Materials World Network: Designed Preparation, Characterization, Magnetic Properties and Quantum Chemical Calculations of New Complex Itinerant Magnets, Ti(8-x)M(3+x)Ru(18-y)Rh(y)B

材料世界网络：新型复杂流动磁体 Ti(8-x)M(3 x)Ru(18-y)Rh(y)B 的设计制备、表征、磁性和量子化学计算

• 批准号: 0806507
• 负责人: Gordon Miller
• 金额: $ 22.8万
• 依托单位: Iowa State University
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-08-01 至 2012-07-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0806507&HistoricalAwards=false
• 关键词: Materials; World; Network; Designed; Preparation

This project combines experiment and theory towards the designed preparation and subsequent characterization and thorough understanding of new intermetallic ferromagnets and antiferromagnets. It is based on collaboration between Iowa State University and RWTH Aachen in Germany. The primary concept involves using a complex 4d metal-boride framework with magnetic 3d elements, e.g., Cr, Mn, Fe, Co and Ni, inserted in voids to create magnetic structures with potentially low-dimensional character. The metal-boride framework provides a structurally strong and electronically robust network for insertion of magnetic metals into channels. Furthermore, the metal-boride structure is intrinsically metallic, which provides a mechanism for magnetic exchange between adjacent magnetic metal atoms via the spins on the conduction electrons. Specifically, these materials are studied by X-ray and neutron diffraction as well as magnetization experiments to determine atomic and magnetic structures. Theoretical determination of the electronic structures on various models of these structures provides feedback toward further synthetic efforts of atomic substitutions to create new compounds with targeted magnetic behavior. At present, chemists and materials scientists have no general, yet simple, rules for targeting and tailoring ferromagnetic, intermetallics compounds, i.e., metallic compounds with permanent magnetic behaviour. This effort allows chemists to study an evolution of magnetic behaviour within a single structural family to identify trends in magnetic behavior as various chemical and physical parameters change in systematic ways. A project such as this, that combines experiment and theory for condensed matter systems, provides students a truly interdisciplinary problem - these students learn how different scientific subjects and models impact other scientific areas. The student participants in this project in Aachen, Germany and Ames, Iowa have opportunities for exchange, and they learn both experimental and theoretical components of research in solid-state chemistry. Furthermore, through this systematic study of a structural family, a set of rules will be generated for targeting metallic, permanent magnets, which have numerous technological applications. The real challenge will be to identify the temperature range where such targeted materials will show permanent magnetic behavior. In summary, this effort represents a strong, synergistic coupling of experiment and theory that targets new magnetic materials, and may lead to new materials with unusual bulk magnetic properties due to the potential one-dimensional character of the magnetic exchange.

本计画结合实验与理论，针对新型金属间铁磁体与反铁磁体的设计制备与后续表征，以及深入了解。 它是基于爱荷华州州立大学和德国的亚琛工业大学之间的合作。主要概念涉及使用具有磁性3d元件的复杂4d金属硼化物框架，例如，Cr、Mn、Fe、Co和Ni，插入空隙中以产生具有潜在低维特征的磁性结构。 金属-硼化物框架提供了用于将磁性金属插入通道中的结构坚固且电子稳健的网络。 此外，金属-硼化物结构本质上是金属的，这提供了通过传导电子上的自旋在相邻磁性金属原子之间进行磁交换的机制。 具体而言，这些材料通过X射线和中子衍射以及磁化实验来研究，以确定原子和磁性结构。 对这些结构的各种模型的电子结构的理论确定提供了对原子取代的进一步合成努力的反馈，以创建具有目标磁性行为的新化合物。 目前，化学家和材料科学家还没有针对和定制铁磁金属间化合物的一般但简单的规则，即，具有永久磁性的金属化合物。 这一努力使化学家能够研究单个结构家族中磁性行为的演变，以确定磁性行为的趋势，因为各种化学和物理参数以系统的方式变化。 像这样的项目，结合凝聚态系统的实验和理论，为学生提供了一个真正的跨学科问题-这些学生学习不同的科学科目和模型如何影响其他科学领域。 在德国的亚琛和爱荷华州的艾姆斯参加这个项目的学生有机会进行交流，他们学习固态化学研究的实验和理论组成部分。 此外，通过对结构族的系统研究，将产生一套针对金属永磁体的规则，这些规则具有许多技术应用。 真实的挑战将是确定这种目标材料将显示永磁行为的温度范围。 总之，这一努力代表了针对新磁性材料的实验和理论的强有力的协同耦合，并且由于磁交换的潜在一维特性，可能导致具有不寻常的大块磁性的新材料。