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Optically active molecular materials, such as organic conjugated polymers and biological systems, are characterized by strong coupling between electronic and vibrational degrees of freedom. Typically, simulations must go beyond the Born-Oppenheimer approximation to account for non-adiabatic coupling between excited states. Indeed, non-adiabatic dynamics is commonly associated with exciton dynamics and photophysics involving charge and energy transfer, as well as exciton dissociation and charge recombination. Understanding the photoinduced dynamics in such materials is vital to providing an accurate description of exciton formation, evolution, and decay. This interdisciplinary field has matured significantly over the past decades. Formulation of new theoretical frameworks, development of more efficient and accurate computational algorithms, and evolution of high-performance computer hardware has extended these simulations to very large molecular systems with hundreds of atoms, including numerous studies of organic semiconductors and biomolecules. In this Review, we will describe recent theoretical advances including treatment of electronic decoherence in surface-hopping methods, the role of solvent effects, trivial unavoided crossings, analysis of data based on transition densities, and efficient computational implementations of these numerical methods. We also emphasize newly developed semiclassical approaches, based on the Gaussian approximation, which retain phase and width information to account for significant decoherence and interference effects while maintaining the high efficiency of surface-hopping approaches. The above developments have been employed to successfully describe photophysics in a variety of molecular materials.The emergence, amplification, and manipulation of chiroptical activity in self-assembled nanostructures, including circularly polarized absorbance and luminescence (CPL), remain considerable challenges. Here, we report the high-throughput synthesis of nanostructures with finely tailored chiroptical activities. Two fully π-conjugated benzimidazoles formed H-bonded complexes with natural hydroxyl acids (tartaric acid and mandelic acid), which self-assembled into diversified macroscopically chiral nanostructures. Synergistic coassembly allows for the emergence of Cotton effects and CPL with high dissymmetry g-factors (gabs up to 8 × 10-3, glum up to 3 × 10-3). The tartaric acid coassembled system exhibits enantiomer-independent left-handed CPL, which transforms into a cooperative ternary coassembly appended with enantiomer-resolved CPL with extended emission wavelength upon selective transition metal ion chelation. This H-boned coassembly system provides a vast number of chiral nanostructures with flexibly tuned Cotton effects and CPL, which also behaves as a selective chiroptical sensor to metal ions.Recently, wearable and flexible pressure sensors have sparked tremendous research interest, and considerable applications including human activity monitoring, biomedical research, and artificial intelligence interaction are reported. MAPK inhibitor However, the large-scale preparation of low-cost, high-sensitivity piezoresistive sensors still face huge challenges. Inspired by the specific structures and excellent metal conductivity of a family of two-dimensional (2D) transition-metal carbides and nitrides (MXene) and the high-performance sensing effect of human skin including randomly distributed microstructural receptors, we fabricate a highly sensitive MXene-based piezoresistive sensor with bioinspired microspinous microstructures formed by a simple abrasive paper stencil printing process. The obtained piezoresistive sensor shows high sensitivity (151.4 kPa-1), relatively short response time ( less then 130 ms), subtle pressure detection limit of 4.4 Pa, and excellent cycle stability over 10,000 cycles. The mechanism of the high sensitivity of the sensor is dynamically revealed from the structural perspective by means of in situ electron microscopy experiment and finite element simulation. Bioinspired microspinous microstructures can effectively improve the sensitivity of the pressure sensor and the limit of the detectable subtle pressure. In practice, the sensor shows great performance in monitoring human physiological signals, detecting quantitatively pressure distributions, and remote monitoring of intelligent robot motion in real time.Proton-transfer photopolymerization through the thiol-epoxy "click" reaction is shown to be a versatile new method for the fabrication of micro- and nanosized polymeric patterns. In this approach, complexation of a guanidine base, diazabicycloundecene (DBU), with benzoylphenylpropionic acid (ketoprofen) generates a photolabile salt. Under illumination at a wavelength of 365 nm, the salt undergoes a photodecarboxylation reaction to release DBU as a base. The base-catalyzed ring opening reaction then creates cross-linked poly(β-hydroxyl thio-ether) patterns. The surface chemistry of these patterns can be altered through alkylation of the thio-ether linkages. For example, a reaction with bromoacetic acid produces a hitherto unknown sulfonium/carboxylate-based zwitterionic motif that endows antibiofouling capacity to the micropatterns.We investigated whether the relatively Lewis basic imidazole-2-thiones could be used to substitute water ligands bound to f-element cations and generate f-element soft donor complexes. Reactions of 1,3-diethylimidazole-2-thione (C2C2ImT) with Nd(NO3)3·6H2O and UO2Cl2·3H2O led to the isolation of the anhydrous thione complexes Nd(NO3)3(C2C2ImT)3 and UO2Cl2(C2C2ImT)2, characterized by single crystal X-ray diffraction. Differences in the strength of metal-thione interactions have been examined by means of the crystal structure analysis and density functional theory (DFT) calculations. The C2C2ImT ligands were found to be affected by both coordination and noncovalent interactions, making it impossible to deconvolute the effects of one from the other. Calculated partial atomic charges indicated greater ligand-to-metal charge transfer in the [UO2]2+ complex, indicative of a stronger interaction. The reactivity of C2C2ImT demonstrates its usefulness in the preparation of f-element soft donor complexes from readily available hydrates that could be useful intermediates for promoting the coordination and studying the effects of soft donor anions.

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