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Push-pull heterocycles and beyond: recent developments in absorption, emission, and ICT properties.
Manel Essid1, Ehsan Ullah Mughal2
1Chemistry Department, College of Science, King Khalid University (KKU) P.O. Box 9004 Abha 61413 Saudi Arabia.
RSC Advances
|October 10, 2025
Summary
This review summarizes recent advances in heterocyclic chromophores, detailing how structural changes and solvent effects tune their optical properties. These materials show promise for next-generation optoelectronics and photonics.
Area of Science:
- Organic Materials Chemistry
- Photophysics
- Materials Science
Background:
- Heterocyclic scaffolds are crucial for advanced organic materials due to tunable electronic and photophysical properties.
- Recent research focuses on designing heterocyclic chromophores with specific absorption, emission, and charge transfer characteristics.
Purpose of the Study:
- To provide a comprehensive review of heterocyclic chromophores reported in 2024-2025.
- To analyze structure-property relationships influencing optical and electronic behaviors.
- To highlight potential applications in optoelectronics, sensing, and photonics.
Main Methods:
- Literature review of 2024-2025 publications on heterocyclic chromophores.
- Analysis of systems including indole-coumarins, 3-cyano-2-pyridones, TCBD derivatives, BODIPYs, and pyrimidine-based boron complexes.
- Correlation of structural modifications, solvent polarity, and push-pull effects with photophysical properties.
Main Results:
- Detailed examination of how structural changes impact band gaps and spectral shifts (bathochromic/hypsochromic).
- Discussion of intramolecular charge transfer (ICT) and solvent-dependent spectral shifts.
- Evaluation of fluorescence quantum yields and near-infrared (NIR) emission properties.
Conclusions:
- Structural modifications and environmental factors significantly influence the photophysical properties of heterocyclic chromophores.
- These compounds offer tunable band gaps and emission profiles for tailored applications.
- Heterocyclic chromophores are promising for advanced optoelectronic, sensing, and photonic devices.
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