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Soc."],"published-print":{"date-parts":[[2009,8,26]]},"DOI":"10.1021\/ja904400d","type":"journal-article","created":{"date-parts":[[2009,7,20]],"date-time":"2009-07-20T13:41:19Z","timestamp":1248097279000},"page":"11985-11997","source":"Crossref","is-referenced-by-count":85,"title":["Nitroxyl Radical Plus Hydroxylamine Pseudo Self-Exchange Reactions: Tunneling in Hydrogen Atom Transfer"],"prefix":"10.1021","volume":"131","author":[{"given":"Adam","family":"Wu","sequence":"first","affiliation":[{"name":"Department of Chemistry, Campus Box 351700, University of Washington, Seattle, Washington 98195-1700, and Department of Chemistry and the Center for Advanced Scientific Computing and Modeling, University of North Texas, 1155 Union Circle, 305070, Denton, Texas 76203-5070"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Elizabeth A.","family":"Mader","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Campus Box 351700, University of Washington, Seattle, Washington 98195-1700, and Department of Chemistry and the Center for Advanced Scientific Computing and Modeling, University of North Texas, 1155 Union Circle, 305070, Denton, Texas 76203-5070"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ayan","family":"Datta","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Campus Box 351700, University of Washington, Seattle, Washington 98195-1700, and Department of Chemistry and the Center for Advanced Scientific Computing and Modeling, University of North Texas, 1155 Union Circle, 305070, Denton, Texas 76203-5070"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"David A.","family":"Hrovat","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Campus Box 351700, University of Washington, Seattle, Washington 98195-1700, and Department of Chemistry and the Center for Advanced Scientific Computing and Modeling, University of North Texas, 1155 Union Circle, 305070, Denton, Texas 76203-5070"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Weston Thatcher","family":"Borden","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Campus Box 351700, University of Washington, Seattle, Washington 98195-1700, and Department of Chemistry and the Center for Advanced Scientific Computing and Modeling, University of North Texas, 1155 Union Circle, 305070, Denton, Texas 76203-5070"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"James M.","family":"Mayer","sequence":"additional","affiliation":[{"name":"Department of Chemistry, Campus Box 351700, University of Washington, Seattle, Washington 98195-1700, and Department of Chemistry and the Center for Advanced Scientific Computing and Modeling, University of North Texas, 1155 Union Circle, 305070, Denton, Texas 76203-5070"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"316","published-online":{"date-parts":[[2009,7,20]]},"reference":[{"key":"ref1\/cit1","volume-title":"Hydrogen-Transfer Reactions","author":"Hynes J. 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K.Determination of Organic Reaction Mechanisms;John Wiley & Sons:New York, 1984; pp83\u2212111."},{"key":"ref5\/cit5a","doi-asserted-by":"crossref","first-page":"1323","DOI":"10.1098\/rstb.2006.1870","volume":"361","author":"Klinman J. P.","year":"2006","journal-title":"Phil. Trans. R. Soc. B"},{"key":"ref5\/cit5b","doi-asserted-by":"crossref","first-page":"1375","DOI":"10.1098\/rstb.2006.1878","volume":"361","author":"Sutcliffe M. J.","year":"2006","journal-title":"Phil. Trans. R. Soc. B"},{"key":"ref5\/cit5c","doi-asserted-by":"crossref","first-page":"254","DOI":"10.1002\/poc.1463","volume":"22","author":"Barroso M.","year":"2009","journal-title":"J. Phys. Org. Chem."},{"key":"ref5\/cit5d","doi-asserted-by":"crossref","first-page":"8140","DOI":"10.1021\/ic020731v","volume":"42","author":"Meyer T. J.","year":"2003","journal-title":"Inorg. Chem."},{"key":"ref5\/cit5e","doi-asserted-by":"crossref","first-page":"6979","DOI":"10.1021\/ja00094a080","volume":"116","author":"Reinaudt O. 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L., Eds.Wiley-VCH:Weinheim, 2007; Volume4, pp1241\u22121284."