메뉴 건너뛰기




Volumn 108, Issue 52, 2004, Pages 11793-11808

Kinetic isotope effects for nonadiabatic proton transfer reactions in a polar environment 1. Interpretation of tunneling kinetic isotopic effects

Author keywords

[No Author keywords available]

Indexed keywords

ARRHENIUS ACTIVATION ENERGY; KINETIC ISOTOPE EFFECTS (KIE); PROTON TRANSFER (PT); TEMPERATURE DEPENDENCE;

EID: 11344269742     PISSN: 10895639     EISSN: None     Source Type: Journal    
DOI: 10.1021/jp040497p     Document Type: Article
Times cited : (110)

References (110)
  • 4
    • 0000697715 scopus 로고
    • (d) Hibbert, F. Adv. Phys. Org. Chem. 1986, 22, 113. Hibbert, F. Adv. Phys. Org. Chem. 1990, 26, 255.
    • (1986) Adv. Phys. Org. Chem. , vol.22 , pp. 113
    • Hibbert, F.1
  • 5
    • 77956715871 scopus 로고
    • (d) Hibbert, F. Adv. Phys. Org. Chem. 1986, 22, 113. Hibbert, F. Adv. Phys. Org. Chem. 1990, 26, 255.
    • (1990) Adv. Phys. Org. Chem. , vol.26 , pp. 255
    • Hibbert, F.1
  • 31
    • 11344277790 scopus 로고    scopus 로고
    • note
    • 9. 10.
  • 44
    • 0034734365 scopus 로고    scopus 로고
    • For tunneling calculations consistent with the stanadard view, see: (a) Alhambra, C.; Corchado, J. C.; Sánchez, M. L.; Gao, J.; Truhlar, D. G. J. Am. Chem. Soc. 2000, 122, 8197. (b) Hwang, J.-K.; Warshel, A, J. Phys. Chem. 1993, 97, 10053. (c) Hwang, J.-K.; Chu, Z. T.; Yadav, A.; Warshel, A.J. Phys. Chem. 1991, 95, 8445. (d) Hwang, J.-K.; Warshel, A. J. Am. Chem. Soc. 1996, 118, 11745. (e) Alhambra, C.; Gao, J.; Corchado, J. C.; Villa, J.; Truhlar, D. G. J. Am. Chem. Soc. 1999, 121, 2253. (f) Cui, Q.; Karplus, M. J. Am. Chem. Soc. 2002, 124, 3093.
    • (2000) J. Am. Chem. Soc. , vol.122 , pp. 8197
  • 45
    • 33751386561 scopus 로고
    • For tunneling calculations consistent with the stanadard view, see: (a) Alhambra, C.; Corchado, J. C.; Sánchez, M. L.; Gao, J.; Truhlar, D. G. J. Am. Chem. Soc. 2000, 122, 8197. (b) Hwang, J.-K.; Warshel, A, J. Phys. Chem. 1993, 97, 10053. (c) Hwang, J.-K.; Chu, Z. T.; Yadav, A.; Warshel, A.J. Phys. Chem. 1991, 95, 8445. (d) Hwang, J.-K.; Warshel, A. J. Am. Chem. Soc. 1996, 118, 11745. (e) Alhambra, C.; Gao, J.; Corchado, J. C.; Villa, J.; Truhlar, D. G. J. Am. Chem. Soc. 1999, 121, 2253. (f) Cui, Q.; Karplus, M. J. Am. Chem. Soc. 2002, 124, 3093.
    • (1993) J. Phys. Chem. , vol.97 , pp. 10053
    • Hwang, J.-K.1    Warshel, A.2
  • 46
    • 0040193886 scopus 로고
    • For tunneling calculations consistent with the stanadard view, see: (a) Alhambra, C.; Corchado, J. C.; Sánchez, M. L.; Gao, J.; Truhlar, D. G. J. Am. Chem. Soc. 2000, 122, 8197. (b) Hwang, J.-K.; Warshel, A, J. Phys. Chem. 1993, 97, 10053. (c) Hwang, J.-K.; Chu, Z. T.; Yadav, A.; Warshel, A.J. Phys. Chem. 1991, 95, 8445. (d) Hwang, J.-K.; Warshel, A. J. Am. Chem. Soc. 1996, 118, 11745. (e) Alhambra, C.; Gao, J.; Corchado, J. C.; Villa, J.; Truhlar, D. G. J. Am. Chem. Soc. 1999, 121, 2253. (f) Cui, Q.; Karplus, M. J. Am. Chem. Soc. 2002, 124, 3093.
    • (1991) J. Phys. Chem. , vol.95 , pp. 8445
    • Hwang, J.-K.1    Chu, Z.T.2    Yadav, A.3    Warshel, A.4
  • 47
    • 0029951263 scopus 로고    scopus 로고
    • For tunneling calculations consistent with the stanadard view, see: (a) Alhambra, C.; Corchado, J. C.; Sánchez, M. L.; Gao, J.; Truhlar, D. G. J. Am. Chem. Soc. 2000, 122, 8197. (b) Hwang, J.-K.; Warshel, A, J. Phys. Chem. 1993, 97, 10053. (c) Hwang, J.-K.; Chu, Z. T.; Yadav, A.; Warshel, A.J. Phys. Chem. 1991, 95, 8445. (d) Hwang, J.-K.; Warshel, A. J. Am. Chem. Soc. 1996, 118, 11745. (e) Alhambra, C.; Gao, J.; Corchado, J. C.; Villa, J.; Truhlar, D. G. J. Am. Chem. Soc. 1999, 121, 2253. (f) Cui, Q.; Karplus, M. J. Am. Chem. Soc. 2002, 124, 3093.
    • (1996) J. Am. Chem. Soc. , vol.118 , pp. 11745
    • Hwang, J.-K.1    Warshel, A.2
  • 48
    • 0033577302 scopus 로고    scopus 로고
