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Updated: Jul 2, 2025
06:44
From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
69.1K
Supramolecular Metal Halide Complexes for High-Temperature Nonlinear Optical Switches.
Qian Wang1, Jianbo Jin2, Zhongxuan Wang3
1Department of Chemistry, Virginia Tech, Blacksburg, Virginia 24061, United States.
Journal of the American Chemical Society
|February 23, 2024
Summary
Researchers developed new solid-state supramolecular compounds for nonlinear optical (NLO) switching. These materials maintain stable NLO switching even at high temperatures, overcoming limitations of existing NLO materials.
Area of Science:
- Materials Science
- Chemistry
- Optics
Background:
- Nonlinear optical (NLO) switching materials are crucial for sensing, photoelectronics, and photonics.
- Current solid-state NLO materials often degrade at elevated temperatures due to phase transitions.
Purpose of the Study:
- To introduce a novel class of solid-state supramolecular compounds for stable NLO switching.
- To investigate the mechanism behind reversible NLO switching in response to external stimuli.
Main Methods:
- Synthesis of solid-state supramolecular compounds: 18-Crown-6 ether@Cu2Cl4·4H2O (1·4H2O).
- Investigation of NLO switching properties under near-infrared (NIR) photoexcitation and thermal stimuli.
- Analysis of crystal structure changes and water molecule dynamics.
Main Results:
- The novel compounds exhibit reversible and stable NLO switching upon NIR photoexcitation and/or thermal stimuli.
- High second-harmonic generation (SHG) signals were observed even above 110 °C.
- Reversible release and recapture of bridging water molecules enabled precise control of SHG signals with million-fold contrast ratios.
Conclusions:
- The developed supramolecular compounds offer a promising solution for high-performance NLO switching at elevated temperatures.
- The unique structural dynamics involving bridging water molecules are key to achieving stable and controllable NLO switching.
- These materials hold potential for advanced photonic and optoelectronic applications requiring thermal stability.
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