Journal ArticleDOI
Kinetics of Fluorescence Quenching by Electron and H‐Atom Transfer
Dieter Rehm,Albert Weller +1 more
TLDR
In this article, the rate constants of 60 typical electron donor-acceptor systems have been measured in de-oxygenated acetonitrile and are shown to be correlated with the free enthalpy change, ΔG23, involved in the actual electron transfer process.Abstract:
Fluorescence quenching rate constants, kq, ranging from 106 to 2 × 1010 M−1 sec−1, of more than 60 typical electron donor-acceptor systems have been measured in de-oxygenated acetonitrile and are shown to be correlated with the free enthalpy change, ΔG23, involved in the actual electron transfer process
in the encounter complex and varying between + 5 and −60 kcal/mole. The correlation which is based on the mechanism of adiabatic outer-sphere electron transfer requires ΔG≠23, the activation free enthalpy of this process to be a monotonous function of ΔG23 and allows the calculation of rate constants of electron transfer quenching from spectroscopic and electrochemical data.
A detailed study of some systems where the calculated quenching constants differ from the experimental ones by several orders of magnitude revealed that the quenching mechanism operative in these cases was hydrogen-atom rather than electron transfer.
The conditions under which these different mechanisms apply and their consequences are discussed.read more
Citations
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Journal ArticleDOI
A general synthetic route to 3,5-substituted boron dipyrromethenes: applications and properties.
TL;DR: An efficient protocol for the direct synthesis of 3-substituted and 3,5-disubstituting BODIPY derivatives via electrophilic attack with NBS was developed and various substituents like ethers, sugar, hydroxyl, thiophene, sulfur, azide, tertiary amines, alkyne, vinyl, or phosphonate groups were obtained in moderate to excellent yields.
Journal ArticleDOI
Aggregation-Induced Emission Active Donor–Acceptor Fluorophore as a Dual Sensor for Volatile Acids and Aromatic Amines
TL;DR: The present study paves the way, for the first time, towards AIE driven dual stimuli response in indeno-pyrrole based D-A fluorophores as a dual sensor for volatile acids and aromatic amines.
Journal ArticleDOI
Supramolecular Donor–Acceptor Assembly Derived from Tetracarbazole–Zinc Phthalocyanine Coordinated to Fullerene: Design, Synthesis, Photochemical, and Photoelectrochemical Studies
TL;DR: In this paper, a functional photosynthetic antenna reaction center mimicking donor-acceptor polyad was designed, synthesized, and characterized, which was comprised of four entities of carbazole covalently linked to the macrocycle periphery of a zinc phthalocyanine (ZnPc).
Journal ArticleDOI
Covalently Linked Porphyrin–La@C82 Hybrids: Structural Elucidation and Investigation of Intramolecular Interactions
Lai Feng,Zdenek Slanina,Satoru Sato,Kenji Yoza,Takahiro Tsuchiya,Naomi Mizorogi,Takeshi Akasaka,Shigeru Nagase,Nazario Martín,Dirk M. Guldi +9 more
TL;DR: Three isomeric covalently linked 5,10,15,20-tetraphenylporphyrin (H2Por)–La@C82 hybrids are presented, including their synthesis, electrochemistry, and spectroscopic and computational studies.
Journal ArticleDOI
Photocatalytic Water Splitting with the Acridine Chromophore: A Computational Study.
TL;DR: Computational results indicate that the H2O molecule in the acidine-H2O complex can be dissociated into H(•) and OH( •) radicals by the absorption of two visible/ultraviolet photons.
References
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Journal ArticleDOI
On the Theory of Oxidation‐Reduction Reactions Involving Electron Transfer. I
TL;DR: In this paper, a mechanism for electron transfer reactions is described, in which there is very little spatial overlap of the electronic orbitals of the two reacting molecules in the activated complex, and a quantitative theory of the rates of oxidation reduction reactions involving electron transfer in solution is presented.
Journal ArticleDOI
Chemical and Electrochemical Electron-Transfer Theory
TL;DR: In this article, a review of electron transfer reactions is presented, focusing on the absence of bond rupture in the reaction step, which is a unique feature of purely electron-transfer reactions.
Journal ArticleDOI
Polarographic Oxidation Potentials of Aromatic Compounds
E. S. Pysh,N. C. Yang +1 more
TL;DR: In this article, the oxidation half-wave potentials of fifty-three organic compounds were determined in acetonitrile at a rotating Pt electrode, and these values were correlated with ionization potentials, with interaction energies of charge transfer complexes with trinitrofluorenone, with Huckel coefficients of the resonance integral in the expression for the highest occupied molecular orbital energy level, and with pabsorption band spectra.
Journal ArticleDOI
Electron-transfer and complex formation in the excited state
TL;DR: In this paper, a broad structureless emission band about 5000 cm1 was observed to increase with increasing electron donor concentration at the expense of the fluorescence intensity of the hydrocarbon, thereby following the same Stern-Volmer-type relation as does the well known excimer fluorescence.