},{"key":"ref9\/cit9b","doi-asserted-by":"crossref","first-page":"705","DOI":"10.1021\/cr9400875","volume":"98","author":"Stubbe J.","year":"1998","journal-title":"Chem. Rev."},{"key":"ref9\/cit9c","volume-title":"Free Radicals in Biology and Medicine","author":"Halliwell B.","year":"1999"},{"key":"ref10\/cit10a","doi-asserted-by":"crossref","first-page":"3865","DOI":"10.1021\/ja012205t","volume":"124","author":"Knapp M. J.","year":"2002","journal-title":"J. Am. Chem. Soc."},{"key":"ref10\/cit10b","doi-asserted-by":"crossref","first-page":"1395","DOI":"10.1021\/ja983083g","volume":"121","author":"Lewis E. R.","year":"1999","journal-title":"J. Am. Chem. 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Res."},{"key":"ref12\/cit12d","unstructured":"dFor other applications of nitroxyl radicals, see refs 5\u221220 in"},{"key":"ref12\/cit12dd","doi-asserted-by":"crossref","first-page":"2322","DOI":"10.1021\/ic062010s","volume":"46","author":"Vasbinder M. J.","year":"2007","journal-title":"Inorg. Chem."},{"key":"ref13\/cit13a","doi-asserted-by":"crossref","first-page":"2645","DOI":"10.1021\/ja00964a004","volume":"88","author":"Kreilick R. W.","year":"1966","journal-title":"J. Am. Chem. Soc."},{"key":"ref13\/cit13b","doi-asserted-by":"crossref","first-page":"1654","DOI":"10.1021\/ja01008a047","volume":"90","author":"Arick M. R.","year":"1968","journal-title":"J. Am. Chem. Soc."},{"key":"ref14\/cit14a","doi-asserted-by":"crossref","first-page":"472","DOI":"10.1007\/s10975-005-0100-1","volume":"46","author":"Malievskii A. D.","year":"2005","journal-title":"Kinet. 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Chem."},{"key":"ref17\/cit17b","doi-asserted-by":"crossref","first-page":"4262","DOI":"10.1021\/jp0276193","volume":"107","author":"Koshino N.","year":"2003","journal-title":"J. Phys. Chem. A."},{"key":"ref17\/cit17c","doi-asserted-by":"crossref","first-page":"1747","DOI":"10.1021\/jo026660z","volume":"68","author":"Amorati R.","year":"2003","journal-title":"J. Org. Chem."},{"key":"ref18\/cit18","doi-asserted-by":"crossref","first-page":"238","DOI":"10.1021\/jo048418t","volume":"70","author":"Cai Y.","year":"2005","journal-title":"J. Org. Chem."},{"key":"ref19\/cit19","doi-asserted-by":"crossref","first-page":"2524","DOI":"10.1126\/science.1066130","volume":"294","author":"Roth J. P.","year":"2001","journal-title":"Science"},{"key":"ref20\/cit20","doi-asserted-by":"crossref","first-page":"8066","DOI":"10.1021\/ja049246k","volume":"126","author":"Mader E. A.","year":"2004","journal-title":"J. Am. Chem. Soc."},{"key":"ref21\/cit21","unstructured":"Warren, J. J. and Mayer, J. M.manuscript in preparation."},{"key":"ref22\/cit22","unstructured":"HAT rate constants have traditionally been analyzed using a correlation of Arrhenius activation energy\n                      E\n                      a\n                      with enthalpic driving force \u0394\n                      H\n                      (the Bell-Evans-Polanyi relation), together with \u201cpolar effects\u201d and other influences."},{"key":"ref22\/cit22a","unstructured":"aIngold, K. U.InFree Radicals;Kochi, J. K., Ed.Wiley:New York, 1973; Volume 1, p69ff."},{"key":"ref22\/cit22b","unstructured":"bRussel, G. A.InFree Radicals;Kochi, J. K., Ed.Wiley:New York, 1973; Volume 1, pp275\u2212331."},{"key":"ref22\/cit22c","unstructured":"cO\u2019Neal, H. E. and Benson, S. W.InFree Radicals;Kochi, J. K., Ed.Wiley:New York, 1973; Volume 2, p302ff."},{"key":"ref22\/cit22d","doi-asserted-by":"crossref","first-page":"401","DOI":"10.1002\/anie.198204011","volume":"21","author":"Tedder J. M.","year":"1982","journal-title":"Angew. Chem., Int. Ed. Engl."},{"key":"ref23\/cit23a","doi-asserted-by":"crossref","first-page":"5153","DOI":"10.1021\/ja0686918","volume":"129","author":"Mader E. A.","year":"2007","journal-title":"J. Am. Chem. Soc."},{"key":"ref23\/cit23b","doi-asserted-by":"crossref","first-page":"4335","DOI":"10.1021\/ja8081846","volume":"131","author":"Mader E. A.","year":"2009","journal-title":"J. Am. Chem. Soc."