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Molecules in the bulk state are typically constrained by multiple intermolecular interactions, making it challenging to develop emission‐tunable solid‐state materials. Manipulating molecular motion is essential for achieving dynamic solid‐state emissions. Herein, various emission‐tunable 4CN@polymer films are developed whose multicolor luminescence arises from different molecular motion modes within the polymer microenvironments. There are three motion modes in the films: restricted, normal, and vigorous. In the normal mode, the film emits green light, shifting to purple under UV (515–387 nm). Cooling or fuming creates a rigid environment, leading to blue emission at 426 nm. High temperatures induce vigorous motion, causing quenched emission, which can be reactivated by cooling. This mechanism underscores the significant influence of molecular motion within flexible polymers on the luminescence behavior of 4CN@polymer films, enabling multicolor emission based on environmental conditions. The wide‐range fluorescence—from purple, blue, white, green, yellow‐green to dark—indicates promising applications in multifaceted dynamic displays and information security. This study offers novel perspectives on the correlation between solid‐state molecular motion and dynamic emission. [ABSTRACT FROM AUTHOR]

Photo‐responsive organic crystals, capable of converting light energy into chemical energy to initiate conformational transitions, present an emerging strategy for developing lightweight and versatile smart materials. However, visible light‐triggered tailored guests capture and release behaviors in all‐organic solids are rarely reported. Here, we introduce a photoreactive crystalline boron‐nitrogen (B←N) host adduct with the ability to undergo [2+2] photocycloaddition upon 447 nm light exposure. This process facilitates single‐crystal‐to‐single‐crystal (SCSC) photodimerization in the mother liquor, maintaining the original B←N host structure. Weakened intermolecular interactions within the photodimer host contribute to fast guest release in air under irradiation. Furthermore, the dynamic B←N bonds enable reversible transformations between organic host adducts and adduct cocrystals under the solvent‐induced allosteric effect. As a result, four B←N host adduct crystals containing individual alkane guest are easily obtained and exhibited the ability of photo‐controlled alkane release. Therefore, the integration of photo reactivity and structural transformation within B←N host adduct enables customized capture and release of guest molecules. [ABSTRACT FROM AUTHOR]

Ru as a cocatalyst has attracted wide attention as a substitute for Pt precious metal. However, the strong interaction between Ru and H atoms reduces the efficiency of hydrogen (H2) desorption and slows the overall hydrogen evolution reaction (HER) efficiency. How to further improve the efficiency of Ru‐based cocatalyst is challenging. Herein, single‐atom Co‐ultrafine RuOx clusters codecorated TiO2 nanosheets for photocatalytic HER are synthesized using a simple hydrothermal–calcination method. Experiments and theoretical calculations demonstrate that Co atoms can serve as a specific electronic medium, promoting electron enrichment at RuOx, thereby enhancing the adsorption of H+. Moreover, the electronic state of the interaction between adjacent Co atoms and RuOx is conducive to the desorption of H2. As a result, the proposed photocatalyst system gives a classy photocatalytic HER performance. The hydrogen production rate at stationary point reaches up to 20.20 mmol g−1 h−1, and the apparent quantum yield at 365 nm is 86.5%. It is worth noting that the hydrogen production rate in seawater is as high as 9.83 mmol g−1 h−1. This work offers precise guidance to design catalysts for efficient photocatalytic H2 production from the in‐depth understanding of the electronic coupling effect of coupling active sites. [ABSTRACT FROM AUTHOR]

In this paper, a three-dimensional subspace method is proposed, in which the search direction is generated by minimizing the approximation model of the objective function in a three-dimensional subspace. The approximation model of the objective function is not unique, and alternatives can be chosen between a symmetric quadratic model and a conic model by specific criteria. Moreover, the idea of a WLY conjugate gradient method is applied to characterize the change of gradient direction between adjacent iteration points. The strategy of initial stepsize and nonmonotone line search are adopted, and the global convergence of the presented algorithm is established under mild assumptions. In numerical experiments, we use a collection of 80 unconstrained optimization test problems to show the competitive performance of the presented method. [ABSTRACT FROM AUTHOR]

In this paper, a one-parameter class of three-term conjugate gradient methods is proposed for solving large-scale unconstrained optimization problem. Based on eigenvalue study, an adaptive choice for the embedded parameter and the corresponding three-term conjugate gradient method is obtained. In addition, the convergence properties of the obtained method are studied for both convex and general function. Numerical experiments show that the proposed method has efficient and robust performance. [ABSTRACT FROM AUTHOR]