Photophysics of Mono-Disperse Metal-Organic Oligomers

该基金属于无机、生物无机和有机金属化学项目，支持佛罗里达大学化学系Kirk S. Schanze博士对金属-有机偶联聚合物光学特性的研究。几个同源系列的单分散、金属有机偶联寡聚物的光物理性质将被确定为高分子量聚合物的模型。要研究的特定化合物是单分散的苯乙烯和苯乙烯型低聚物，它们含有联吡啶单元，可以结合各种过渡金属离子，特别是铼(I)和钌（II）。在这些化合物中观察到整个低聚物的低洼金属到配体电荷转移（MLCT）激发态离域。除了金属中心对光学性质的影响外，还将研究低聚物拓扑结构、共轭长度和带隙对MLCT激发态性质的影响。还将研究一些铂-乙酰醚低聚物。光物理研究将利用吸收、光致发光、光诱导吸收、瞬态FT-IR和FT-EPR光谱和光声量热法。金属有机聚合物表现出的特性是金属和有机组分的组合。由于这个原因，它们有潜力用于需要电致变色或光折射性的电子设备或金属离子的特定检测。参与该项目的研究生和本科生将获得许多合成技术和复杂仪器使用的经验。

This grant in the Inorganic, Bioinorganic, and Organometallic Chemistry Program supports research on the optical properties of metal-organic pi-conjugated polymers by Dr. Kirk S. Schanze of the Department of Chemistry, University of Florida. The photophysical properties of several homologous series of mono-disperse, metal-organic pi-conjugated oligomers will be determined as models for higher molecular weight polymeric counterparts. The specifc compounds to be studied are mono-disperse phenyleneethynylene and phenylenevinylene type oligomers that contain bipyridine units that can bind a variety of transition metal ions, particularly rhenium (I) and ruthenium (II). Low-lying metal to ligand charge transfer (MLCT) excited states delocalized over the entire oligomer are observed in these compounds. In addition to the impact of the metal center on optical properties, the effects of oligomer topology, conjugation length and bandgap on the properties of the MLCT excited states will be investigated. Some platinum-acetylide oligomers will also be studied. Photophysical investigation will utilize absorption, photoluminescence, photoinduced absorption, transient FT-IR and FT-EPR spectroscopies and photoacoustic calorimetry.Metal-organic polymers exhibit properties that are a combination of those expected for the metal and organic components. For this reason, they have potential for use in electronic devices that require electrochromism or photorefractivity or in specific detection of metal ions. Graduate and undergraduate students involved in this project will gain experience in many synthetic techniques and use of sophisticated instrumentation.