Dynamical non-Condon effects in resonant tunneling

TL;DR

This paper investigates how dynamical non-Condon effects influence electron transfer rates in resonant tunneling, revealing that these effects can significantly enhance the transfer rate through a combined theoretical and computational approach.

Contribution

The study introduces a generalized time-dependent Fermi's golden rule for ET in the resonant tunneling regime and demonstrates the importance of dynamical non-Condon effects through simulations.

Findings

Dynamical non-Condon effects can significantly enhance ET rates.

The generalized T-matrix framework effectively captures resonance effects.

Computational results support the importance of dynamical contributions in ET.

Abstract

It is well known that the electron transfer (ET) reaction in donor-bridge-acceptor systems is much influenced by the bridge conformational changes. However, the importance of the dynamical contribution to the ET rate is still under debate. In this study, we investigate the significance of the dynamical non-Condon effect on the ET rate in the coherent resonant tunneling regime. To deal with the resonance, we generalize the time-dependent Fermi's golden rule expression for the ET rate in the $T$-matrix framework. The dynamical effect is thereby expressed in terms of the time correlation function of the non-Hermitian $T$-matrix. We discuss the property of the quantum time correlation function of the non-Hermitian $T$-matrix and construct the semiclassical approximation. Then we perform a computational study using classical equilibrium molecular dynamics simulations and quantum chemical calculations. It is shown that the ET rate can be significantly enhanced by the dynamical non-Condon effects.