TY - JOUR

T1 - Diabatization schemes for generating charge-localized electron-proton vibronic states in proton-coupled electron transfer systems

AU - Sirjoosingh, Andrew

AU - Hammes-Schiffer, Sharon

PY - 2011/9/13

Y1 - 2011/9/13

N2 - A scheme for the rigorous construction of charge-localized diabatic electron-proton vibronic states for proton-coupled electron transfer (PCET) reactions is presented. The diabatic electronic states are calculated using an adiabatic-to-diabatic transformation designed to ensure that the first-order nonadiabatic couplings with respect to a specified one-dimensional reaction coordinate vanish exactly. This scheme is applied to both symmetric and asymmetric PCET systems with several different one-dimensional reaction coordinates, including the hydrogen transfer coordinate, a normal mode coordinate, and the intrinsic reaction coordinate. This approach is also extended to describe the three-dimensional motion of the transferring hydrogen. The diabatic electronic states exhibit relatively invariant charge distributions along the reaction coordinate and are in excellent agreement with the analogous states obtained from the generalized Mulliken-Hush and Boys localization methods. Furthermore, these diabatic electronic states are combined with the associated proton vibrational wave functions to generate charge-localized electron-proton vibronic states that describe one- or three-dimensional hydrogen motion. These electron-proton vibronic states can be used to calculate the vibronic couplings, rate constants, and kinetic isotope effects of PCET reactions.

AB - A scheme for the rigorous construction of charge-localized diabatic electron-proton vibronic states for proton-coupled electron transfer (PCET) reactions is presented. The diabatic electronic states are calculated using an adiabatic-to-diabatic transformation designed to ensure that the first-order nonadiabatic couplings with respect to a specified one-dimensional reaction coordinate vanish exactly. This scheme is applied to both symmetric and asymmetric PCET systems with several different one-dimensional reaction coordinates, including the hydrogen transfer coordinate, a normal mode coordinate, and the intrinsic reaction coordinate. This approach is also extended to describe the three-dimensional motion of the transferring hydrogen. The diabatic electronic states exhibit relatively invariant charge distributions along the reaction coordinate and are in excellent agreement with the analogous states obtained from the generalized Mulliken-Hush and Boys localization methods. Furthermore, these diabatic electronic states are combined with the associated proton vibrational wave functions to generate charge-localized electron-proton vibronic states that describe one- or three-dimensional hydrogen motion. These electron-proton vibronic states can be used to calculate the vibronic couplings, rate constants, and kinetic isotope effects of PCET reactions.

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U2 - 10.1021/ct200356b

DO - 10.1021/ct200356b

M3 - Article

AN - SCOPUS:80052813118

SN - 1549-9618

VL - 7

SP - 2831

EP - 2841

JO - Journal of Chemical Theory and Computation

JF - Journal of Chemical Theory and Computation

IS - 9

ER -