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Hydrogen bonding interactions can decrease clar sextet character in acridone pigments
Zhili Wen1, Lucas José Karas1, Judy I-Chia Wu1
1Department of Chemistry, University of Houston, Houston, Texas 77204, USA. jiwu@central.uh.edu.
Organic & Biomolecular Chemistry
|October 28, 2021
Summary
Polarization of acridone π-systems affects Clar sextet rings, influencing electronic properties. This impacts the HOMO-LUMO gap and charge mobility in related organic materials.
Area of Science:
- Organic Chemistry
- Computational Chemistry
- Materials Science
Background:
- Acridone derivatives are important in organic electronics.
- Understanding their electronic structure is key to optimizing material properties.
- Clar sextet theory describes aromaticity in polycyclic systems.
Purpose of the Study:
- To investigate the relationship between π-system polarization and Clar sextet distribution in acridones.
- To correlate changes in Clar sextets with experimentally observed electronic properties.
Main Methods:
- Computed nucleus-independent chemical shifts (NICS).
- Contour plots of isotropic magnetic shielding (IMS).
- Gauge-including magnetically induced current (GIMIC) plots.
Main Results:
- π-system polarization in acridones perturbs the number and position of Clar sextet rings.
- A decrease in Clar sextets correlates with a narrowed HOMO-LUMO gap.
- Reduced Clar sextets are linked to increased charge mobility in solid-state assemblies.
Conclusions:
- π-system polarization is a critical factor influencing the electronic behavior of acridones.
- The findings provide a theoretical basis for understanding charge transport in quinacridone and epindolidione systems.
- This work aids in the rational design of organic electronic materials.
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