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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Improved Photon-to-Current Conversion Efficiency with a Nanoporous p-Type NiO Electrode by the Use of a Sensitizer-Acceptor Dyad
Ana Morandeira,Jérôme Fortage,Tomas Edvinsson,Loïc Le Pleux,Errol Blart,Gerrit Boschloo,Anders Hagfeldt,Leif Hammarström,Fabrice Odobel +8 more
TL;DR: In this paper, a peryleneimide sensitizer and a covalently linked perylene-naphthalenediimide dyad were characterized by absorption and emission spectroscopies, electrochemistry, and spectroelec.
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Photoredox catalysts based on earth-abundant metal complexes
TL;DR: In this paper, a critical review focusses on Earth-abundant metal complexes as potential replacement photocatalysts and summarizes the use of photoactive Cu(I), Zn(II), Ni(0), V(V), Zr(IV), W(0, W(VI), Mo( 0), Cr(III), Co(III) and Fe(II) complexes in photoredox reactions.
Book ChapterDOI
Photoinduced electron and energy transfer in polynuclear complexes
TL;DR: The photochemistry and photophysics of polynuclear transition metal complexes is a new and rapidly developing area of inorganic photochemistry as discussed by the authors, characterized by the widespread occurrence of intramolecular, intercomponent electron and energy transfer processes.
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CHEMISTRY OF SINGLET OXYGEN—XXVI. PHOTOOXYGENATION OF PHENOLSy†
TL;DR: In this article, a charge transfer mechanism for quenching of singlet oxygen by phenols is proposed, which is shown to have some charge in the quench step.
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Chemosensory Performance of Molecularly Imprinted Fluorescent Conjugated Polymer Materials
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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.