ABSTRACT
I. Introduction ...................................................................................................................... 549
II. Adiabatic Proton Transfer................................................................................................ 553
A. Adiabatic Proton-Transfer Free-Energy Relationship............................................. 553
1. General Adiabatic Proton-Transfer Picture ...................................................... 553
2. Adiabatic Proton-Transfer Free-Energy Relationship ...................................... 555
3. Further Analysis of the Intrinsic Barrier. Mass Scaling................................... 557
B. Adiabatic Proton-Transfer KIEs .............................................................................. 558
1. KIE Arrhenius Behavior ................................................................................... 559
2. KIE Magnitude and Variation with Reaction Asymmetry............................... 559
3. Swain-Schaad Relationship ............................................................................. 560
C. Further Discussion of Nontunneling KIEs .............................................................. 561
III. Nonadiabatic ‘Tunneling’ Proton Transfer...................................................................... 562
A. General Nonadiabatic Proton-Transfer Perspective and Rate Constant ................. 562
B. Nonadiabatic Proton-Transfer KIEs ........................................................................ 567
1. KIE Magnitude and Variation with Reaction Asymmetry............................... 567
2. Temperature Behavior....................................................................................... 568
3. Swain-Schaad Relationship ............................................................................. 571
IV. Concluding Remarks........................................................................................................ 572
Acknowledgments ........................................................................................................................ 573
References..................................................................................................................................... 573
In this contribution, we give an overview of some of the theoretical developments for primary
kinetic isotope effects (KIEs) for proton-transfer (PT) reactions, primarily focusing on the efforts in
the Hynes group.
