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

在分子水平上开发新材料代表了技术的下一个巨大进步，超越了驱动当前技术的小型化固态器件。可以在分子水平（即皮米尺度）上运行的设备比目前可用的最小集成电路的存储密度增加了一千倍。最引人注目的进步可以期待在传感器的发展，以极大的选择性监测无数的过程。实现这些目标需要许多人的技能，但必须包括化学家的主要贡献，他们既能产生新类型的分子，又能了解其性质：颜色、物理特性、电场磁化率、磁态等。***我的研究项目通过研究从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，为实现这一目标做出了贡献。本文所描述的工作有两个主要焦点：(i)目标物质的化学合成的进展和（ii）对添加和/或去除电子的后果的详细研究。这些新材料包含不同的成分，通常是“供体”和“受体”。一个项目将根据第五组元素对一系列供体进行精心设计的修改，将设计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采用二价碳的供体进行同样的研究。在第三个项目中，这些供体将与来自III族元素的受体一起进行审查，这些受体已证明有能力加速二氢的加入或去除。在这里，电子转移可以探测到这些转变的驱动力。我还建议对一类电子离域的V族和VI族元素化合物进行类似的分析，这些化合物作为具有金属受体的供体，其中电子转移的程度不能直接量化。这种“非无辜”实体的电反应是它们真实电子状态的指示器。此外，这些实体与一种独特的铬化合物的相互作用有望发挥电场依赖开关的作用，通过电位的应用开启活性。***我使用惰性气氛室进行合成和测量。分子结构最重要的是通过单晶x射线衍射方法确定。电气工作采用特殊的电路，能够以高度可控的方式改变施加的电压，并以高精度测量非常小的电流。表征在电路/化学界面的物质涉及探测可见光/紫外光，特别是电子顺磁共振波谱。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.