},{"key":"ref24\/cit24","unstructured":"acac = 2,4-pentanedionato; py-imH = 2-(2\u2032-pyridyl)imidazole."},{"key":"ref24\/cit24a","doi-asserted-by":"crossref","first-page":"11190","DOI":"10.1021\/ic7015726","volume":"46","author":"Wu A.","year":"2007","journal-title":"Inorg. Chem."},{"key":"ref24\/cit24b","doi-asserted-by":"crossref","first-page":"14745","DOI":"10.1021\/ja805067h","volume":"130","author":"Wu A.","year":"2008","journal-title":"J. Am. Chem. Soc."},{"key":"ref25\/cit25","volume-title":"NUTS - NMR Utility Transform Software","year":"2003","edition":"1"},{"key":"ref26\/cit26","doi-asserted-by":"crossref","first-page":"10819","DOI":"10.1021\/ja961469q","volume":"118","author":"Bordwell F. G.","year":"1996","journal-title":"J. Am. Chem. Soc."},{"key":"ref27\/cit27a","unstructured":"Mader, E. A.,unpublished results."},{"key":"ref28\/cit28","volume-title":"SPECFIT\/32","year":"2000","edition":"3"},{"key":"ref29\/cit29","unstructured":"The \u201ctrue\u201d\n                      k\n                      H\n                      \/\n                      k\n                      D\n                      , at complete deuteration, is equal to \u03c7(D)\/[(\n                      k\n                      H\n                      \/\n                      k\n                      D\n                      )\n                      obs\n                      \u22121\n                      \u2212 \u03c7(H)], where \u03c7(H) and \u03c7(D) are the mole-fraction in H and D, respectively. For a discussion of the residual protio effect on the observed\n                      k\n                      H\n                      \/\n                      k\n                      D\n                      , see:"},{"key":"ref29\/cit29a","doi-asserted-by":"crossref","first-page":"7293","DOI":"10.1021\/ja00069a031","volume":"115","author":"Sorokin A.","year":"1993","journal-title":"J. Am. Chem. Soc."},{"key":"ref31\/cit31","volume-title":"GAUSSRATE","author":"Corchado J. C.","year":"2007","edition":"9"},{"key":"ref32\/cit32","volume-title":"Gaussian 03","author":"Frisch M. J.","year":"2004","edition":"02"},{"key":"ref33\/cit33","volume-title":"POLYRATE","author":"Corchado J. C.","year":"2007","edition":"9"},{"key":"ref34\/cit34","doi-asserted-by":"crossref","first-page":"4811","DOI":"10.1021\/jp000497z","volume":"104","author":"Lynch B. J.","year":"2000","journal-title":"J. Phys. Chem. A"},{"key":"ref35\/cit35","doi-asserted-by":"crossref","first-page":"364","DOI":"10.1021\/ct0502763","volume":"2","author":"Zhao Y.","year":"2006","journal-title":"J. Chem. Theory Comput."},{"key":"ref36\/cit36","doi-asserted-by":"crossref","first-page":"215","DOI":"10.1007\/s00214-007-0310-x","volume":"120","author":"Zhao Y.","year":"2008","journal-title":"Theor. Chem. Acc."},{"key":"ref37\/cit37a","doi-asserted-by":"crossref","first-page":"3265","DOI":"10.1063\/1.447079","volume":"80","author":"Frisch M. J.","year":"1984","journal-title":"J. Chem. Phys."},{"key":"ref37\/cit37b","doi-asserted-by":"crossref","first-page":"294","DOI":"10.1002\/jcc.540040303","volume":"4","author":"Clark T.","year":"1983","journal-title":"J. Comput. Chem."},{"key":"ref37\/cit37c","doi-asserted-by":"crossref","first-page":"2257","DOI":"10.1063\/1.1677527","volume":"56","author":"Hehre W. J.","year":"1972","journal-title":"J. Chem. Phys."},{"key":"ref38\/cit38","doi-asserted-by":"crossref","unstructured":"Fernandez-Ramos, A., Ellingson, B. A., Garrett, B. C., and Truhlar, D. G.InReviews in Computational Chemistry, Vol.23;Lipkowitz, K. B. and Cundari, T. R., Eds.Wiley-VCH:Hoboken, NJ, 2007; pp125\u2212232.","DOI":"10.1002\/9780470116449.ch3"},{"key":"ref39\/cit39","unstructured":"When the tunneling distance is large, there is a temperature range in which D tunnels considerably closer to the top of the barrier than H, so that the probability of passing through or over the barrier is actually greater for D than for H. As a result, in this temperature range,\n                      E\n                      a,D\n                      \u2009\u2212\u2009\n                      E\n                      a,H\n                      > 1.3 kcal\/mol, but log(\n                      A\n                      H\n                      \/\n                      A\n                      D\n                      ) < 0. See, for example,"},{"key":"ref39\/cit39a","doi-asserted-by":"crossref","first-page":"164","DOI":"10.1021\/ja0664279","volume":"129","author":"Shelton G. R.","year":"2007","journal-title":"J. Am. Chem. Soc."