Department of Chemistry and Biochemistry, Queens College of the City University of New York, 65-30 Kissena Boulevard, Flushing, New York 11367, USA.
J Chem Phys. 2012 Jul 14;137(2):024101. doi: 10.1063/1.4732309.
This work extends the theory of coherent resonance energy transfer [S. Jang, J. Chem. Phys. 131, 164101 (2009)] by including quantum mechanical inelastic effects due to modulation of donor-acceptor electronic coupling. Within the approach of the second order time local quantum master equation (QME) in the polaron picture and under the assumption that the bath degrees of freedom modulating the electronic coupling are independent of other modes, a general time evolution equation for the reduced system density operator is derived. Detailed expressions for the relaxation operators and inhomogeneous terms of the QME are then derived for three specific models of modulation in distance, axial angle, and dihedral angle, which are all approximated by harmonic oscillators. Numerical tests are conducted for a set of model parameters. Model calculation shows that the torsional modulation can make significant contribution to the relaxation and dephasing mechanisms.
这项工作通过将由于供体-受体电子耦合的调制而引起的量子力学非弹性效应纳入相干共振能量转移理论[ S. Jang，J. Chem. Phys. 131, 164101 (2009)]。在极化子图像中的二阶时间局部量子主方程（QME）方法内，并且假设调制电子耦合的溶剂自由度与其他模式无关，推导出了简化系统密度算子的一般时间演化方程。然后，针对距离调制、轴向角调制和二面角调制的三个具体模型，推导出了 QME 的弛豫算子和非均匀项的详细表达式，这些模型均通过谐振子进行近似。针对一组模型参数进行了数值测试。模型计算表明，扭转调制可以对弛豫和退相位机制做出重要贡献。
