The Fundamental Dynamics and Optical Control of Molecular Devices

有了这个奖项，化学系的化学结构、动力学和机制（CSDM-A）项目资助密歇根大学安娜堡分校的Sension教授研究光控纳米机器的分子基组件。这些装置旨在为纳米级遥控传感、传输、合成、记忆、逻辑电路和信息存储提供一种手段。由于对所涉及的复杂系统的不完全了解，这些设备的实际开发在设计上面临着重大挑战。Sension教授将使用超快光谱学来研究与基于光化学开环反应的分子开关、基于中心键周围异构化的分子马达以及能够光激活药物传递的维生素B12类似物相关的分子过程的基本化学和物理。还将开发利用激光脉冲的波长、能量、相位、光束轮廓、偏振和时间结构来智能地操纵潜在器件的分子成分的方法。参与这项研究的学生将接受现代实验物理化学技术的培训，从事与生物过程有关的研究问题，以及纳米技术和工程。其中最重要的反应之一是取代环己二烯在许多分子开关中具有活性的电环开环反应。对含环己二烯小分子的基础研究将为协同关系的理论研究提供实验数据。研究7-脱氢胆固醇的开环反应是很重要的，因为这正是发生在人体皮肤中产生维生素d前的反应。光引发的开环反应将在脂质体中进行研究，这是一个生理学相关的模型系统。该项目还寻求增加对分子马达关键的顺-反异构化反应的基本理解。钴胺素的光化学反应在传感器、抗维生素和分子给药装置中得到越来越多的应用。对活性钴胺的超快内部转化和光解的基础研究将进行，以了解这些系统的光化学和光物理作为配体，波长，温度和环境的函数。

With this award, the Chemical Structure, Dynamics and Mechanisms (CSDM-A) Program of the Division of Chemistry is funding Professor Sension of the University of Michigan, Ann Arbor to investigate molecular-based components of optically controlled nanomachines. These devices aim to provide a means for nanoscale remote-controlled sensing, transport, synthesis, memory, logic circuits, and information storage. The practical development of these devices faces significant challenges in design, arising from incomplete knowledge of the complicated systems involved. Professor Sension will use ultrafast spectroscopy to study the fundamental chemistry and physics of molecular processes relevant to molecular switches based on photochemical ring-opening reactions, molecular motors, based on isomerization around a central bond, and vitamin B12 analogues capable of photoactivated drug delivery. Methods will also be developed to use the wavelength, energy, phase, beam profile, polarization, and temporal structure of laser pulses intelligently to manipulate molecular constituents of potential devices. Students engaged in this research will receive training in modern experimental physical chemistry techniques, working on research problems relevant to biological processes, as well as nanotechnology and engineering. One of the most important reactions is the electrocyclic ring-opening reaction of substituted cyclohexadiene active in many molecular switches. Fundamental studies of small cyclohexadiene containing molecules will provide experimental data to inform theoretical efforts in a synergistic relationship. Study of the ring-opening reaction of 7-dehydrocholesterol is important as this is precisely the reaction that occurs in human skin to produce pre-vitamin D. The photoinitiated ring-opening reaction will be studied in liposomes, a physiologically relevant model system. This project also seeks to increase the fundamental understanding of cis-trans isomerization reactions key to molecular motors. The photochemical reactions of cobalamins are finding increased application in the sensors, antivitamins, and molecular drug-delivery devices. Fundamental studies of the ultrafast internal conversion and photodissociation of active cobalamins will be performed to understand the photochemistry and photophysics of these systems as a function of ligand, wavelength, temperature, and environment.