},{"key":"ref40\/cit40","unstructured":"In some circumstances, it is valuable to distinguish between an \u201cHAT mechanism,\u201d where the\n                      e\n                      \u2212\n                      and H\n                      +\n                      come from the same AO, and transfer to the same AO, vs a \u201cPCET mechanism,\u201d in which the two particles are transferred between different sets of AOs in the transition structure."},{"key":"ref40\/cit40a","doi-asserted-by":"crossref","first-page":"11142","DOI":"10.1021\/ja012732c","volume":"124","author":"Mayer J. M.","year":"2002","journal-title":"J. Am. Chem. Soc."},{"key":"ref40\/cit40b","doi-asserted-by":"crossref","first-page":"222","DOI":"10.1021\/ar0682029","volume":"40","author":"Litwinienko G.","year":"2007","journal-title":"Acc. Chem. Res."},{"key":"ref40\/cit40c","unstructured":"c"},{"key":"ref40\/cit40cc","doi-asserted-by":"crossref","first-page":"4729","DOI":"10.1021\/ja808698x","volume":"131","author":"Waidmann C. R.","year":"2009","journal-title":"J. Am. Chem. Soc."},{"key":"ref41\/cit41","doi-asserted-by":"crossref","first-page":"5486","DOI":"10.1021\/ja9941328","volume":"122","author":"Roth J. P.","year":"2000","journal-title":"J. Am. Chem. Soc."},{"key":"ref42\/cit42a","unstructured":"a\u0394\n                      G\n                      \u00b0(ET)\u2009=\u2009\u221223.1[\n                      E\n                      (TEMPO\n                      \u2022\n                      )\u2009\u2212\u2009\n                      E\n                      (TEMPO-H)] \u2248 60 kcal mol\n                      \u22121\n                      . \u0394\n                      G\n                      \u00b0(PT)\u2009=\u2009\u22121.37[p\n                      K\n                      a\n                      (TEMPO-H\n                      \u2022+\n                      )\u2009\u2212\u2009p\n                      K\n                      a\n                      (TEMPO-H)]\u2009=\u2009\u0394\n                      G\n                      \u00b0(ET)."},{"key":"ref42\/cit42b","doi-asserted-by":"crossref","first-page":"4896","DOI":"10.1021\/jp0007437","volume":"104","author":"Mori Y.","year":"2000","journal-title":"J. Phys. Chem. A"},{"key":"ref42\/cit42c","doi-asserted-by":"crossref","first-page":"4492","DOI":"10.1021\/ja00351a070","volume":"105","author":"Semmelhack M. F.","year":"1983","journal-title":"J. Am. Chem. Soc."},{"key":"ref42\/cit42d","unstructured":"dp\n                      K\n                      a\n                      (TEMPO-H) \u2248 41 in MeCN is estimated from p\n                      K\n                      a\n                      (TEMPO-H) = 31.0 in DMSO.(26)"},{"key":"ref42\/cit42e","unstructured":"ep\n                      K\n                      a\n                      conversion from DMSO to MeCN:"},{"key":"ref42\/cit42ee","doi-asserted-by":"crossref","first-page":"1306","DOI":"10.1021\/j100553a009","volume":"80","author":"Chantooni M. K.","year":"1976","journal-title":"J. Phys. Chem."},{"key":"ref42\/cit42f","unstructured":"fp\n                      K\n                      a\n                      (TEMPO-H\n                      \u2022+\n                      ) = p\n                      K\n                      a\n                      (TEMPO-H) + 23.1[\n                      E\n                      (TEMPO\n                      \u2022\n                      )\u2009\u2212\u2009\n                      E\n                      (TEMPO-H)]\/1.37\u2009\u2248\u2009\u22123."