    • For tunneling calculations consistent with the stanadard view, see: (a) Alhambra, C.; Corchado, J. C.; Sánchez, M. L.; Gao, J.; Truhlar, D. G. J. Am. Chem. Soc. 2000, 122, 8197. (b) Hwang, J.-K.; Warshel, A, J. Phys. Chem. 1993, 97, 10053. (c) Hwang, J.-K.; Chu, Z. T.; Yadav, A.; Warshel, A.J. Phys. Chem. 1991, 95, 8445. (d) Hwang, J.-K.; Warshel, A. J. Am. Chem. Soc. 1996, 118, 11745. (e) Alhambra, C.; Gao, J.; Corchado, J. C.; Villa, J.; Truhlar, D. G. J. Am. Chem. Soc. 1999, 121, 2253. (f) Cui, Q.; Karplus, M. J. Am. Chem. Soc. 2002, 124, 3093.
    • (1999) J. Am. Chem. Soc. , vol.121 , pp. 2253
    • Alhambra, C.1    Gao, J.2    Corchado, J.C.3    Villa, J.4    Truhlar, D.G.5
  • 49
    • 0037181354 scopus 로고    scopus 로고
    • For tunneling calculations consistent with the stanadard view, see: (a) Alhambra, C.; Corchado, J. C.; Sánchez, M. L.; Gao, J.; Truhlar, D. G. J. Am. Chem. Soc. 2000, 122, 8197. (b) Hwang, J.-K.; Warshel, A, J. Phys. Chem. 1993, 97, 10053. (c) Hwang, J.-K.; Chu, Z. T.; Yadav, A.; Warshel, A.J. Phys. Chem. 1991, 95, 8445. (d) Hwang, J.-K.; Warshel, A. J. Am. Chem. Soc. 1996, 118, 11745. (e) Alhambra, C.; Gao, J.; Corchado, J. C.; Villa, J.; Truhlar, D. G. J. Am. Chem. Soc. 1999, 121, 2253. (f) Cui, Q.; Karplus, M. J. Am. Chem. Soc. 2002, 124, 3093.
    • (2002) Cui, Q.; Karplus, M. J. Am. Chem. Soc. , vol.124 , pp. 3093
  • 73
    • 11344287396 scopus 로고    scopus 로고
    • note
    • 24 The reorganization energy for proton tunneling is the free energy difference associated with a Franck-Condon-like excitation (all nuclear and solvent modes other than the proton mode are held fixed) of the ground diabatic proton vibrational state at the equilibrium reactant solvent position to the ground product diabatic proton vibrational state, followed by relaxation along the solvent coordinate to the equilibrium solvent product position (see Figure Id).
  • 77
    • 11344288365 scopus 로고    scopus 로고
    • note
    • 23 by the free energy difference associated with a Franck-Condon electronic excitation from the equilibrium reactant solvent position on the reactant electronic diabatic surface to the product electronic diabatic state, followed by relaxation in a solvent coordinate to the equilibrium product position.
  • 78
    • 11344279952 scopus 로고    scopus 로고
    • note
    • 9.10
  • 79
    • 11344279618 scopus 로고    scopus 로고
    • note
    • 27. 28
  • 82
    • 0001954833 scopus 로고
    • Ratajcak, H. Orville-Thomas, W. J., Eds.; John Wiley & Sons; New York
    • (b) Zeegers-Huyskens, T.; Huyskens, P. In Molecular Interactions; Ratajcak, H. Orville-Thomas, W. J., Eds.; John Wiley & Sons; New York, 1980; Vol. 2, p I.
    • (1980) Molecular Interactions , vol.2
    • Zeegers-Huyskens, T.1    Huyskens, P.2
  • 83
    • 11344249200 scopus 로고    scopus 로고
    • note
    • Some PT systems will undoubtedly contain a mixture of nonadiabatic and adiabatic behavior. For example, the proton could be thermally excited where the proton vibrational state is above the barrier in the proton coordinate or it can tunnel through the proton barrier. The rate for the mixed case is the sum of the adiabatic and nonadiabatic PT rates, and the KIEs would thus be a convolution of adiabatic and nonadiabatic PT KIEs. See examples in ref 6.
  • 87
    • 0004016059 scopus 로고
    • Holt, Rinehart, and Winston, Inc.: San Francisco, CA
    • (c) Rapp, D. Quantum Mechanics; Holt, Rinehart, and Winston, Inc.: San Francisco, CA, 1971.
    • (1971) Quantum Mechanics
    • Rapp, D.1
  • 89
    • 11344251498 scopus 로고    scopus 로고
    • note
    • 5d.18 Henceforth, we assume the linear exponential form in eq 2.4.
  • 91
    • 11344259223 scopus 로고    scopus 로고
    • note
    • -1, a value also consistent with the mass dependence.
  • 92
    • 11344273875 scopus 로고    scopus 로고
    • note
    • 30 Here we consider a linear H-bond system, where any bending contributions have been renormalized into the single H-bond mode frequency and separation. For simulation examples where the proton coordinate is treated with a stretch and bend, see ref 6.
