论文部分内容阅读
电子转移在有机分子及生物体中有重要意义,是目前最活跃的研究领域之一.关于电子转移的速率理论,目前有Marcus的经典模型、对核运动作量子力学处理的量子力学模型,以及忽略核运动隧道效应而考虑非绝热电子态跃迁的半经典模型.在研究对称双势阱结构图1(a)的电子转移时,有适合于弱偶合的半经典动力学模型.而在外电场中,电子转移反应能垒降低,势能面结构不再是对称结构图1(b),这时,基元步骤为放热反应.当外电场达到某一阈值时,反应能垒完全崩溃,变为如图1(c)所示的无能垒结构.在外电场中考察反应的重组能(E_λ),电子转移矩阵元(V_(AB)),活化能及反应速率常数,对分子电子器件等的研究具有重要意义.本文在谐振模型近似下,建议外电场作用下双势阱结构的半经典模型,计算在外电场作用下共线电子转移O_2O_2~-→O_2~-O_2的透热势能面、过渡态结构参数及反应速率常数.
Electron transfer is one of the most active research fields in organic molecules and organisms, and there are currently the classical Marcus model, the quantum mechanics model for nuclear mechanics in quantum mechanics, and the rate theory of electron transfer Ignoring the nuclear motion tunnel effect and taking into account the semi-classical model of non-adiabatic electronic transitions, there is a semi-classical model suitable for weak coupling in the study of the electron transfer of the symmetric double-well structure in Fig. 1 (a) , The energy barrier of the electron transfer reaction is reduced, and the structure of the potential energy surface is no longer symmetrical (Figure 1 (b)). At this time, the elementary step is an exothermic reaction. When the external electric field reaches a certain threshold, the energy barrier completely crushes and becomes The non-barrier structure is shown in Fig.1 (c). The reaction energy (E_λ), electron transfer matrix (V_ (AB)), activation energy and reaction rate constant are investigated in the external electric field Which is of great importance.In this paper, we proposed a semi-classical model of double-well structure under the action of an external electric field under the approximation of the resonant model, and calculated the trans-thermal potential energy surface of the collinear electron transfer O 2 O 2 ~ - → O 2 ~ -O 2 under the external electric field, Structural parameters and inverse Rate constant.