CAREER: Magnetostructural Correlations in Rare Earth - Transition Metal Pnictides and Tetrelides

本项目由DMR固态与材料化学项目资助，研究影响固态材料磁性行为的化学因素。项目的第一部分重点研究具有thcr2si2型结构的稀土过渡金属磷化物和砷化物的磁结构相关性和异常磁性行为。总体目标是了解化学修饰如何影响这些相的结构和磁性，这些相根据稀土和过渡金属的性质表现出截然不同的磁性行为。目标材料与基于feas的等结构超导体密切相关，预计这部分项目的发现也将提供与其他重要材料类别相关的知识。该项目的第二部分使用探索性合成来发现Ln-T-X体系中富含镧系元素的磁相（Ln =稀土金属；T =过渡金属；X = P, As, Ge, Sn）。在这种三元图中，富稀土部分很少有相被报道，而对Ln含量为40%的成分的广泛探索可能会发现具有突出磁性能的新材料。研究这些材料的结构、电子和磁性之间的相关性将有助于我们理解局域f电子和流动d带磁性之间的复杂相互作用。DMR的固态和材料化学项目支持寻找具有改进性能的磁性固体，这需要对晶体结构和磁性行为之间的相关性有基本的了解。提出的研究旨在探索这种关系，并制备具有潜在前景的新材料。这些目标将通过化学改性材料来控制其磁性行为和使用创新的合成方法来发现新的磁体来实现。该项目将为固态化学、晶体学和磁学领域的研究生和本科生提供培训。研究目标与材料化学创新课程的发展交织在一起。作为项目的一部分，将实施一系列视觉材料，为本科生和高中生介绍材料研究的工具方法。

TECHNICAL SUMMARYThis project supported by the Solid State and Materials Chemistry program in DMR studies chemical factors that influence magnetic behavior of solid state materials. The first part of the project focuses on investigation of magnetostructural correlations and anomalous magnetic behaviors in rare-earth transition metal phosphides and arsenides with the ThCr2Si2-type structure. The overall goal is to understand how chemical modifications impact the structural and magnetic properties of these phases, which exhibit dramatically different magnetic behavior depending on the nature of the rare-earth and transition metals. The targeted materials are closely related to the isostructural FeAs-based superconductors, and it is expected that findings from this part of the project will also provide knowledge that is relevant to other important classes of materials. The second part of the project uses exploratory synthesis for discovery of lanthanide-rich magnetic phases in Ln-T-X systems (Ln = rare-earth metal; T = transition metal; X = P, As, Ge, Sn). Very few phases have been reported in the rare-earth rich part of such ternary diagrams, and the extensive exploration of compositions with 40% content of Ln may uncover new materials with prominent magnetic properties. The study of correlations between structural, electronic, and magnetic properties of these materials will contribute to our understanding of complex interactions between the localized f-electrons and itinerant d-band magnetism.NON-TECHNICAL SUMMARYThe Solid State and Materials Chemistry program in DMR supports the search for magnetic solids with improved performance which requires fundamental understanding of correlations between the crystal structure and magnetic behavior. The proposed research is directed at the exploration of this relationship and preparation of new materials with potentially promising magnetic properties. These goals will be achieved through chemical modification of materials to control their magnetic behavior and the use of innovative synthetic approaches for the discovery of new magnets. The project will provide training for graduate and undergraduate students in the fields of solid state chemistry, crystallography, and magnetism. The research objectives are intertwined with the development of an innovative curriculum in materials chemistry. As a part of the project, a series of visual materials will be implemented to provide an introduction to instrumental methods in materials research for both undergraduate and high-school students.