Meta-Substituted Asymmetric Azobenzenes: Insights into Structure–Property Relationship

This article presents a comprehensive investigation into the functionalization of methoxyphenylazobenzene using electron-directing groups located at the meta position relative to the azo group. Spectroscopic analysis of meta-functionalized azobenzenes reveals that the incorporation of electron-withdrawing units significantly influences the absorption spectra of both E and Z isomers, while electron-donating functionalities lead to more subtle changes. The thermal relaxation process from Z to E result in almost twice as prolonged for electron-withdrawing functionalized azobenzenes compared to their electron-rich counterparts. Computational analysis contributes a theoretical understanding of the electronic structure and properties of meta-substituted azobenzenes. This combined approach, integrating experimental and computational techniques, yields significant insights into the structure–property relationship of meta-substituted asymmetrical phenolazobenzenes

Light-Responsive Oligothiophenes Incorporating Photochromic Torsional Switches (PTS)

We present a quaterthiophene and sexithiophene that can reversibly change their effective π-conjugation length via photoexcitation. The reported compounds make use of light-responsive molecular actuators consisting of an azobenzene attached to a bithiophene unit by both direct and linker-assisted bonding. Upon exposure to 350 nm light the azobenzene undergoes trans -to- cis isomerization mechanically inducing the oligothiophene to assume a planar conformations (extended π-conjugation). Exposure to 254 nm wavelenght promotes azobenzene cis -to- trans isomerization, forcing the thiophenic backbones to twist out of planarity (confined π-conjugation). Twisted conformations are also reached by cis -to- trans thermal relaxation with rate that increases proportionally with the conjugation length of the oligothiophene moiety. The molecular conformations of quaterthiophene and sexithiophene were characterized using steady-state UV-vis, X-ray crystallography and quantum-chemical modelling. Finally, we tested the proposed light-responsive oligothiophenes into field-effect transistors to probe the photo-induced tuning of their electronic properties

Expression of proteins of interest in food

PòsterJun

Promising Molecular Architectures for Two-Photon Probes in the Diagnosis of α-Synuclein Aggregates

The abnormal deposition of protein in the brain is the central factor in neurodegenerative disorders (NDs). These detrimental aggregates, stemming from the misfolding and subsequent irregular aggregation of α-synuclein protein, are primarily accountable for conditions such as Parkinson’s disease, Alzheimer’s disease, and dementia. Two-photon-excited (TPE) probes are a promising tool for the early-stage diagnosis of these pathologies as they provide accurate spatial resolution, minimal intrusion, and the ability for prolonged observation. To identify compounds with the potential to function as diagnostic probes using two-photon techniques, we explore three distinct categories of compounds: Hydroxyl azobenzene (AZO-OH); Dicyano-vinyl bithiophene (DCVBT); and Tetra-amino phthalocyanine (PcZnNH2). The molecules were structurally and optically characterized using a multi-technique approach via UV-vis absorption, Raman spectroscopy, three-dimensional fluorescence mapping (PLE), time-resolved photoluminescence (TRPL), and pump and probe measurements. Furthermore, quantum chemical and molecular docking calculations were performed to provide insights into the photophysical properties of the compounds as well as to assess their affinity with the α-synuclein protein. This innovative approach seeks to enhance the accuracy of in vivo probing, contributing to early Parkinson’s disease (PD) detection and ultimately allowing for targeted intervention strategies

Unveiling the significance of adduct formation between thiocarbonyl Lewis donors and diiodine for the structural organization of rhodanine-based small molecule semiconductors

Rhodanine vinyl bithiophene (BTR) was synthesized and characterized both spectroscopically and structurally. The reaction of BTR with molecular iodine led to the 1 : 1 “spoke” adduct BTR·I2, formed by interaction of the rhodanine thiocarbonyl group with a diiodine (I2) molecule. The elongation of the I–I bond in the adduct with respect to solid-state I2 and the Raman response in the low-energy region (ν = 150 cm−1) clearly indicate BTR·I2 to be a weak CT adduct. Hybrid-DFT calculations showed that the adduct formation narrowed the HOMO–LUMO gap in BTR·I2 as compared to BTR, while the extended network of secondary interactions, including type-I halogen bonds (XB), results in the formation of an extended 3D network. As a consequence, the room temperature conductivity of BTR·I2 increased with respect to BTR, testifying for a more efficient molecular packing for charge percolation, with the formation of charge carriers in the crystal being facilitated by the presence of I2. It is worth noting that the single-crystal junction device operates at room temperature, in air, and no variation of conductivity over time was observed, indicating that no loss of diiodine occurred during measurements. These results clearly indicate the formation of thiocarbonyl–diiodine CT adducts and their potential as a solid additive for modulating the organization of small molecule semiconductors

Temperature integrity sensor

The present invention relates to a temperature integrity sensor or more precisely a temperature continuity sensor of a product which needs to be kept at a temperature below its degradation temperature, such as for instance a refrigerated or frozen edible product; a pharmaceutical product such as a vaccine, or an antibiotic; or a biological-medical product such as a sample of a body fluid or tissue, or an organ. The sensor is based on RFID technology, in particular passive RFID technology

Compound for uses in optical and electrooptical devices

which can also be embedded into a conjugated oligomeric of polymeric backbone, is proposed for optical and electro optical applications

Elucidating Charge Generation in Green-Solvent Processed Organic Solar Cells

Organic solar cells have the potential to become the cheapest form of electricity. Rapid increase in the power conversion efficiency of organic solar cells (OSCs) has been achieved with the development of non-fullerene small-molecule acceptors. Next generation photovoltaics based upon environmentally benign “green solvent” processing of organic semiconductors promise a step-change in the adaptability and versatility of solar technologies and promote sustainable development. However, high-performing OSCs are still processed by halogenated (non-environmentally friendly) solvents, so hindering their large-scale manufacture. In this perspective, we discuss the recent progress in developing highly efficient OSCs processed from eco-compatible solvents, and highlight research challenges that should be addressed for the future development of high power conversion efficiencies devices

Double-channel photosystems with antiparallel redox gradients: templated stack exchange with porphyrins and phthalocyanines

We report the synthesis of multicomponent surface architectures composed of phthalocyanines (Pc), porphyrins (TPP) and naphthalenediimides (NDI). Naphthalenediimide stacks are grown first by self-organizing surface initiated disulfide-exchange polymerization (SOSIP). An oriented redox gradient driving electrons toward the surface is applied by growing electron-richer NDI stacks on top of poorer ones. Lateral stacks of porphyrins and phthalocyanines are then added by templated stack exchange (TSE). A three-component gradient is constructed to drive the holes away from the solid surface. Antiparallel gradients are found to minimize charge recombination during photocurrent generation. Templates used for stack exchange also serve as hole barriers, whereas their size has surprisingly little importance. These results demonstrate the compatibility of SOSIP-TSE technology with porphyrins and phthalocyanines, confirm the importance of oriented antiparallel gradients to minimize charge recombination, and show that electronics rather than the size matter to template stack exchange