1. Formation of hydroxyl radicals by irradiated 1-nitronaphthalene (1NN): oxidation of hydroxyl ions and water by the 1NN triplet state
- Author
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Maura Rolle, Gilles Mailhot, Marcello Brigante, Claudio Minero, Davide Vione, Valter Maurino, Babita Sur, Brigante, Marcello, Dipartimento di Chimica IFM and NIS, Università degli studi di Torino = University of Turin (UNITO), Institut de Chimie de Clermont-Ferrand (ICCF), Université Blaise Pascal - Clermont-Ferrand 2 (UBP)-SIGMA Clermont (SIGMA Clermont)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), and Università degli studi di Torino (UNITO)
- Subjects
Ultraviolet Rays ,Radical ,Disproportionation ,Naphthalenes ,010501 environmental sciences ,010402 general chemistry ,Photochemistry ,01 natural sciences ,7. Clean energy ,chemistry.chemical_compound ,Reaction rate constant ,Hydroxides ,Physical and Theoretical Chemistry ,Triplet state ,0105 earth and related environmental sciences ,Photolysis ,Hydroxyl Radical ,Chemistry ,Superoxide ,Photodissociation ,Water ,Hydrogen Peroxide ,Hydrogen-Ion Concentration ,0104 chemical sciences ,[CHIM.THEO]Chemical Sciences/Theoretical and/or physical chemistry ,[CHIM.THEO] Chemical Sciences/Theoretical and/or physical chemistry ,Excited state ,Basic solution ,Quantum Theory ,Oxidation-Reduction - Abstract
The excited triplet state of 1-nitronaphthalene ((3)1NN*) reacts with OH(-) with a second-order reaction rate constant of (1.66 ± 0.08)×10(7) M(-1) s(-1) (μ±σ). The reaction yields the ˙OH radical and the radical anion 1NN(-)˙. In aerated solution, the radical 1NN(-)˙ would react with O(2) to finally produce H(2)O(2) upon hydroperoxide/superoxide disproportionation. The photolysis of H(2)O(2) is another potential source of ˙OH, but such a pathway would be a minor one in circumneutral (pH 6.5) or in basic solution ([OH(-)] = 0.3-0.5 M). The oxidation of H(2)O by (3)1NN*, with rate constant 3.8 ± 0.3 M(-1) s(-1), could be the main ˙OH source at pH 6.5.
- Published
- 2011