RUI: Photochemistry and Photophysics of Macrocyclic Chromium(III) Complexes: An Investigation of Electronic Energy Self-Exchange

这个无机、生物无机和有机金属化学项目的RUI奖支持弗曼大学的Paul S. Wagenknecht教授更好地理解类似物质之间的能量转移以及热力学对近热中性能量转移反应的影响。将研究诸如反式- [Cr(N4)(CN)2]+配合物（其中N4 =四氮杂环配体）这样的系统，其中的热中性能量转移可能至少比它们的吸热或放热对应物快一个数量级。几种类型的新大环Cr（III）配合物（其中一些具有可调激发态性质）将被制备并用于能量转移研究，以回答以下问题：这种速率峰值发生的能量区域有多窄？这种现象有多普遍？热中性情况下加速速率的解释是什么？在氰化物配体的位置，取代的苯乙酰基配体将被使用，以便光行为可以通过取代苯乙酰基调整。利用脉冲激光激发和斯特恩-沃尔默分析对新配合物的光物理和能量转移特性进行表征。该项目将提供与替代能源领域相关的基础数据，并将让本科生参与基础光化学研究。

This RUI award in the Inorganic, Bioinorganic and Organometallic Chemistry program supports Professor Paul S. Wagenknecht at Furman University to develop a better understanding of energy transfer between like species and the effect of thermodynamics on nearly thermoneutral energy transfer reactions. Systems such as trans- [Cr(N4)(CN)2]+ complexes (where N4 = a tetraazamacrocylic ligand), in which the thermoneutral energy transfers may be at least an order of magnitude faster than either of their endothermic or exothermic counterparts, will be studied. New macrocyclic Cr(III) complexes (some with tunable excited state properties) of several types will be prepared and utilized in energy transfer studies to answer the following questions: How narrow is the energy region over which this spike in rate occurs? How general is this phenomenon? What is the explanation for the accelerated rate in the thermoneutral case? In place of the cyanide ligand, substituted phenylacetylide ligands will be employed so that the photobehavior can be tuned via substitutions on the phenylacetylide. The new complexes will be characterized as to their photophysics and energy transfer properties by using pulsed-laser excitation and Stern-Volmer analyses. This project will provide fundamental data relevant to the field of alternative energy sources and will involve undergraduates in basic photochemical research.