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A combination of flexibility and room temperature phosphorescence (RTPR) in organic crystals is in high demand due to various applications from bio-medical to organic photonic circuit technologies. However, flexible RTPR crystals are scarce. We report the design and synthesis of novel flexible microcrystals of (Z)-3-(4-(10H-phenothiazin-10-yl)phenyl)-2-(3,5-bis(trifluoromethyl)phenyl)acrylonitrile (PTX-2CF3), exhibiting a phosphorescence lifetime of 658 μs and λmax ≈ 530 nm. The structural basis for the mechanical flexibility and mechanophotonic aspects of the PTX-2CF3 crystals is studied in detail.

Ambient pressure chemical vapour deposition of 5,5'-bis((2-(trifluoromethyl)phenyl)ethynyl)-2,2'-bithiophene provides ultrapure needle-shaped crystals. The crystal's supramolecular structure consists of an array of hydrogen bonds and π-π interactions leading to anisotropic arrangements. The cyan emitting crystals exhibit an optical waveguiding tendency with guided polarised optical emissions due to anisotropic molecular arrangements.

Time-dependent monitoring of aggregation-induced fluorescence of a model compound namely, (Z)-3-(3',5'-bis(trifluoromethyl)-[1,1'-biphenyl]-4-yl)-2-(4-bromophenyl)acrylonitrile unearth hitherto unknown molecular level events such as onset of molecular aggregation, their growth, size, and diffusion dynamics. The presented generalized approach can also be extended to in situ monitoring and controlling of various biological aggregation processes down to a single-cell level and all aspects of materials chemistry, as well.

The dark-orange monomer single crystals of 1,1′-dioxo-1H-2,2′-biindene-3,3′-diyldidodecanoate (BIT-dodeca2) convert to a transparent single-crystalline polymer (PBIT-dodeca2) material via a single-...

Optical green emitting microresonators with high values of nonlinearity are desired for high optical up-conversion energy storage and lasing applications. Here we report on the synthesis of benzyla...

Organic micro-heterostructures (MHS) with dual optical emissions are essential to produce miniaturized optical waveguides for wavelength division multiplexing technologies. The bimolecular MHS produced by solution-based bottom-up self-assembly technique often leads to poor surface smoothness, edge imperfection, defects, and unwanted thin films deposits. Conversely, sequential sublimation technique at ambient pressure facilitates effective integration of α-perylene micro-square with dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl) 4H-pyran (DCM) microrods in an epitaxial manner to produce MHS. The obtained DCM/perylene MHS act as optical waveguides to produce red (λmax ≈670 nm) or/and yellow (λmax ≈607 nm) dual optical outputs via an energy transfer mechanism depending upon the heterostructures geometry and optical excitation positions. The presented dual-color emitting MHS optical waveguides are essential for the integrated nano-photonic and optoelectronic device structures.

One-pot photocatalytic synthesis of 2-substituted benzimidazoles from 2-nitroanilines with different alcohols by combined redox cyclization reaction using TiO2-P25 is reported. The reaction, when performed with ethanol, gives 2-methylbenzimidazole as a single product. However, in a mixture of ethanol and water (1:1), it gives both 2-methylbenzimidazole and 1-ethyl-2-methylbenzimidazole. The products have been characterized by Fourier transorm–infrared, 1H NMR, 13CNMR, and gas chromatography–mass spectrometry analysis. TiO2-P25 behaves as a combined redox photocatalyst by reducing 2-nitroaniline and oxidizing alcohols simultaneously under ultraviolet light. Easy product isolation under mild conditions and good yield make this one-pot synthesis ecofriendly.

Silver-loaded TiO2 (Ag–TiO2) and acidic clay (K10 montmorillonite) composite photocatalyst has been successfully applied for the light-induced conversion of o-phenylenediamine (OPD) and its derivat...

One-pot photocatalytic synthesis of 2-substituted benzimidazoles from 2-nitroanilines with different alcohols by combined redox cyclization reaction using TiO2-P25 is reported. The reaction, when performed with ethanol, gives 2-methylbenzimidazole as a single product. However, in a mixture of ethanol and water (1:1), it gives both 2-methylbenzimidazole and 1-ethyl-2-methylbenzimidazole. The products have been characterized by Fourier transorm–infrared, 1H NMR, 13CNMR, and gas chromatography–mass spectrometry analysis. TiO2-P25 behaves as a combined redox photocatalyst by reducing 2-nitroaniline and oxidizing alcohols simultaneously under ultraviolet light. Easy product isolation under mild conditions and good yield make this one-pot synthesis ecofriendly.

Aqueous solution containing two additives, silver nitrate (AgNO(3)) and sodium salt of N-cholyl amino acid were irradiated by sunlight for the synthesis of spherical shaped AgNPs without the need for an additional stabilizer or capping agent. Variations of N-cholyl amino acid concentration provided good control over the morphology of the AgNPs, while the carboxylate group of bile salt reduced the Ag(+) ions and the amide group binds strongly to the surface of the NPs. The optical properties, morphology of the AgNPs were characterized by UV-visible, transmission electron microscopy (TEM) and dynamic light scattering (DLS) studies. The interaction of N-cholyl amino acid on the AgNPs surface was studied using cyclic voltammetry and FT-IR techniques. The reduction process was completed within 5 min and the synthesized AgNPs were stable for more than 6 months. The possible mechanism of N-cholyl amino acid on the reduction and stabilization of AgNPs is also discussed. The antimicrobial activity of N-cholyl amino acid capped AgNPs against Escherichia coli, Staphylococcus aureus and Pseudomonas aeroginosa using Mueller Hinton broth and the antifungal activity against Candida albicans, Candida krusei and Candida tropicalis using RPMI broth were determined by MIC studies as per CLSI guidelines.

The title catalyst is successfully applied to the synthesis of benzimidazoles using solar light or UV-A.