2,4-Diamino-6-phenyl-1,3,5-triazines carrying a single oligo(ethylene oxide) (EO) chain form an optically isotropic mesophase composed of a conglomerate of macroscopic chiral domains with opposite sense of chirality even though the constituent molecules are achiral. This mesophase was proposed to result from the helical packing of hydrogen-bonded triazine aggregates, providing long-range chirality synchronization. The results provide first evidence for macroscopic achiral symmetry breaking upon conglomerate formation in an amorphous isotropic phase formed by hydrogen-bonded associates of simple N-heterocycles that are related to prebiotic molecules.
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http://dx.doi.org/10.1002/anie.201609252 | DOI Listing |
J Am Chem Soc
January 2025
Key Laboratory of Colloid and Interface Chemistry, Ministry of Education, School of Chemistry and Chemical Engineering, Shandong University, Jinan 250100, P. R. China.
Chirality epitomizes the sophistication of chemistry, representing some of its most remarkable achievements. Yet, the precise synthesis of chiral structures from achiral building blocks remains a profound and enduring challenge in synthetic chemistry and materials science. Here, we demonstrate that achiral colloidal nanocrystals, including Au and Ag nanocrystals, can assemble into long-range-ordered helical assemblies with the assistance of chiral molecules.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Center for Soft Condensed Matter Physics and Interdisciplinary Research, Soochow University, Suzhou 215006, China.
We show that spontaneous density segregation in dense systems of aligning circle swimmers is a condensation phenomenon at odds with the phase separation scenarios usually observed in two-dimensional active matter. The condensates, which take the form of vortices or rotating polar packets, can absorb a finite fraction of the particles in the system, and keep a finite or slowly growing size as their mass increases. Our results are obtained both at particle and continuous levels.
View Article and Find Full Text PDFAdv Mater
December 2024
Shaanxi Joint Lab of Graphene, State Key Lab Incubation Base of Photoelectric Technology and Functional Materials, International Collaborative Center on Photoelectric Technology and Nano Functional Materials, Institute of Photonics & Photon-Technology, Northwest University, Xi'an, 710069, P. R. China.
Bulk photovoltaic effect (BPVE) can break the Shockley-Queisser limit by leveraging the inherent asymmetry of crystal lattice without a junction. However, this effect is mainly confined to UV-vis spectrum due to the wide-bandgap nature of traditional ferroelectric materials, thereby limiting the exploration of the infrared light-driven efficient BPVE. Herein, giant two-photon absorption (TPA) driven BPVE is uncovered from visible to infrared in ferroelectric α-InSe utilizing wavelength-tunable terahertz (THz) emission spectroscopy.
View Article and Find Full Text PDFAngew Chem Int Ed Engl
November 2024
State Key Lab of Metal Matrix Composites, School of Materials Science and Engineering, Shanghai Key Laboratory for Molecular Engineering of Chiral Drugs, Shanghai Jiao Tong University, 800 Dongchuan Road, 200230, Shanghai, P. R. China.
The synergetic evolution of multiple chiral structures stemmed from same building units is ubiquitous in nature and vital to living systems, but achieving it in artificial systems remains a challenge. Herein, we report a methanol-water mediated dual assembly pathway strategy for simultaneous construction of P and M helices in one-component chiral system. The conformation of l-phenylaniline derivates (LBpyF) is controlled to folded state in CHOH due to the hydrogen bonds as well as C-H⋅⋅⋅π interaction between LBpyF and CHOH.
View Article and Find Full Text PDFAdv Mater
December 2024
Key Laboratory of Flexible Electronics & Institute of Advanced Materials, Nanjing Tech University, 30 South Puzhu Road, Nanjing, 211816, China.
Organic room-temperature phosphorescence (RTP) featuring circularly polarized luminescence (CPL) is highly valuable in chiroptoelectronics, but the trade-off issue between luminescence efficiency (Φ) and dissymmetry factor (g) is still challenging to be solved. Here, chiroptical ionic crystals (R/S-DNP) are constructed through ionization-induced assembly, in which isolated chromophore of carboxylic anion is tightly confined by the surrounding chiral counterions. The long-range ordered and chiral counterions with asymmetric stacking are closely connected with isolated chromophores for molecular assembly via high-density electrostatic interactions, thus enabling the simultaneous realization of excellent single-molecule RTP emission and efficient chirality transfer.
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