TY - JOUR
T1 - Electron transfer rates in bridged molecular systems
T2 - A phenomenological approach to relaxation
AU - Davis, William B.
AU - Wasielewski, Michael R.
AU - Ratner, Mark A.
AU - Mujica, Vladimiro
AU - Nitzan, Abraham
PY - 1997/8/28
Y1 - 1997/8/28
N2 - A model for bridge-assisted, long-range electron transfer in a molecule interacting with a dissipative external bath is presented. The effects of the system-bath interaction are included phenomenologically in the evolution of the system density matrix as energy dephasings on the bridge sites. When the bridge dephasings are small, the steady state ET rate in this model is found to be the sum of two competing terms; the first is a McConnell-type rate arising from direct tunneling from donor to acceptor, and the second is a dephasing-dependent, length-independent scattering channel through the bridge sites. In the limit of large dephasings, an incoherent channel dominates the dynamics and leads to ET rates that can become only weakly dependent (kET ∝ 1/N) on the number of bridge sites in the system, for multisite bridges.
AB - A model for bridge-assisted, long-range electron transfer in a molecule interacting with a dissipative external bath is presented. The effects of the system-bath interaction are included phenomenologically in the evolution of the system density matrix as energy dephasings on the bridge sites. When the bridge dephasings are small, the steady state ET rate in this model is found to be the sum of two competing terms; the first is a McConnell-type rate arising from direct tunneling from donor to acceptor, and the second is a dephasing-dependent, length-independent scattering channel through the bridge sites. In the limit of large dephasings, an incoherent channel dominates the dynamics and leads to ET rates that can become only weakly dependent (kET ∝ 1/N) on the number of bridge sites in the system, for multisite bridges.
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U2 - 10.1021/jp970909c
DO - 10.1021/jp970909c
M3 - Article
AN - SCOPUS:0031209440
SN - 1089-5639
VL - 101
SP - 6158
EP - 6164
JO - Journal of Physical Chemistry A
JF - Journal of Physical Chemistry A
IS - 35
ER -