ChemPhotoChem最新文献

We present Transient Absorption Processing and Analysis Software (TAPAS), an open-source, Python-based graphical platform that covers the entire transient absorption (TA) workflow, from raw data import and preprocessing to visualization, global and target fitting, and statistical evaluation. Users operate TAPAS through an intuitive, seven-tab GUI, yet all underlying modules remain accessible for inspection and extension, merging GUI convenience with script-level flexibility. The fitting engine employs just-in-time compilation via an open-source machine learning compiler ecosystem, delivering two–20-fold speed gains over established packages. Automatic differentiation and residual-based effective-sample-size calculations yield reliable confidence intervals and correlation matrices, while an integrated sampling routine provides full Bayesian posterior exploration—diagnostics which are rarely available in other TA tools. All raw, processed, and fitted data are written to standardized Hierarchical Data Format 5 containers and automatically annotated with rich metadata, ensuring complete provenance. An extended case study on Rose Bengal shows how TAPAS first reveals hidden lifetime correlations, then employs broadband global and target analysis to merge TA traces with complementary steady-state and literature data, yielding a single, self-consistent kinetic model. By uniting advanced uncertainty quantification and transparent data management within a user-friendly interface, TAPAS closes the gap between accessibility and rigorous statistical treatment in TA spectroscopy.

The Front Cover illustrates the concept of the “ESIPT machine,” symbolizing the synthesis of N-substituted imidazoles via the Debus–Radziszewski reaction. The assembly line represents the multi-component process leading to molecules that could exhibit a tunable solvent-dependent excited-state intramolecular proton transfer (ESIPT) process. More information can be found in the Research Article by J. L. Belmonte-Vázquez and co-workers (DOI: 10.1002/cptc.202500262). Illustration by Armando Navarro-Huerta.

A series of bis-diimine rhenium(I) complexes Re(NN1-OMe)−Re(NN3-OMe), containing neocuproine and methyl [2-(pyridin-2-yl)quinoline-4-carboxylate (NN1), methyl [2,2′-biquinoline]-4-carboxylate (NN2), dimethyl [2,2′-biquinoline]−4,4′-dicarboxylate (NN3) was synthesized and characterized. Utilization of the asymmetric NN1 and NN2 ligands affords two types of structural isomers, which were isolated and structurally studied by X-ray diffraction analysis in the solid state. ¹H-¹H COSY and NOESY NMR experiments confirmed preservation of the structural patterns in liquid media for the complexes under study. Alkaline hydrolysis of the ester groups in the NN# diimine ligands was performed to give the Re(NN1-OK)−Re(NN3-OK) complexes exhibiting higher water solubility that made possible to use them in biological experiments. In MeOH and aqueous media, the complexes display NIR absorption with a long wavelength band at ca. 715 nm extended up to 850 nm in the case of both forms of Re(NN3)-OX. The Re(NN3-OK) complex demonstrated stable photoacoustic signal in oxygenated blood phantoms and showed no significant toxicity with the cell viability above 80% even at concentrations of 1 mM in cell experiments with CHO-K1 cell line.

Metal–organic radical luminescent materials, as an emerging research direction in the field of optoelectronic functional materials, have attracted extensive attention due to their unique open-shell electronic structures and controllable photophysical properties. This review provides an in-depth discussion of metal–organic free radical materials from multiple perspectives, including the optical physical properties, construction strategies, metal action mechanisms, and practical applications in the field of photoelectric magnetism. Especially in terms of the interaction between metals and organic radicals as well as the applications, the specific influence of the charge-transfer process between metals and organic radicals was discussed in detail, along with the potential applications in fields such as photodriven sensing, photothermal conversion, and photoelectromagnetic coupling. Although the number of literature on metal–organic free radicals has significantly increased in recent years, most existing research articles and review articles are limited to specific metal systems and lack systematic comparison. The depth of discussion on the structure–activity relationship of the materials is insufficient, and the discussion on the application transformation path is also rather vague. This review aims to break through the above limitations, provide comprehensive references for researchers, and promote the further development of the field of metal–organic free radical luminescent materials.

The Cover Feature illustrates the formation of cycloaddition products through the key “distonic radical cation” intermediates that can be generated from a variety of redox active molecules. Various reagents, depicted as water bubbles, rise through the photoredox fountain, getting converted to their respective distonic radical cation forms. Subsequent reaction with suitable partners, leads to the formation of various cycloadducts represented by the water droplets emerging out of the fountain. More information can be found in the Review by S. Debnath and S. Maity (DOI: 10.1002/cptc.202500249). Art by Arunima Mukherjee.

The Front Cover illustrates the mode of action of Lyso-Naphth-AIE, a novel aggregation-induced emission (AIE) photosensitizer (PS) that specifically targets lysosomes. Upon light irradiation, Lyso-Naphth-AIE (white structure) generates reactive oxygen species (ROS, red spheres) through both type I and II photodynamic therapy (PDT) mechanisms, and this triggers apoptosis. Additionally, the near-infrared luminescence of the activated Lyso-Naphth-AIE enables real-time imaging. This work establishes a new approach for designing multifunctional AIE PSs for imaging-guided PDT. More information can be found in the Research Article by U. R. Gandra, M. I. Haja Mohideen, M. Magzoub and co-workers (DOI: 10.1002/cptc.202500202).

