Electric Literature of C26H24P2. So far, in addition to halogen atoms, other non-metallic atoms can become part of the aromatic heterocycle, and the target ring system is still aromatic. Compound: 1,2-Bis(diphenylphosphino)ethane, is researched, Molecular C26H24P2, CAS is 1663-45-2, about Excitation-Wavelength-Dependent and Auxiliary-Ligand-Tuned Intersystem-Crossing Efficiency in Cyclometalated Platinum(II) Complexes: Spectroscopic and Theoretical Studies.
Understanding the factors affecting the intersystem-crossing (ISC) rate constant (kISC) of transition-metal complexes is crucial to material design with tailored photophys. properties. Most of the works on ISC to date focused on the influence by the chromophoric ligand and the understanding of the ISC efficiency were mainly drawn from the steady-state fluorescence to phosphorescence intensity ratio and ground-state calculations, with only a few high-level calculations on kISC that take excited-state structural change and solvent reorganization into account for quant. comparisons with the exptl. data. In this work, a series of [Pt(thpy)X]+ complexes were prepared [Hthpy = 2-(2′-thienyl)pyridine, where X = auxiliary ligands] and characterized by both steady-state and time-resolved luminescence spectroscopies. A panel of auxiliary ligands with varying σ-donating/π-accepting character have been used. For comparison, analogs of [Pt(ppy)(P P)]+ (Hppy = 2-phenylpyridine and P P = diphosphino ligand) were also examined The [Pt(thpy)(P P)]+ complexes exhibit dual fluorescence-phosphorescence emission, with their ISC rate constants varied with the electronic characteristics of the auxiliary ligand: the more electron-donating ligand induces faster ISC from the S1 excited state to the triplet manifold. D. functional theory (DFT)/time-dependent DFT calculations of kISC(S1→T2) at the optimized excited-state geometries give excellent quant. agreement with the femtosecond time-resolved fluorescence measurements; it was revealed that the more electron-donating auxiliary ligand increases metal contributions to both occupied and virtual orbitals and decreases the energy gap of the coupling excited states, leading to a decrease in the activation energy and an increase in spin-orbit coupling. Furthermore, the ISC rate constants of [Pt(thpy)(P P)]+ complexes are found to depend on the excitation wavelengths. The deviation from Kasha-Vavilov′s rule upon photoexcitation at λexc < 350 nm is due to the ultrafast S2 → T2 and S2 → T3 ISCs, as demonstrated by the calculated τISC < 100 fs, giving hints as to why S2 → S1 internal conversion (τIC ∼ ps) is not competitive with this hyper-ISC. Control of the intersystem-crossing (ISC) rate constant is key to tailoring the emission properties of transition-metal complexes. Both spectroscopic and theor. studies of a series of cyclometalated platinum(II) complexes reveal that the ISC rate can be tuned by varying the electron-donating capability of the auxiliary ligands. Moreover, hyper-ISC from the higher-lying singlet excited state to the triplet manifold has been unveiled by theor. studies, explaining the excitation-wavelength-dependent dual fluorescence-phosphorescence emission for the present platinum(II) complexes. Here is a brief introduction to this compound(1663-45-2)Electric Literature of C26H24P2, if you want to know about other compounds related to this compound(1663-45-2), you can read my other articles.
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Chiral nitrogen ligands in late transition metal-catalysed asymmetric synthesis—I. Addressing the problem of ligand lability in rhodium-catalysed hydrosilations,
Nitrogen-Containing Ligands for Asymmetric Homogeneous and Heterogeneous Catalysis