High Spin Organic Molecules and Materials

该奖项是在化学部的有机动力学项目中颁发的，以支持加州理工学院丹尼斯·多尔蒂博士的研究。这项研究将继续多尔蒂的工作，设计、合成和表征基于复杂杂环和/或自由基离子的自旋耦合和二、三自由基模型，其中含有自旋的部分由铁磁耦合单元连接，这确保通过它连接的任何两个或更多自旋将经历高自旋铁磁耦合而不是低自旋反铁磁耦合。间苯二烯将是主要的偶联单元。具有高自旋基态和对低自旋激发态具有较大能隙的自由基体系将是组装成具有可控拓扑结构的高度交联有机网络的候选对象，以确保良好的磁耦合。构建扩展网络的策略将包括合成封闭壳聚合物或网络，对其进行充分表征，然后通过化学或电化学掺杂过程引入自旋。磁性能将通过变温SQUID磁测量和电子顺磁共振测量来表征。这项高度跨学科的研究解决了简单模型多自由基体系中自旋-自旋相互作用的基本问题，以及如何将它们应用于扩展的大块有机磁体。该项目成功的关键将是带隙工程，它将确保在环境条件下的高自旋基态。磁性材料在现代技术中无处不在。有机磁体将在轻质电机和信息存储系统中找到潜在的应用。

This award is made in the Organic Dynamics Program in the Chemistry Division in support of the research of Dr. Dennis Dougherty at the California Institute of Technology. The research will continue Dougherty's efforts on the design, synthesis, and characterization of model spin- coupled and di- and tri-radicals based on complex heterocycles and/or radical ions where the spin-containing moieties are connected by a ferromagnetic coupling unit which ensures that any two or more spins linked through it will experience high spin ferromagnetic coupling rather than low spin antiferromagnetic coupling. Meta-phenylene will be the primary coupling unit. Radical systems which have high spin ground states and a large energy gap to low spin excited states will be candidates for assembly into highly cross linked organic networks with controlled topologies to ensure favorable magnetic coupling. Strategies for building extended networks will involve synthesizing closed shell polymers or networks, fully characterizing them, and then introducing spins by a chemical or electrochemical doping procedure. Magnetic properties will be characterized by variable temperature SQUID magnetometry and electron paramagnetic resonance measurements. This highly interdisciplinary research addresses fundamental issues of spin-spin interactions in simple model polyradical systems and how they can be applied to extended bulk organic magnets. Critical to the success of the project will be band gap engineering which will assure high spin ground states at ambient conditions. Magnetic materials are ubiquitous in modern technology. Organic magnets will find potential applications in light weight motors and information storage systems.