Collaborative Research: Infra-red Control of Electron Transfer Mechanisms

在这个由化学部化学结构、动力学和机理B项目资助的合作项目中，杜克大学化学系的David N. Beratan教授和Peng Zhang教授以及杜兰大学化学系的Igor V. Rubtsov教授和Russell H. Schmehl教授正在开发控制电荷通过分子流动的新方法。在自然发生的反应和具有技术意义的装置中，分子尺度上的电子转移是必不可少的。调节电子运动速率和在分子尺度上控制这些反应的方向性的能力是一个重大的挑战，它可以为太阳能转换开辟新的策略，为理解生物能量转换方案，以及为具有技术意义的设备开发新的策略。该项目包括化学合成、超快光谱学和理论的紧密合作，为学生建立一个非常丰富的跨学科训练环境。该团队正在通过向经济上处于不利地位和历史上代表性不足的群体提供夏季研究机会来促进科学和教育。此外，新课程的开发涉及多大学、多学院的课程教学，这些课程涉及支撑研究的化学和物理原理。该项目的总体目标是了解在分子尺度上使用红外微扰来控制电荷流动的化学和物理方法。该研究还包括设计新的分子结构，其中电荷流受到红外辐射的强烈影响。该项目结合了理论和实验方法的力量来操纵分子中的电荷流。研究人员在实验室中使用超快多脉冲光谱方法来驱动和干扰供体-桥体-受体化合物的反应动力学。制备和研究了几种给体-桥体-受体分子体系，包括过渡金属配合物、双金属配合物、氢键体系和双稳桥体系。利用新开发的非平衡分子动力学方法，模拟了在实验实验室中检测的相同分子系统，旨在理解可能干扰反应坐标运动和供体-受体电子耦合相互作用的振动激发。

In this collaborative project funded by the Chemical Structure, Dynamics & Mechanisms B Program of the Chemistry Division, Professors David N. Beratan and Peng Zhang of the Department of Chemistry at Duke University and Professors Igor V. Rubtsov and Russell H. Schmehl of the Department of Chemistry at Tulane University are developing novel ways to control the flow of electrical charge through molecules. Electron transfer at the molecular scale is essential in naturally occurring reactions and in devices of technological significance. The ability to dial in the rate of electronic motion and to control the directionality of these reactions on the molecular scale is a significant challenge that could open up new strategies for solar energy conversion, for understanding of biological energy conversion schemes, and for developing new strategies for devices of technological significance. The project includes intensive collaborations among chemical synthesis, ultrafast spectroscopy, and theory to establish a very rich interdisciplinary training environment for students. The team is promoting science and education by providing summer research opportunities to economically-disadvantaged and historically underrepresented groups. In addition, novel curriculum developments involve multi-university, multi-faculty teaching of courses that address the chemical and physical principles underpinning the research. The overall aim of the project is to understand the chemical and physical approaches that use infrared perturbations to control charge flow at the molecular scale. The research also includes the design of novel molecular structures where the charge flow is strongly influenced by the infra-red radiation. The project combines the power of theoretical and experimental approaches to manipulate charge flow in molecules. The researchers use ultrafast multi-pulse spectroscopic methods in the laboratory to drive and to perturb the reaction dynamics of donor-bridge-acceptor compounds. Several classes of donor-bridge-acceptor molecular systems are prepared and studied, including transition-metal complexes, bimetallic complexes, hydrogen-bonded systems, and systems with bi-stable bridges. Using newly developed methods of non-equilibrium molecular dynamics, the same molecular systems examined in the experimental laboratory are simulated, targeting the development of understanding vibrational excitation that may perturb both reaction coordinate motion and donor-acceptor electronic coupling interactions.