},{"key":"ref43\/cit43a","doi-asserted-by":"crossref","first-page":"2929","DOI":"10.1021\/ja00115a029","volume":"117","author":"Avila D. V.","year":"1995","journal-title":"J. Am. Chem. Soc."},{"key":"ref43\/cit43b","doi-asserted-by":"crossref","first-page":"9966","DOI":"10.1021\/ja00145a005","volume":"117","author":"Valgimigli L.","year":"1995","journal-title":"J. Am. Chem. Soc."},{"key":"ref43\/cit43c","doi-asserted-by":"crossref","first-page":"469","DOI":"10.1021\/ja002301e","volume":"123","author":"Snelgrove D. W.","year":"2001","journal-title":"J. Am. Chem. Soc."},{"key":"ref44\/cit44a","unstructured":"aIn the Litwinienko\/Ingold\/Abraham model,(43, 44b, 44c)the CH\n                      2\n                      Cl\n                      2\n                      \/MeCN kinetic solvent effect is given by log(\n                      k\n                      CH2Cl2\n                      \/\n                      k\n                      MeCN\n                      ) = 8.3\u03b1\n                      2\n                      H\n                      (\u03b2\n                      2\n                      H\n                      MeCN\n                      \u2212 \u03b2\n                      2\n                      H\n                      CH2Cl2\n                      ). Using \u03b1\n                      2\n                      H\n                      (the solute constant) = 0.29 for dialkylhydroxylamines and \u03b2\n                      2\n                      H\n                      (the hydrogen-bond acceptor solvent constant) = 0.44 for MeCN and 0.05 for CH\n                      2\n                      Cl\n                      2\n                      ,(45)this model predicts\n                      k\n                      CH2Cl2\n                      \/\n                      k\n                      MeCN\n                      = 8.7, in modest agreement with the experimental values of 4.8 \u00b1 0.6 and 2.4 \u00b1 0.3 for reactions 2 and 4. However, in our experience(44d)this model is not very accurate for reactions in CH\n                      2\n                      Cl\n                      2\n                      (see ref45). The Ingold\/Abraham model may be incomplete for this example because the interaction of TEMPO (\u03b2\n                      2\n                      H\n                      = 0.46) with CH\n                      2\n                      Cl\n                      2\n                      (\u03b1\n                      2\n                      H\n                      = 0.15) may be as important as the interaction of TEMPOH with CH\n                      2\n                      Cl\n                      2\n                      . The radical-solvent interaction is absent in many radical reactions because \u03b1\n                      2\n                      H\n                      (solvent) or \u03b2\n                      2\n                      H\n                      (RO\n                      \u2022\n                      ) is negligible."},{"key":"ref44\/cit44b","doi-asserted-by":"crossref","first-page":"521","DOI":"10.1039\/p29900000521","author":"Abraham M. H.","year":"1990","journal-title":"J. Chem. Soc., Perkin Trans. 2"},{"key":"ref44\/cit44c","doi-asserted-by":"crossref","first-page":"699","DOI":"10.1039\/p29890000699","author":"Abraham M. H.","year":"1989","journal-title":"J. Chem. Soc., Perkin Trans. 2"},{"key":"ref44\/cit44d","unstructured":"dWarren, J. J.,unpublished results."},{"key":"ref45\/cit45a","unstructured":"aThe \u03b2\n                      2\n                      H\n                      is given as 0.05 for CH\n                      2\n                      Cl\n                      2\n                      by Abraham et al.(44b)\n                      ,\n                      (44c)A different value of 0.15 has been suggested using the KSE model,(45b)which was later revised to 0.20.(45c)As pointed out by a reviewer, the agreement with the KSE model is better using these revised values. However, we feel that the KSE model becomes less compelling when the \u03b2\n                      2\n                      H\n                      values are not independent parameters but rather extracted from the radical reaction rates."