Path Integral Theory of Electron Transport in Chemical and Biological Systems

麦志豪获得理论与计算化学项目的资助，继续他在化学和生物体系中电子传输的路径积分理论的研究。将Feynman路径积分理论与量子蒙特卡罗方法相结合，研究了多种分子电子系统中的电子输运机制。结合电子转移反应的量子力学特征，考察了化学环境对电子运动的影响。我们将研究隧道效应、相干、量子干涉和电子关联的各个方面，并努力了解绝热和非绝热势垒穿越的交叉区。应用包括研究细菌光合作用反应中心的电荷分离率，一种潜在有用的分子量子干涉装置，以及一维分子线的量子电导。理解电子在分子体系中的长程输运具有重要的理论意义。它也是一个迅速发展的领域的关键目标之一，这个领域已经成为众所周知的分子电子学。分子电子学涉及通过使用外部信号来控制分子中的电子流动。这一领域的工作可能最终导致电子设备在分子维度的数量级上微型化。

Chi Ho Mak is supported by a grant from the Theoretical and Computational Chemistry Program to continue his research in path integral theory of electron transport in chemical and biological systems. Feynman path integral theory is applied in conjunction with Quantum Monte Carlo techniques to the study of the mechanisms for electron transport in a number of molecular electronic systems. The influence of the chemical environment on the motions of the electron is examined in relation to the quantum mechanical features of electron transfer reactions. Various aspects of tunneling, coherence, quantum interference and electron correlation will be studied, and an effort will be made to understand the crossover region between adiabatic and nonadiabatic barrier crossings. Applications include studies of charge separation rate in the bacterial photosynthetic reaction center, a potentially useful molecular quantum interference device, and quantum conductance of one-dimensional molecular wires. The understanding of long-range transport of electrons in molecular systems is of fundamental theoretical importance. It is also one of the key objectives in a rapidly growing area which has become known as molecular electronics. Molecular electronics involves the control of electron flows in molecules through the use of external signals. Work in this area may eventually lead to electronic devices with miniaturization on the order of molecular dimensions.