Regulating Reversible Untwisting and Twisting Motions in Helical Dynamic Molecular Crystals DOI

Xiaodong Qiu,

Lin Chen, Jun Hou

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: April 17, 2025

Dynamic molecular crystals with a desirable morphology and controllable responses to external stimuli are highly desired but remain challenging. Here, we present new photoactive crystal (MCA) featuring naphthalene backbone linked vinyl structure an asymmetric tail. It can undergo reversible head-to-tail [2 + 2] photodimerization under visible light illumination heating. Helicoidally twisted crystalline fibers be easily prepared by drop-casting MCA ethanol solution onto glass surface. The thread length fiber width regulated changing the solvent evaporation temperature. An untwists upon irradiation twists back mild heating due dissociation of metastable photodimer (d-MCA), enabling reverse transformation. Crystallinity overall helical reserved well during untwisting twisting cycles, allowing multiple repetitions dynamic motions. Under interval excitation continuous heating, perform cyclical untwisting-twisting motions over 200 times for 5 h. amount significantly affects photoresponse, resulting in fully partial twisting, or complete at different dimer fractions. We found that about 10% d-MCA is enough drive circular movements. Higher photoproduct conversion makes prone fatigue lose cyclic responses. Our results provide excellent example fabricating organic soft robotics photoactuators based on spiral

Language: Английский

Mechanical Twisting-Induced Enhancement of Second-Order Optical Nonlinearity in a Flexible Molecular Crystal DOI
Zhihua Wang,

Wenqing Han,

Bona Fu

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 7, 2025

Flexible molecular crystals are essential for advancing smart materials, providing unique functionality and adaptability applications in next-generation electronics, pharmaceuticals, energy storage. However, the optical of flexible have been largely restricted to linear optics, with nonlinear (NLO) properties rarely explored. Herein, we report on application mechanical twisting second-order optics. The crystal formed through self-assembly model compound 9-anthraldehyde (AA) features an intrinsic chiral noncentrosymmetric structure, demonstrating high efficiency second harmonic generation (SHG) NLO circular dichroism, which could be greatly enhanced by macroscopic twisting. anisotropic stacking imparts AA flexibility combined elastic bending plastic isochiral enhance SHG intensities order magnitude depending their M- or P-configuration. Meanwhile, dichroism factor gSHG-CD twisted is increased, achieving highest reported anisotropy among organic materials. These boosted performances intensity chiroptical response expected expand photonic crystals.

Language: Английский

Citations

1
Effect of Mechanical Properties and Photoluminescence in Elastic Crystals Triggered by Substituent Regioisomerism DOI
Qiang Zhao,

Dongqing Lin,

Xun Fu

et al.

Crystal Growth & Design, Journal Year: 2025, Volume and Issue: 25(5), P. 1448 - 1456

Published: Feb. 13, 2025

Deformable organic photoluminescent crystals are a kind of fundamental material to exploit cutting-edge flexible optoelectronic devices. However, the realization that modulation mechanical and properties is difficult due structural properties, relationships for bendable molecular remain unclear, especially between packing, photoluminescence (PL). Herein, we report different supramolecular structures intermolecular π···π stacking via substituent regioisomerism effect (SRIE), based on three crystalline dicarbazol-9-yl-based pyrazine regioisomers para-, meta-, ortho-convergent substitutions (p-DCzP, m-DCzP, o-DCzP, respectively). We discover elasticity p-DCzP m-DCzP benefit from one-dimensional chains carbazole (Cz) units, while brittleness o-DCzP results multidirectional Cz units. Molecular dynamics (MD) simulations suggest energy beneficial reducing noncovalent interaction stabilizing aggregation structures. In addition, such in elastic can vanish aggregation-caused quenching maintain higher quantum yields blue emission dilute solutions crystals. This research reveals SRIE believe this work will provide new perspectives development functional crystal materials.

Language: Английский

Citations

0
Organic Self‐Healing Single Crystals DOI Open Access
Jiahui Zhang, Jun Tao, Zi‐Shuo Yao

et al.

Chemistry - An Asian Journal, Journal Year: 2025, Volume and Issue: unknown

Published: Feb. 18, 2025

Abstract Self‐healing single crystals, which possess the ability to recover from damage, represent an emerging filed within dynamic single‐crystal materials. These materials not only deepen our understanding of flexible structures inherent in crystals but also offer a novel pathway for development smart materials, including soft robots, microelectronic devices, and optical devices. In this perspective, we provide comprehensive summary recent advancements organic self‐healing highlighting various mechanisms, typical molecular structures, testing methods utilized investigate these We hope that systematic overview field will significantly contribute advancement crystal as new class molecular‐based functional particularly integration properties with innovative optoelectronic functionalities.

Language: Английский

Citations

0
Self-Regulating Photoactuation of Molecular Crystals Based on Halogenstyrylquinoxalines DOI

Xiqiao Yang,

Shuting Dai,

Jingbo Sun

et al.

Crystal Growth & Design, Journal Year: 2025, Volume and Issue: unknown

Published: March 26, 2025

Language: Английский

Citations

0
Regulating Reversible Untwisting and Twisting Motions in Helical Dynamic Molecular Crystals DOI

Xiaodong Qiu,

Lin Chen, Jun Hou

et al.

Journal of the American Chemical Society, Journal Year: 2025, Volume and Issue: unknown

Published: April 17, 2025

Dynamic molecular crystals with a desirable morphology and controllable responses to external stimuli are highly desired but remain challenging. Here, we present new photoactive crystal (MCA) featuring naphthalene backbone linked vinyl structure an asymmetric tail. It can undergo reversible head-to-tail [2 + 2] photodimerization under visible light illumination heating. Helicoidally twisted crystalline fibers be easily prepared by drop-casting MCA ethanol solution onto glass surface. The thread length fiber width regulated changing the solvent evaporation temperature. An untwists upon irradiation twists back mild heating due dissociation of metastable photodimer (d-MCA), enabling reverse transformation. Crystallinity overall helical reserved well during untwisting twisting cycles, allowing multiple repetitions dynamic motions. Under interval excitation continuous heating, perform cyclical untwisting-twisting motions over 200 times for 5 h. amount significantly affects photoresponse, resulting in fully partial twisting, or complete at different dimer fractions. We found that about 10% d-MCA is enough drive circular movements. Higher photoproduct conversion makes prone fatigue lose cyclic responses. Our results provide excellent example fabricating organic soft robotics photoactuators based on spiral

Language: Английский

Citations

0