},{"key":"ref45\/cit45b","doi-asserted-by":"crossref","first-page":"9280","DOI":"10.1021\/ja071716y","volume":"129","author":"Galian R. E.","year":"2007","journal-title":"J. Am. Chem. Soc."},{"key":"ref45\/cit45c","doi-asserted-by":"crossref","first-page":"9270","DOI":"10.1021\/jo8016555","volume":"73","author":"Foti M. C.","year":"2008","journal-title":"J. Org. Chem."},{"key":"ref46\/cit46a","doi-asserted-by":"crossref","first-page":"4395","DOI":"10.1021\/ja00431a010","volume":"98","author":"Knauer B. R.","year":"1976","journal-title":"J. Am. Chem. Soc."},{"key":"ref46\/cit46b","doi-asserted-by":"crossref","first-page":"1231","DOI":"10.1021\/cr960085f","volume":"104","author":"Improta R.","year":"2004","journal-title":"Chem. Rev."},{"key":"ref47\/cit47","doi-asserted-by":"crossref","first-page":"4983","DOI":"10.1021\/ja00039a005","volume":"114","author":"Beckwith A. L. J.","year":"1992","journal-title":"J. Am. Chem. Soc."},{"key":"ref48\/cit48","unstructured":"The experimental difference in zero-point energies for TEMPO-H(D) in MeCN is estimated as 0.5[\n                      \u03bd\n                      OH\n                      \u2009\u2212\u2009\n                      \u03bd\n                      OD\n                      ] = 452 cm\n                      \u22121\n                      = 1.3 kcal mol\n                      \u22121\n                      ."},{"key":"ref49\/cit49","unstructured":"The KIEs are not sensitive to solvent even though the characteristic solvent reorganization times are about a factor of two longer for CH\n                      2\n                      Cl\n                      2\n                      than for MeCN:"},{"key":"ref49\/cit49a","doi-asserted-by":"crossref","first-page":"17311","DOI":"10.1021\/j100048a004","volume":"99","author":"Horng M. L.","year":"1995","journal-title":"J. Phys. Chem."},{"key":"ref50\/cit50a","unstructured":"a\u2009\n                      \n                        t\n                      \n                      Bu\n                      2\n                      NO\n                      \u2022\n                      is slightly more crowded than the cyclic analogs, as reflected in its slightly larger CNC angle of 129.6(3)\u00b0 versus 123.5(2)\u00b0 for 4-oxo-TEMPO\n                      \u2022\n                      ."},{"key":"ref50\/cit50aa","doi-asserted-by":"crossref","first-page":"2667","DOI":"10.1021\/ic00137a027","volume":"21","author":"Cotton F. A.","year":"1982","journal-title":"Inorg. Chem."},{"key":"ref50\/cit50b","doi-asserted-by":"crossref","first-page":"2728.","DOI":"10.3891\/acta.chem.scand.20-2728","volume":"20","author":"Andersen B.","year":"1966","journal-title":"Acta Chem. Scand."},{"key":"ref50\/cit50c","doi-asserted-by":"crossref","first-page":"790","DOI":"10.1107\/S0567740874003712","volume":"30","author":"Bordeaux P. D.","year":"1974","journal-title":"Acta Crystallogr., Sect. B"},{"key":"ref51\/cit51a","unstructured":"a\u2009\n                      E\n                      aD\n                      \u2009\u2212\n                      E\n                      aH\n                      \u2009=\u2009\u22122.8 kcal mol\n                      \u22121\n                      and log(\n                      A\n                      H\n                      \/\n                      A\n                      D\n                      ) = 2.2 have been reported for\n                      e\n                      \u2212\n                      \/H\n                      +\n                      from 2,3-dimethoxy-5-methyl-1,4-benzoquinol to the excited state of [Ru(2,2\u2032-bipyridine)\n                      2\n                      {2-(2-pyridyl)benzimidazolate}\n                      +\n                      ]:"},{"key":"ref51\/cit51aa","doi-asserted-by":"crossref","first-page":"4208","DOI":"10.1021\/ja043955g","volume":"127","author":"Cape J. L.","year":"2005","journal-title":"J. Am. Chem. Soc."