【作者】 韩平；

【导师】 何国钟； 严以京；

【作者基本信息】 中国科学院研究生院（大连化学物理研究所） ， 物理化学， 2006， 博士

【摘要】 本文围绕凝聚相中电荷转移的动力学过程中溶液环境对电荷转移过程的影响展开一些研究工作。内容包括发展Debye溶液中电子转移的动力学和热力学的精确解析理论和生物大分子DNA内的长程电荷转移的动力学机理的研究两部分。论文的第一部分我们建立了非微扰的电子反应速率常数的精确解析理论。以往的化学反应速率理论都是建立在微扰理论基础之上的。我们发展的建立在密度矩阵动力学基础之上的非微扰电子反应速率理论不但将同时再现了Kramers’inversion和Marcus’turnover,而且对反应体系的热力学特性给出微观描述,并发现了电子转移体系的一些新的热力学特性。论文的第二部分是电荷在液相DNA中的转移机理研究。目前人们对复杂的DNA中电荷转移过程中所涉及的基本过程似乎认识比较统一,即短的电荷转移过程通过相干隧穿完成,而电荷的长程转移则通过跳跃机理来进行。所有这些短程的或长程的转移过程都是在DNA糖链骨架的振动、溶剂环境极化、极化子的形成等过程的控制下完成的。本文对DNA中电荷转移的部分非相干理论描述合理地包括了对一步相干隧穿(single step tunneling)和连续的多步相干隧穿跳跃(coherent tunneling mediated multistep hopping)这些电荷转移的基本过程的描述。通过与相关实验结果的对比研究,我们澄清了电荷转移各基本机理的适用条件,从而进一步证实部分相干理论能够给出一些电荷在DNA中转移过程的合理图像。更多还原

【Abstract】 The thesis focuses on the effects of solvents on the charge transfer process. It consists of two parts that treat respectively two aspects of charge transfer mechanism: (i) the kinetics and thermodynamics of electron transfer in Debye solvents (ii) the research on long-range charge transfers in DNA. In the first part of the thesis we set up an exact analytical and nonperturbative rate theory based on the reduced density matrix dynamics. We construct an exact analytical and nonperturbative rate theory via dissipation theory approach. Not only has it recover for the reaction rates the celebrated Marcus’inversion and Kramers turnover behaviors, the new theory also predicts for the thermodynamics of reaction some novel turnover features. In part two of the thesis we make an investigation on the mechanism of charge transfer in aqueous DNA. The partially coherent theory adopted to describe the charge transfer process in DNA in this thesis is reasonable including both the description of coherent tunneling and coherent tunneling mediated hopping processes so it can give some reasonable pictures on the real charge transfer process. We make a comparison study between the numerical results of partially coherent theory and experimental results. We make it clear that on what kinds of condition should a mechanism be employed to explain the charge transfer process in DNA.更多还原