  • 93
    • 11344275918 scopus 로고    scopus 로고
    • note
    • 5d, e
  • 94
    • 11344279951 scopus 로고    scopus 로고
    • note
    • 5a
  • 95
    • 11344281656 scopus 로고    scopus 로고
    • note
    • The H-bond vibrational mode is assumed in this paper to remain significantly unchanged while the reaction coordinate fluctuates from the 0-0 TS to either the 0-1 or 1-0 TS.
  • 96
    • 11344281146 scopus 로고    scopus 로고
    • note
    • p) term in eq 2.21 is an estimate for the decrease in barrier height for excited states.
  • 97
    • 11344281971 scopus 로고    scopus 로고
    • note
    • eqL are based on model calculations by the present authors. Furthermore, these approximations are key provisions that allow for the development of the quantitative analysis in section 3, specifically those that indicate explicit contributions from excited proton states. While slight deviations from these approximations are possible and likely for real systems, the quantitative trends that result from the present analysis are not significantly altered by such deviations.
  • 98
    • 11344280870 scopus 로고    scopus 로고
    • note
    • 13,14for nontunneling PT states that for a symmetric reaction the TS mode is purely classical proton motion, so that the TS mode includes more of the donor-acceptor mode as the reaction becomes more a symmetric. Thus, the TS mode mass increases with reaction asymmetry, and tunneling by H (or D) is less with increasing asymmetry, giving a maximal KIE for pure H (or D) motion for symmetric reaction and lower KIEs for less H (or D) tunneling at TS.
  • 99
    • 11344288884 scopus 로고    scopus 로고
    • note
    • 44 demonstrate that an 'inverted' regime is possible for PT, the physical aspects of these systems that allow for observation of an 'inverted' regime remain to be clarified.
  • 104
    • 11344281147 scopus 로고    scopus 로고
    • note
    • RXN = 0.
  • 105
    • 11344277792 scopus 로고    scopus 로고
    • note
    • Of course, in the solution case, the solvent would need to remain liquid and classical. More generally, the environment would have to remain classical.
  • 106
    • 11344268868 scopus 로고    scopus 로고
    • note
    • 34 we have included the T dependence of the dielectric constant ε of water and find (i) a ∼20% reduction of the rale Arrhenius slopes and (ii) only a slight effect (<5%) on the KIE Arrhenius slope.
  • 107
    • 11344287899 scopus 로고    scopus 로고
    • note
    • This is particularly true for H atom transfer reactions because they are weakly coupled to a polar environment, i.e., small reorganization energies (cf. the H atom transfer reaction in ref 5e).
  • 108
    • 11344251496 scopus 로고    scopus 로고
    • note
    • ≠ = 9.25 kcal/mol, the proton or deuteron could be excited to a vibrational state above the proton barrier, and PT would then proceed via a nontunneling process. At this low T, however, the rate constant for such a process is many order of magnitudes smaller (for both H and D) than the tunneling rate constants.
  • 109
    • 11344252250 scopus 로고    scopus 로고
    • note
    • o}. If a PT system was in the nontunneling regime at high temperatures one might expect that lowering the temperature would put the PT system in the tunneling regime, and thus one would expect a large Swain-Schaad ratio at low temperatures that progressively decreases toward the expected value eq 3.19 as T is increased. Figure 12c, however, displays the T dependence for a PT system that remains in the tunneling regime at all the displayed temperatures.
  • 110
    • 11344272105 scopus 로고    scopus 로고
    • note
    • Se where the coupling to the solvent is weak, and e.g., the temperature dependence and KIE magnitude are quite different from those found in the present work.


* 이 정보는 Elsevier사의 SCOPUS DB에서 KISTI가 분석하여 추출한 것입니다.