Influence of bridge‐state energy on the electron transfer relaxation and dephasing rate in a donor‐bridge‐acceptor system

Abstract

AbstractThe influence of the bridge‐state energy on the relaxation and dephasing rate of electron transfer in a donor‐bridge‐acceptor system coupling with an open dissipative environment is thoroughly discussed through the QAPUI (quasi‐adiabatic propagator path integral) method in this paper. By calculating the decay rates of the system from the population difference with time between the donor and acceptor with different bridge‐state energy, it is found that the relaxation rate of the system increases with the decreasing of the bridge energy, while the dephasing rate declines in the meantime, when the system‐bath coupling and environment temperature are kept unchanged. The variation trend of both relaxation rate and dephasing rate is consistent with the calculated results of the effective two‐state system, indicating that small reduction in energies of the bridge‐state does not affect the superexchange mechanism of the multiple bridged system. When the energies of the bridge‐state are reduced to cause the bridge population up to 20%, the superexchange mechanism still works quite well in our considered scenarios.