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Showing 1 to 20 of 29 for “"MLCT"”.
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Synthesis and characterisation of ligand-bridged tungsten and chromium penta- and tetra-carbonyl complexes
… and mononuclear, [4(CO)CrDPT] complexes have MLCT transitions at 900.88 nm and 652.52 nm respectively. The dinuclear MLCT is more intense and broad and is deemed to have overlapped with the d-d transitions observed in the mononuclear complex at 909.45 nm. However, intra-ligand transitions were …
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Design, Synthesis and Spectroscopy of Highly Absorptive Chromophores Based on the Bis(tridentate)metal-ethyne-(porphinato)metal Molecular Framework for Solar Energy Conversion
… tunable potentiometric metal-to-ligand CT (MLCT) band gaps and low-lying MLCT featured highly delocalized triplet excited states. Although their 3MLCT lifetimes are short (sub-picosecond time scale) for realistic applications, this study signifies a strategy to decouple the modulation of …
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Photochemistry and Photophysics of Octahedral Ruthenium Complexes
… a lower energy metal to ligand charge transfer (MLCT) transition showing binding to DNA when irradiated at 650 nm, within the ideal PDT window of 600-850 nm.The low temperature emission and photolysis of [Ru(bpy)<sub>3</sub>]<sup>2+</sup>, cis-[Ru(bpy)<sub>2</sub>(AN)<sub>2</sub>]<sup>2+</sup>, …
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Photochemical synthesis and characterization of mono- and bi-nuclear tungsen tetracarbonyl complexes of 2,2'-biquinoline and 2,3-bis(2- pyridyl) pyrazine
… and a broad metal-to-ligand charge-transfer (MLCT). The latter bands are red-shifted in the binuclear complexes. For comparison purposes, the properties of free ligands have also been studied. The complexes have electronic spectra dominated by intense MLCT transition in the visible region of …
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Discovering the Potential of Photoluminescent Ruthenium(II) Complexes as Photodynamic Therapy Agents
… light with metal-to-ligand charge transfer (MLCT) transitions at 459 nm (16,000 M-1 cm-1 ) and 461 nm (21,000 M-1 cm-1 ), respectively. These species exhibit 3 MLCT emissions at λem = 661 nm and λem = 663 nm for 1 and 2, respectively, while the anthracene show emissions at 450 – 560 nm. The …
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Comparative Electrochemistry, Electronic Absorption Spectroscopy and Spectroelectrochemistry of the Monometallic Ruthenium Polypyridyl Complexes, [Ru(Bpy)(Dpb)2](Pf6)2, [Ru(Bpy)2(Dpb)](Pf6)2, [Ru(Bpy)2(Dpq)](Pf6)2, [Ru(Bpy)(Dpq)2](Pf6)2
… [Ru(bpy)(dpb)â ](PFâ )â : (1) the Ru (dÏ ) â dpb MLCT at 552 nm, (2) a d â d at 242 nm, a bpy Ï â Ï * at 285 nm. (3) The location of the Ru (dÏ ) â bpy MLCT peak is obscured by shoulders from 390-420 nm. (4) The strong peak at 316 nm may be dpb Ï â Ï â *, the location of the lower energy …
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Tuning the Photophysical and Biological Properties of a Series of Ruthenium-Based Chromophores and Chromophore Coupled Cisplatin Analogs with Substituted Terpyridine Ligands
… UV region and metal to ligand charge transfer (MLCT) transitions in the visible region. The Ru to dpp MLCT transitions in RuIIPtII bimetallic complexes were found to be red-shifted relative to the monometallic synthons. The MLCT transitions for [(TL)RuCl(dpp)](PF₆) and [(TL)RuCl(dpp)PtCl₂](PF₆) …
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Part I Synthesis and molecular Assemblies of d10 metal complexes bearing 9, 10-disubstituted anthracene ligand Part II Synthesis and spectroscopic studies of heterobimetallic platinum(II)-acetylide and platinum(0)-acetylene complexes
… addition, to search for complexes of low-lying MLCT excited states, the electronic spectroscopic study of a series of platinum(0)-acetylene I? complexes was carried out.
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The Effects of Nonionic Surfactants on the Tris(2,2'-Bipyridl) Ruthenium(Ii)-Tripropylamine Electrochemiluminescence System
… orbitals in the metal-to-ligand charge transfer (MLCT) excited state. These results are consistent with the hydrophobic interactions between Ru(bpy)₃²⁺ and the nonionic surfactants. There was no observable change in the fluorescence of Ru(bpy)₃²⁺ in the presence of nonionic surfactants.