Molecular recognition of guest molecules within confined cavities enables effective modulation of their chemical and physical properties through noncovalent interactions. Because these modulated properties reflect the structural features of the host–guest assembly, the guest molecule can serve as a molecular probe to elucidate the origin of the host-induced modulation. Herein, we report the formation of a host–guest complex composed of an emissive Ir(III) complex salt and a resorcin[4]arene host, along with the photophysical modulation of the guest via noncovalent interactions with the host. NMR spectroscopic analysis reveals a 1:1 binding stoichiometry, in contrast to the previously reported 6:1 stoichiometry, because the guest is larger than the cavity of the resorcin[4]arene hydrogen-bonded hexameric capsule. This 1:1 binding mode is unambiguously confirmed by single-crystal X-ray diffraction analysis. The photoluminescent properties of the Ir(III) complex are enhanced in the presence of the host, indicating that electronic communication between the host and the guest plays a crucial role in modulating its photophysical behavior. These findings are further supported by density functional theory calculations. Overall, this article provides new insights into the photophysical dynamics of entrapped emitters and highlights the pivotal role of host–guest interactions in tuning emission properties.

Converting atmospheric nitrogen (N₂) into ammonia (NH₃) by sustainable methods presents a significant challenge in green chemistry. Photocatalytic N₂ fixation under visible light offers a promising solution, provided efficient catalysts can effectively weaken the strong N≡N bond. In this study, we present a composite photocatalyst composed of the metal–organic framework (MOF) UiO-66-NH₂ and substoichiometric tungsten oxide (W₁₈O₄₉). The oxygen vacancies in W₁₈O₄₉ extend its visible light absorption, while UiO-66-NH₂ provides a high surface area and amine-functionalized linkers that enhance light harvesting. We synthesized UiO-66-NH₂/W₁₈O₄₉ composites with varying UiO-66-NH₂ contents (30%, 50%, and 70% by weight) and evaluated their photocatalytic performance under visible-light irradiation. The 50% UiO-66-NH₂/W₁₈O₄₉ composite exhibited the highest NH₃ production rate of 420.8 μmol g⁻¹ h⁻¹, which is 27.2 times higher than that of pure UiO-66-NH₂ and 10.9 times higher than that of W₁₈O₄₉. This enhancement is attributed to the synergistic heterojunction between UiO-66-NH₂ and W₁₈O₄₉, where the MOF provides a large surface area and efficient light absorption, while W₁₈O₄₉ contributes plasmon-generated hot electrons and abundant oxygen vacancies. The composite demonstrates broadened visible-light absorption, efficient charge separation, and rapid charge transfer, thus suppressing electron–hole recombination. These results highlight the potential of the UiO-66-NH₂/W₁₈O₄₉ composite as an effective photocatalyst for solar-driven ammonia production under mild conditions.

Fluorescence sensors provide powerful platforms for real-time monitoring of viscosity due to their high sensitivity, with important implications for microscopic and cellular studies. Lipid droplets, which play central roles in cellular metabolism, represent key targets for such investigations; however, precise approaches for quantifying intracellular viscosity and polarity remain limited. To address this challenge, we developed a series of (4-methoxyphenyl) ethynyl-naphthalimide derivatives tailored for viscosity sensing and live-cell imaging. These fluorophores displayed pronounced fluorescence enhancement, with a linear emission response in glycerol solutions ranging from 60% to 100%, demonstrating high sensitivity to viscosity changes. In addition to favorable photophysical properties, they exhibited excellent biocompatibility and selective accumulation in lipid droplets, enabling real-time visualization of viscosity dynamics in live cells. Among these, probe LD-A showed superior performance: medium-viscosity environments correlated with an increased green-to-blue fluorescence intensity ratio, while high-viscosity conditions induced redshifted emissions, consistent with in vitro solvent studies. Collectively, these results establish LD-A and its analogs as promising fluorescent tools for probing viscosity variations in biological systems with high specificity and sensitivity.

In this contribution, a set of five differently substituted phenoxazines (POA) derived from a central terephthalonitrile core is investigated. Depending on incorporated electron-donating groups (-NH₂, -NMe₂, and -OMe) or electron-withdrawing groups (-NO₂ and -CN), distinctive luminescent behavior is observed, with preferred emission either in solution, in the solid-state, or in both. An in-depth assessment of the photophysical properties revealed a subtle influence of the substituents on the absorption and emission wavelengths, which correlate with the Hammett parameters, yet a strong sensitivity to the surrounding environment. Hence, solvatochromic response and aggregation studies were conducted to identify the optimal conditions for efficient emission. Absolute photoluminescence quantum yield values of up to 0.47 in tetrachloromethane and 0.33 in the solid state were determined, underscoring the impressive photophysical characteristics of the presented compounds. X-ray diffractometric analyses in combination with Hirshfeld surface evaluation were employed to elucidate the packing effects and their possible relation to the photophysical performance. Finally, density functional theory calculations provided a detailed understanding of the occurring electronic transitions and spatial localization of the natural transition orbitals.