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An Electrochemical Cholesteric Liquid Crystalline Device for Quick and Low-Voltage Color Modulation
Published on: February 27, 2019
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Tuning of Optoelectronic Properties in Oligo(phenyleneethynylene)-Based Cocrystals through Modulation of
Sumayya Kuttiyullathil1, Sanal Vasantha Sudhakaran1, David Stephen Arputharaj2
1Department of Chemistry, Farook College (Autonomous), Research Centre of University of Calicut, Kozhikode, Kerala 673632, India.
ACS Omega
|November 17, 2025
Summary
Organic multicomponent cocrystals offer tunable semiconducting properties for optoelectronics. This study synthesized oligo-(phenyleneethynylene) (OPE) cocrystals with TCPN and TCNB, revealing their dependence on molecular packing and charge-transfer interactions.
Area of Science:
- Materials Science
- Organic Electronics
- Solid-State Chemistry
Background:
- Organic multicomponent cocrystals are promising for solid-state optoelectronic devices.
- Tuning electronic and optical properties is crucial for advanced applications.
Purpose of the Study:
- To design and synthesize oligo-(phenyleneethynylene) (OPE) derivative cocrystals with TCPN and TCNB.
- To investigate the influence of molecular packing and charge-transfer interactions on optical properties.
- To explore the tunability of electronic properties in mixed-stacked systems.
Main Methods:
- Synthesis of OPE derivative and its cocrystals with TCPN and TCNB.
- Single-crystal X-ray diffraction for structural analysis.
- Theoretical investigation of molecular assemblies and electronic properties.
Main Results:
- Cocrystal optical properties depend on OPE geometry and charge-transfer interactions.
- Molecular packing significantly impacts photoluminescence in the crystalline state.
- Mixed-stacked systems offer greater tunability in electronic properties compared to single-component systems.
Conclusions:
- OPE-TCPN and OPE-TCNB cocrystals exhibit tunable optoelectronic properties.
- Precise modulation of band gap, charge carrier mobility, and energy levels is achievable by combining molecules with complementary electronic structures.
- These findings advance the design of organic semiconductors for optoelectronic applications.
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