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Design and Modification of Polyazine-Bridged Ru(II),Rh(III) Bimetallic and Trimetallic Supramolecular Complexes Applicable in Solar Energy Harvesting for the Photocatalytic Reduction of Water to Hydrogen
… metal-to-ligand charge transfer (MLCT) transitions in the visible. While X identity does not vary the light absorbing properties within Ru(II),Rh(III),Ru(II) trimetallics, TL identity and the number of Ru(II) LAs strongly impacts spectral coverage and the extinction coefficient. …
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A Rhodium Centered Supramolecular Complex as a Photoinitiated Electron Collector
… to the intense metal to ligand charge transfer (MLCT) absorptions observed in the visible spectrum. Electrochemical methods establish rhodium as the site of localization of the lowest lying unoccupied molecular orbital, while phosphorescence measurements are used to study electron transfer within …
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Synthesis and Study of Polyazine Bridged Mixed Metal Dyads: Electrochemical, Photophysical, and Photochemical Properties of a New Supramolecular Architecture
… display Ru(dπ)â bpm(π*) CT (MLCT) transitions at 581 nm and at 594 nm, respectively. The dpp bridged Ru,Rh bimetallic and Ru,Rh,Ru trimetallic display Ru(dπ)â dpp(π*) CT transitions at 509 nm and 518 nm, respectively. Similarly, [(bpy)2Os(dpp)RhCl2(phen)](PF6)3 absorbs …
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LUMINESCENT 2D COORDINATION NETWORKS (CNS): STRUCTURAL AND EXFOLIATION STUDIES
… guest-centered, metal-to-ligand charge transfer (MLCT), and ligand-to-metal charge transfer (LMCT). The designability of CPs enables the synthesis of novel 2D luminescent coordination polymers (LCPs) with superior photophysical properties compared to their conventional counterparts. In recent …
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Supramolecular Ru II, Pt II Complexes Bridged by 2,3,5,6-tetrakis(2-pyridyl)pyrazine (tppz)
… Spectroscopically, the Ru(dπ)⟶ tppz(π*) MLCT transitions are red-shifted relative to the monometallic synthons ([(tpy)Ru(tppz)](PF₆)₂, λ<sub>max</sub><sup>abs</sup> = 472 nm and [Ru(tppz)₂](PF₆)₂, λ<sub>max</sub><sup>abs</sup> = 478 nm) occurring in the visible region, centered at 530 and …
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Probing the Redox and Photophysical Properties of Ru(II)-Pt(II) Supramolecular Complexes as Efficient Photodynamic Therapy Agents
… region by metal-to-ligand charge transfer (MLCT) transitions at 424 nm (Ru(dπ)→ Ph₂phen(π*) 1CT) and 517 nm (Ru(dπ)→ dpp(π*) 1CT) or 600 nm (Ru(dπ)→ dpq(π*) 1CT). Steady-state and time-resolved emission spectroscopy shows that upon attaching Pt to the Ru monometallic precursor the λmaxem …
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Improving Photocatalytic Hydrogen Production of Ru,Rh,Ru Supramolecular Complexes in Aerobic Aqueous Solutions
… of the metal-to-ligand charge transfer (MLCT) excited-state under these conditions. Herein, we report the groundbreaking use of polyelectrolytes to increase efficiency of supramolecular photocatalysts in solar hydrogen production schemes under aqueous aerobic conditions. The new …
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Tuning the ground and excited state properties of a series of polymetallic tridentate complexes incorporating Ru(II) or Os(II) as the chromophore
… a lowest lying excited state that is always a MLCT state involving tpp but can be tuned to involve Ru or Os metal centers. Bimetallic systems that incorporate this tpp ligand have long lived excited states in solution at room temperature (t >100 ns). The bimetallic complex [(tpy)Ru(tpp)IrCl₃]²⁺ …
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The femtosecond m-edge approach to the photodynamics of iron(II) complexes
… into the metal-to-ligand charge transfer (MLCT) band shows that the sample undergoes the expected photoinduced conversion from its singlet ground state into its metastable quintet state. Transient response in the first 300 fs after excitation clearly shows the presence of an intermediate …
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The Design, Synthesis and Study of Mixed-Metal Ru,Rh and Os, Rh Complexes with Biologically Relevant Reactivity
… UV region and metal-to-ligand charge transfer (MLCT) transitions in the visible region of the spectrum with approximately half the absorption extinction coefficient values relative to the trimetallics in the spectrum. The Os,Rh bimetallic complex, [(bpy)2Os(dpp)RhCl2(phen)]3+, displays …
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Multimetallic Supramolecular Complexes: Synthesis, Characterization, Photophysical Studies and Applications in Solar Energy Utilization and Photodynamic Therapy
… overlapping metal to ligand charge transfer (MLCT) transitions in visible region of spectrum. Spectroelectrochemistry revealed the nature of MLCTs and helped to identify fingerprint features of complex supramolecules. Photophysical measurements include emission spectroscopy with quantum yield …
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