},{"key":"ref51\/cit51b","unstructured":"bThis result has very recently been rationalized in terms of being close to the Marcus inverted region for PCET:"},{"key":"ref51\/cit51bb","doi-asserted-by":"crossref","first-page":"7094","DOI":"10.1021\/ja9001184","volume":"131","author":"Ludlow M. K.","year":"2009","journal-title":"J. Am. Chem. Soc."},{"key":"ref51\/cit51c","unstructured":"cHAT self-exchange between [Fe\n                      II\n                      (H\n                      2\n                      bip)\n                      3\n                      ]\n                      2+\n                      and [Fe\n                      III\n                      (H\n                      2\n                      bip)\n                      2\n                      (Hbip)]\n                      2+\n                      (H\n                      2\n                      bip = 2,2\u2032-bi-1,4,5,6-tetrahydropyrimidine) also appears to have negative\n                      E\n                      aD\n                      \u2009\u2212\u2009\n                      E\n                      aH\n                      \u2009=\u2009\u22121.2\u2009\u00b1\u20090.8 kcal mol\n                      \u22121\n                      and positive log(\n                      A\n                      H\n                      \/\n                      A\n                      D\n                      ) = 0.9 \u00b1 1.2 values:"},{"key":"ref51\/cit51cc","doi-asserted-by":"crossref","first-page":"2629","DOI":"10.1021\/ja0273905","volume":"125","author":"Yoder J. C.","year":"2003","journal-title":"J. Am. Chem. Soc."},{"key":"ref52\/cit52","doi-asserted-by":"crossref","first-page":"9440","DOI":"10.1021\/ja00100a005","volume":"116","author":"Foti M.","year":"1994","journal-title":"J. Am. Chem. Soc."},{"key":"ref53\/cit53","doi-asserted-by":"crossref","first-page":"627","DOI":"10.1021\/ja00783a075","volume":"95","author":"Mendenhall G. D.","year":"1973","journal-title":"J. Am. Chem. Soc."},{"key":"ref54\/cit54","doi-asserted-by":"crossref","first-page":"623","DOI":"10.1139\/v75-088","volume":"53","author":"Chenier J. H. B.","year":"1975","journal-title":"Can. J. Chem."},{"key":"ref55\/cit55","doi-asserted-by":"crossref","first-page":"630","DOI":"10.1021\/ja00809a076","volume":"96","author":"Griller D.","year":"1974","journal-title":"J. Am. Chem. Soc."},{"key":"ref56\/cit56","doi-asserted-by":"crossref","first-page":"1736","DOI":"10.1021\/ja00005a042","volume":"113","author":"Bordwell F. G.","year":"1991","journal-title":"J. Am. Chem. Soc."},{"key":"ref57\/cit57a","doi-asserted-by":"crossref","first-page":"3958","DOI":"10.1021\/ja00326a012","volume":"106","author":"Doba T.","year":"1984","journal-title":"J. Am. Chem. Soc."},{"key":"ref57\/cit57b","doi-asserted-by":"crossref","first-page":"3094","DOI":"10.1021\/ja00401a030","volume":"103","author":"Malatesta V.","year":"1981","journal-title":"J. Am. Chem. Soc."},{"key":"ref58\/cit58","doi-asserted-by":"crossref","first-page":"1407","DOI":"10.1002\/hlca.19800630609","volume":"63","author":"Ozinskas A. J.","year":"1980","journal-title":"Helv. Chim. Acta"},{"key":"ref59\/cit59","unstructured":"KaleidaGraph\n                      , version3.5;Synergy SoftwareReading, PA, 2000."}],"container-title":["Journal of the American Chemical Society"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/pubs.acs.org\/doi\/pdf\/10.1021\/ja904400d","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2023,3,15]],"date-time":"2023-03-15T19:52:31Z","timestamp":1678909951000},"score":1,"resource":{"primary":{"URL":"https:\/\/pubs.acs.org\/doi\/10.1021\/ja904400d"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,7,20]]},"references-count":124,"journal-issue":{"issue":"33","published-print":{"date-parts":[[2009,8,26]]}},"alternative-id":["10.1021\/ja904400d"],"URL":"https:\/\/doi.org\/10.1021\/ja904400d","relation":{},"ISSN":["0002-7863","1520-5126"],"issn-type":[{"value":"0002-7863","type":"print"},{"value":"1520-5126","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,7,20]]}}}