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P.The Tunnel Effect in Chemistry;Chapman & Hall:London, 1980; pp77\u2212101.","DOI":"10.1007\/978-1-4899-2891-7_4"},{"key":"ref44\/cit44","doi-asserted-by":"crossref","first-page":"7116","DOI":"10.1021\/ja00044a024","volume":"114","author":"Kim Y.","year":"1992","journal-title":"J. Am. Chem. Soc."},{"key":"ref45\/cit45","unstructured":"Details are given inSupporting Information."},{"key":"ref46\/cit46","doi-asserted-by":"crossref","first-page":"317","DOI":"10.1016\/j.freeradbiomed.2004.09.037","volume":"38","author":"Israeli A.","year":"2005","journal-title":"Free Radical Biol. Med."},{"key":"ref47\/cit47","unstructured":"Certainly, a fast protonation of TEMPOH takes place subsequently, after the formation of TEMPOH in reaction 1, i.e., this protonation is not a part of the reaction coordinate for the concerted proton and electron transfer in the reaction. It can be seen, among others, that if TEMPOH(H)+would be a \u201cproduct\u201d in reaction 1, then H+must be a \u201creactant\u201d and the rate of reaction should not depend on the reciprocal of H+concentration. Furthermore, if this would be the case, the observed rate constant should be independent on H+; in contrast, the linear dependence on the 1\/H+is what indeed has been observed. The only consequence of that subsequent protonation of TEMPOH is that the concentration of ascorbate in our buffered reaction mixture is more close to a \u201cconstant\u201d during the kinetics since TEMPOH consumed a proton liberated in the dissociation of ascorbic acid (ascorbic acid is in excess, see Experimental section) in the buffer system."},{"key":"ref48\/cit48","doi-asserted-by":"crossref","first-page":"3516","DOI":"10.1021\/ja00402a042","volume":"103","author":"Bielski B. H. J.","year":"1981","journal-title":"J. Am. Chem. 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