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Piecing it Together: An Additivity Scheme for Aromaticity using NICS-XY Scans
1Laboratorium für Organische Chemie, ETH Zurich, Vladimir-Prelog-Weg 2, Zurich, 8093, Switzerland.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|January 10, 2018
Summary
We developed a new method to predict aromaticity in polycyclic aromatic hydrocarbons using building blocks. This approach offers insights into aromatic character and is useful for large systems.
Area of Science:
- Organic Chemistry
- Computational Chemistry
Background:
- Aromatic compounds are widespread but their properties remain challenging to predict.
- Accurate prediction of aromaticity is crucial for understanding material properties.
Purpose of the Study:
- To introduce a novel additivity scheme for predicting the aromatic character of polycyclic aromatic hydrocarbons (PAHs).
- To provide a simple and intuitive method for constructing Nuclear Independent Chemical Shift (NICS)-XY-scans.
Main Methods:
- Developed an additivity scheme based on a small set of building blocks and combination rules.
- Applied the scheme to construct NICS-XY-scans for various one- and two-dimensional systems with six-membered rings.
- Partitioned contributions of building blocks to analyze aromatic character.
Main Results:
- Successfully demonstrated the construction of NICS-XY-scans for test systems.
- Gained insights into the distribution of ring currents and the impact of topology on aromaticity.
- Validated the scheme's ability to predict aromatic character.
Conclusions:
- The presented additivity scheme offers a new perspective on aromaticity in PAHs.
- The method is general, customizable, and particularly beneficial for investigating large and complex systems.
- NICS-XY-scans generated by this scheme have predictive utility for optoelectronic and thermochemical properties.
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