Redox Active Compounds & Non-innocent Ligands: Synthesis, Structure, Electrochemistry, EPR Spectroelectrochemistry

分子水平上新材料的开发代表着技术上的下一次重大进步，超越了驱动当前技术的微型固态设备。能够在分子级别(也就是皮秒级)工作的器件，其存储密度比目前可用的最小集成电路高出一千倍。可以预期，最引人注目的进步将出现在以极高选择性监控无数过程的传感器的开发方面。实现这些目标将需要许多人的技能，但必须包括化学家的主要贡献，他们既生产新型分子，又了解性质：颜色、物理特征、电场易感性、磁态等。*我的研究计划通过研究含有新元素组合的材料中添加和移除电子的能量学和机制来为这一目标做出贡献。这里描述的工作有两个主要重点：(1)目标物种化学合成的进展和(2)对添加和/或去除电子的后果的详细调查。这些新材料包含不同的组成部分，通常是“捐赠者”和“接受者”。其中一个项目将根据V组元素对一系列施主进行精心设计的修改，将设计中的结构与电子转移倾向联系起来。另一项研究将对最近一类使用二价碳的捐赠者进行同样的研究。在第三个项目中，这些供体将与来自第三族元素的接受者一起接受检查，这些第三族元素已证明有能力加速氢气的添加或去除。在这里，电子转移可以探测这些转变的驱动力。我还建议对一类电子离域的V和VI族元素化合物进行类似的分析，因为它们是带有金属受主的给体，其中的电子转移程度无法直接量化。这些“非无辜”实体的电反应是其真实电子状态的指标。此外，这些物质与一种独特的铬化合物的相互作用有望发挥电场相关开关的作用，通过施加电势来启动活动。*我使用惰性气氛小室进行合成和测量。最重要的是用单晶X射线衍射法来确定分子结构。电气工作采用特殊电路，能够以高度受控的方式改变施加的电压，并以高精度测量非常小的电流。电路/化学界面物种的表征涉及用可见光/紫外光，特别是电子顺磁共振光谱进行探测。完成这项工作所需的所有主要工具都已到位。

The development of new materials at the molecular level represents the next great advance in technology beyond the miniaturized solid-state devices that drive current technology. Devices that could operate at the molecular level (that is, on the picometer scale) offer a thousand-fold increase in storage density over the smallest integrated circuits available today. The most spectacular advances can be expected in development of sensors that monitor a myriad of processes with great selectivity. Achieving these goals will require the skills of many, but must include major contributions by chemists who both produce new kinds of molecules and gain understanding of properties: colour, physical characteristics, electric field susceptibility, magnetic states, etc.***My research program contributes to this goal by studying the energetics and mechanisms of adding and removing electrons from materials that contain new combinations of elements. The work described herein has two major foci: (i) advances in chemical synthesis of targeted species and (ii) detailed investigations of the consequences of adding and/or removing electrons from them. These new materials contain distinct components, typically `donors' and `acceptors'. One project will prepare carefully designed modifications to a series of donors based on a Group V element, relating the designed-in structures to the propensity for electron transfer. Another will examine the same for a more recent class of donors employing divalent carbon. In a third project, such donors will be examined along with acceptors from Group III elements, which have demonstrated ability to accelerate the addition or removal of dihydrogen. Here electron transfer can probe the driving forces for these transformations. I also propose to perform similar analyses on a class of electron-delocalized Group V and VI element compounds as donors with metallic acceptors in which the degree of electron transfer is not directly quantifiable. The electrical response of such `non-innocent' entities is an indicator of their true electronic state. Furthermore, the interaction of these entities with a unique chromium compound is expected to be able to function as an electric-field-dependent switch, turning activity on with the application of an electrical potential.***I employ inert-atmosphere chambers for synthesis and measurement. Molecular structures are determined most importantly by single-crystal X-ray diffraction methods. Electrical work employs special circuitry capable of varying the applied voltage in a highly controlled manner and measuring very small currents with high precision. Characterization of species at the circuit/chemistry interface involves probing with visible/ultraviolet light and especially electron paramagnetic resonance spectroscopy. All the required major instruments to perform this work are in place.