Palladium-catalyzed cross-coupling reactions between chlorinated 1,3,5-triazines (TZ) and tetrathiafulvalene (TTF) trimethyltin derivatives afford mono- and C3 symmetric tris(TTF)-triazines as donor-acceptor compounds in which the intramolecular charge transfer (ICT) is modulated by the substitution scheme on TTF and TZ and by chemical or electrochemical oxidation. The TTF-TZ-Cl2 and (SMe)2TTF-TZ-Cl2 derivatives show fully planar structures in the solid state as a consequence of the conjugation between the two units. Electrochemical and photophysical investigations, supported by theoretical calculations, clearly demonstrate that the lowest excited state can be ascribed to the intramolecular charge transfer (ICT) π(TTF)→π*(TZ) transition. The tris(TTF) compound [(SMe)2TTF]3-TZ shows fluorescence when excited in the ICT band, and the emission is quenched upon oxidation. The radical cations TTF(+•) are easily observed in all of the cases through chemical and electrochemical oxidation by steady-state absorption experiments. In the case of [(SMe)2TTF]3-TZ, a low energy band at 5000 cm(-1), corresponding to a coupling between TTF(+•) and TTF units, is observed. A crystalline radical cation salt with the TTF-TZ-Cl2 donor and PF6(-) anion, prepared by electrocrystallization, is described.
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http://dx.doi.org/10.1021/ic3027336 | DOI Listing |
Nat Nanotechnol
January 2025
Max Planck Institute for Microstructure Physics, Halle (Saale), Germany.
Magnetic random-access memory that uses magnetic tunnel junction memory cells is a high-performance, non-volatile memory technology that goes beyond traditional charge-based memories. Today, its speed is limited by the high magnetization of the memory storage layer. Here we prepare magnetic tunnel junction memory devices with a low magnetization ferrimagnetic Heusler alloy MnGe as the memory storage layer on technologically relevant amorphous substrates using a combination of a nitride seed layer and a chemical templating layer.
View Article and Find Full Text PDFJ Chem Theory Comput
January 2025
Department of Chemistry, University of Rome, Sapienza, P.le A. Moro 5, 00185 Rome, Italy.
The charge transfer (CT) reactions in nucleic acids are crucial for genome damage and repair and nanoelectronics using DNA as a molecular conductor. Previous experimental and theoretical works underlined the significance of nucleic acid structural dynamics on CT kinetics, requiring models that incorporate the dynamics of the nucleic acid, solvents, and counterions. Here, we investigated hole transfer kinetics in poly adenine single and double strands at various temperatures and the rate enhancement due to adenine-to-7-deazaadenine mutation by means of a QM/MM approach.
View Article and Find Full Text PDFTalanta
December 2024
College of Geography and Environmental Sciences, College of Chemistry and Materials Sciences, Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China. Electronic address:
Chlorpyrifos (CPF), a widely used organophosphorus pesticide, presents substantial risks to both environmental and human health due to its persistent accumulation, thereby necessitating the development of effective detection methods. Self-powered photoelectrochemical (PEC) sensors, as an innovative technology, address the limitations inherent in conventional sensors, such as susceptibility to interference and inadequate signal response. Herein, we synthesized AgS/BiOCl as a photosensitive material, employing it as a light-harvesting substrate and a signal-transducing platform to develop a self-powered PEC sensor for the detection of CPF.
View Article and Find Full Text PDFJ Colloid Interface Sci
December 2024
School of Basic Medicine, General Hospital of Ningxia Medical University, Ningxia Medical University, Yinchuan 750004, China. Electronic address:
Targeting the peculiarities of tumor tissue microenvironment different from normal tissue, such as lower pH and overexpression of hydrogen peroxide is the key to effective treatment. In this study, acid-responsive Z-scheme heterojunctions polyglycolated MoS/CoFeO (MoS = molybdenum disulfide, CoFeO = cobalt ferrite) was synthesized using a two-step hydrothermal method, designated as MSCO-PEG, guided by dual modes of photoacoustic imagine (PAI) and nuclear magnetic imaging (MRI). MSCO-PEG (PEG = polyethylene glycol) responded to the acidic environment of tumor tissues and overexpression of hydrogen peroxide to turn on multimodal synergistic treatment of tumor cells under near-infrared-II (NIR-II) illumination.
View Article and Find Full Text PDFPhys Rev Lett
December 2024
Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA.
We measure the high-intensity laser propagation throughout meter-scale, channel-guided laser-plasma accelerators by adjusting the length of the plasma channel on a shot-by-shot basis, showing high-quality guiding of 500 TW laser pulses over 30 cm in a hydrogen plasma of density n_{0}≈1×10^{17} cm^{-3}. We observed transverse energy transport of higher-order modes in the first ≈12 cm of the plasma channel, followed by quasimatched propagation, and the gradual, dark-current-free depletion of laser energy to the wake. We quantify the laser-to-wake transfer efficiency limitations of currently available petawatt-class lasers and demonstrate via simulation how control over the laser mode can significantly improve beam parameters.
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