Stable High-Spin Polyradicals and Chiral pi-Conjugated Systems

稳定的高自旋多自由基和手性π共轭系统

• 批准号: 0718117
• 负责人: Andrzej Rajca
• 金额: $ 57.07万
• 依托单位: University of Nebraska-Lincoln
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2007
• 资助国家: 美国
• 起止时间: 2007-11-15 至 2011-10-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0718117&HistoricalAwards=false
• 关键词: Stable; Spin; Polyradicals; Chiral; pi

With this award, the Organic and Macromolecular Chemistry Program supports the work of Professor Andrzej Rajca of the University of Nebraska-Lincoln. This research consists of two areas directed toward the synthesis and characterization of stable high-spin poly-radicals (multiple unpaired electrons) and chiral (not superimposable on its mirror image) pi-conjugated systems. In the area of poly-radicals, high-spin organic molecules with very strong ferromagnetic coupling and with stability at ambient conditions will be synthesized and characterized. The research approach is based upon annelated pi-systems of poly-radicals, for which both nitrogen-centered radicals and nitroxide radicals will be used as carriers of electron spin. In the area of chiral conjugated systems, chiral helicenes with more than eleven ortho-fused aromatic rings and related highly annelated pi-systems, including radical cations of helicenes, will be synthesized and studied. These studies are designed to advance the development of organic magnets and of other materials based upon high-spin organic molecules and to provide an understanding of the principles governing the rational design of strongly chiral organic materials.The proposed research involves organic synthesis and comprehensive physical characterization of organic molecules, in particular magnetic measurements. These multidisciplinary studies are expected to provide important fundamental information that will contribute to development of lightweight organic magnets and of chiral materials with novel optical and electronic properties. A group of undergraduate, graduate and postdoctoral students, who will carry out these studies, will receive diverse training in physical organic chemistry, organic synthesis, solid-state chemistry, and magnetism. The research experience will promote learning, by approaching and solving complex problems. Furthermore, the materials obtained from this project will be made available to other research groups in the United States and abroad.

有了这个奖项，有机和高分子化学计划支持内布拉斯加大学林肯分校的Andrzej Rajca教授的工作。 本研究包括两个领域，分别针对稳定的高自旋多自由基（多个不成对电子）和手性（不能在其镜像上重叠）π共轭系统的合成和表征。 在多自由基领域，将合成和表征具有非常强的铁磁耦合和在环境条件下稳定的高自旋有机分子。研究方法是基于多自由基的稠合π系统，其中氮中心自由基和氮氧自由基将被用作电子自旋的载体。在手性共轭体系方面，将合成和研究具有多于11个邻位稠合芳环的手性螺烯和相关的高度稠合的π-体系，包括螺烯的自由基阳离子。 这些研究旨在促进有机磁体和基于高自旋有机分子的其他材料的发展，并提供对强手性有机材料的合理设计原则的理解。拟议的研究涉及有机合成和有机分子的综合物理表征，特别是磁性测量。 这些多学科的研究预计将提供重要的基础信息，将有助于开发轻质有机磁体和手性材料与新的光学和电子性能。 一组本科生，研究生和博士后学生，谁将进行这些研究，将接受物理有机化学，有机合成，固态化学和磁性的各种培训。 研究经验将促进学习，通过接近和解决复杂的问题。 此外，从该项目获得的材料将提供给美国和国外的其他研究小组。