Adaptation and Self-Regulation in Multichromophoric Molecules

美国国家科学基金会化学部的有机化学和高分子化学项目支持亚利桑那州立大学的德文斯·J·古斯特、安娜·L·摩尔和托马斯·A·摩尔教授的一个研究项目，该项目涉及合成和研究复杂分子，包括共价连接的发色团、电子供体和受体，以及光致变色分子，这些分子在光照下会改变其结构。这些组分中的每一个都可以通过分子内能量和电子转移与其他组分交换信息。正是这些相互作用使复杂的现象得以出现。几种不同类型的分子体系被认为是最有希望进行研究的。在其中一个系统中，古斯特教授和他的合作者将设计、合成和光谱研究吸收光的分子，并将其以电荷分离状态的形式转化为电化学能，就像光合作用反应中心所发生的那样。在另一门课程中，我们将学习“分子三极体”及其相关结构。在这些情况下，光诱导的输出，如荧光或光致电荷分离，将被分子吸收的第二波长的光调制。这些分子将是电子三极管放大管或晶体管的类似物，它们的设计将挑战我们对影响分子内能量和电子转移的因素的理解。最后，最近已经证明，地球磁场影响光诱导分子内电子转移形成的双自由基态的寿命。这一发现可能有助于揭示鸟类和其他哺乳动物如何利用地球磁场导航。然而，观察到的效应的化学基础还不清楚。古斯特教授和他的合作者将与牛津大学的研究人员合作，准备和研究旨在揭示这一机制的新分子。这项拟议研究的广泛影响将导致对新兴现象的更好理解，这是一个跨越化学、物理和生物学许多领域的话题。这项研究将涉及本科生、研究生和博士后。特别重要的是培养传统上在化学方面代表性不足的群体的学生。一些招聘和培训将与WAESO(西部扩大学生机会联盟)的几个单位合作，WAESO是以亚利桑那州立大学为中心的NSF-LSAMP项目。此外，还将与几所拉丁美洲大学建立正式和非正式的研究型学生交流计划。经验表明，来自拉丁美洲的才华横溢、成绩斐然的学生是国内拉美裔学生的优秀榜样，为他们提供了实现潜力所需的指导和信心。与几所欧洲大学的非正式学生交换计划目前已经到位，并将在新项目中继续和扩大。

The Organic and Macromolecular Chemistry Program in the Chemistry Division at the National Science Foundation supports Professors Devens J. Gust, Anna L. Moore and Thomas A. Moore of Arizona State University for a research project that involves the synthesis and study of complex molecules consisting of covalently linked chromophores, electron donors and acceptors, and photochromic molecules that change their structure upon exposure to light. Each of these components can exchange information with others via intramolecular energy and electron transfer. It is these interactions that will allow complex phenomena to emerge. Several different classes of molecular systems have been identified as most promising for study. In one of these systems, Professor Gust and his collaborators will design, synthesize, and spectroscopically investigate molecules that absorb light and convert it to electrochemical energy in the form of a charge-separated state, as occurs in photosynthetic reaction centers. In another, "molecular triodes" and related structures will be studied. In these, a light-induced output such as fluorescence or photoinduced charge separation will be modulated by a second wavelength of light that is also absorbed by the molecule. These molecules will be analogs of electronic triode amplifier tubes or transistors, and their design will challenge our understanding of the factors influencing intramolecular energy and electron transfer. And finally, it has been recently demonstrated that the earth's magnetic field affects the lifetime of biradical states formed by light-induced intramolecular electron transfer. This discovery may help uncover how birds and other mammals can navigate using the earth's magnetic field. However, the chemical basis of the observed effect is not yet understood. Professor Gust and collaborators will prepare and study new molecules designed to uncover the mechanism in collaboration with researchers at the University of Oxford.Broader impacts of the proposed research will be results that lead to a better understanding of emergent phenomena, a topic that cuts across many fields of chemistry, physics and biology. The research will involve students at the undergraduate, graduate and postdoctoral levels. Of special importance is the training of students from groups traditionally underrepresented in chemistry. Some of the recruiting and training will be in collaboration with several units of WAESO, (Western Alliance to Expand Student Opportunities), an NSF-LSAMP program centered at Arizona State University. Additionally, formal and informal programs for exchange of research students will be instituted with several Latin American universities. Experience has shown that highly-talented, successful students from Latin America serve as excellent role models for domestic Hispanic students, giving them the guidance and confidence necessary to achieve their potential. Informal student exchange programs with several European universities are currently in place, and will be continued and expanded in the new project.