 5, 2022
Summary
This study evaluates aromaticity in fluorinated benzenes using delocalization and reactivity criteria. Results show delocalization indicators are sensitive to subtle aromaticity changes, complementing reactivity measures for a comprehensive understanding.
Area of Science:
- Computational chemistry
- Quantum chemistry
- Organic chemistry
Background:
- Aromaticity is crucial for understanding compound stability and reactivity.
- Electronic delocalization is a key stabilizing feature of aromatic compounds.
- Quantifying aromaticity requires diverse assessment methods.
Purpose of the Study:
- To systematically evaluate delocalization and reactivity criteria for assessing aromaticity in fluorinated benzenes.
- To compare these criteria with magnetic aromaticity measures like NICS(1).
- To explore the utility of various delocalization and reactivity indices.
Main Methods:
- Evaluation of delocalization indices: aromatic fluctuation index (FLU), para-delocalization index (PDI), PDIπ, and multicenter delocalization index (MCI).
- Assessment of electron density-derived indices: π contribution of electron localization function (ELFπ) and localized orbital locator (LOLπ).
- Application of reactivity indices: para-linear response (PLR), Shannon entropy, Fisher information, and Ghosh-Berkowitz-Parr (GBP) entropy.
Main Results:
- Delocalization-based indicators demonstrate high sensitivity to minor variations in aromaticity.
- Reactivity criteria serve as valuable complementary tools for studying aromaticity.
- Magnetic criteria (ring current strength, NICS(1)) were used for comparison.
Conclusions:
- Multiple indicators are essential for a thorough understanding of aromaticity.
- Delocalization and reactivity indices provide complementary insights into aromaticity.
- This approach enhances the study of aromaticity in diverse chemical systems.
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