Electroabsorption studies of ruthenium(II) tris(phenanthroline) show that a substantial change in dipole moment (|Delta&mgr;| = 6.7 +/- 1 D) accompanies ground state to "singlet" metal-to-ligand charge transfer (MLCT) excited-state formation. The change is nearly identical to that reported for the 2,2'-bipyridine analogue (Oh; et al. J.Am. Chem. Soc. 1989, 111, 1130). Since both species lack ground-state dipole moments, the finite values for Delta&mgr; are diagnostic of intrinsic charge localization in the excited states. The nominally triplet transition for the phenanthroline complex also involves the formation of a charge localized state. The combined results are inconsistent, therefore, with an alternative "delocalized" charge transfer excited-state interpretation suggested by time-resolved resonance Raman studies of the tris(phenanthroline) complex.
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Angew Chem Int Ed Engl
January 2025
Stomatological Hospital of Chongqing Medical University, 426 SONGSHI NORTH RAOD, YUBEI DISTRICT, 401147, chongqing, CHINA.
Photothermal therapy (PTT) demonstrates significant potential in cancer treatment, wound healing, and antibacterial therapy, with its efficacy largely depending on the performance of photothermal agents (PTAs). Metal-phenolic network (MPN) materials are ideal PTA candidates due to their low cost, good biocompatibility and excellent ligand-to-metal charge transfer properties. However, not all MPNs exhibit significant photothermal properties, and the vast chemical space of MPNs (over 700,000 potential combinations) complicates the screening of high-photothermal materials.
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January 2025
Institute of Functional Nano and Soft Materials (FUNSOM), Jiangsu Key Laboratory for Carbon-Based Functional Materials and Devices, Soochow University, Suzhou, 215123, P. R. China.
Gold (Au) nanoclustersare promising photocatalysts for biomedicine, sensing, and environmental remediation. However, the short carrier lifetime, inherent instability, and unclear charge transfer mechanism hinder their application. Herein, the Au nanoclusters decorated with three different isomers of o-Aminophenol, m-Aminophenol, and p-Aminophenol are synthesized, namely o-Au, m-Au, and p-Au, which achieve efficient hydrogen peroxide (HO) photoproduction through two-step one-electron oxygen reduction reaction (ORR).
View Article and Find Full Text PDFJ Phys Chem Lett
January 2025
Huygens-Kamerlingh Onnes Laboratory, Niels Bohrweg 2, 2333 CA Leiden, The Netherlands.
Fluorescence spectra of single terrylene molecules adsorbed on hexagonal boron nitride flakes were recorded at cryogenic temperatures. The pure electronic transitions of terrylene molecules are spread over a broad energy scale from 570 to 610 nm. Surprisingly, peaks in the vibrationally resolved fluorescence spectrum show intensity variations of ≤20-fold between molecules.
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January 2025
Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati, 781039, India.
Image-guided photodynamic therapy is acknowledged as one of the most demonstrative therapeutic modalities for cancer treatment because of its high precision, non-invasiveness, and improved imaging ability. A series of purely organic photosensitizers denoted as BTMCz, BTMPTZ, and BTMPXZ, have been designed and synthesized and are found to exhibit both thermally activated delayed fluorescence and aggregation-induced emission simultaneously. Experimental and theoretical studies are combined to reveal that modulation of the donor of the photosensitizer enables distinct thermally activated delayed fluorescence via a second-order spin-orbit perturbation mechanism involving lowest singlet charge-transfer and higher-lying triplet locally excited states, respectively.
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January 2025
Research Institute for Sustainable Energy (RISE), TCG-CREST, Salt Lake, Kolkata, 700091, India.
Advancing next-generation battery technologies requires a thorough understanding of the intricate phenomena occurring at anodic interfaces. This focused review explores key interfacial processes, examining their thermodynamics and consequences in ion transport and charge transfer kinetics. It begins with a discussion on the formation of the electro chemical double layer, based on the GuoyChapman model, and explores how charge carriers achieve equilibrium at the interface.
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