CAREER: Rational Design of Magnetic Materials Featuring Low-Dimensional Subunits

非技术概述固态材料的磁性在包括发电机、电机、变压器、传感器和硬盘在内的众多现代设备的制造中起着至关重要的作用。此外，它们还具有进一步创新的潜力，因此，如果能够合理地合成具有目标磁性的新的磁性材料，将是非常有用的。在固态和材料化学计划的支持下，首席研究员的NSF职业资助将专注于将实验和理论相结合，以设计具有可调磁性能的新型过渡金属丰富的硼化物。该项目将实验和理论相结合，能够在随后的合成之前预测最激动人心的磁性材料，从而加速寻找与能源应用相关的新磁性材料。该项目为研究生和本科生提供培训，他们有很好的机会获得材料合成和计算方面的独特专业知识。学生培训的一部分还包括通过暑期研究机会参加外联活动，以激励来自附近城市莫雷诺山谷的高中生攻读STEM专业。莫雷诺山谷是一个少数民族占很大比例的城市。这个项目还有一个教育部分，旨在将新材料化学课程实施到这些莫雷诺山谷高中的化学课程中。技术总结这个NSF职业项目结合了实验和理论，旨在设计制备和彻底表征新的复杂过渡金属硼化物，其中预期结构变化与磁性行为的变化有关，如磁性有序转变和磁性受挫。要研究的第一类材料包括磁性活跃的过渡金属梯子与四个硼原子的线性团簇相互作用，这是一种意想不到的相互作用，可能会极大地影响这些材料的磁性。在第二类材料中，将研究导致一维、二维和三维亚结构的相互关联的铁三角团簇，这些亚结构是几何受阻的磁系。此外，预计将进行结构转型，并将对其进行调查。实验研究包括固态化学合成、晶体生长、元素分析、磁化测量以及X射线和中子衍射。密度泛函理论计算将用于研究实验发现的新化合物的电子结构、化学键和磁性，并预测新的合成目标。在这个项目中，实验和理论的结合将为研究生和本科生提供一个真正的跨学科问题。他们将学习实验和理论如何相互影响，以促进科学知识的发展。

Non-Technical SummaryThe magnetic properties of solid state materials play a crucial role in the manufacture of numerous modern devices including generators, motors, transformers, sensors, and hard discs. Also, they hold the potential for further innovation, thus it would be extremely useful if one could rationally synthesize new magnetic materials with targeted magnetic properties. With support from the Solid State and Materials Chemistry program, the Principal Investigator's NSF CAREER grant will focus on combining experiment and theory towards designing new transition metal-rich borides with tunable magnetic properties. The combination of experiment and theory in this project enables the prediction of the most exciting magnetic materials before they are subsequently synthesized, thereby accelerating the search for new magnetic materials relevant to energy applications. The project provides training for both graduate and undergraduate students, who have an excellent opportunity to acquire unique expertise in both materials synthesis and computation. Part of the students' training also includes participation in outreach activities through summer research opportunities to inspire high school students from the nearby city of Moreno Valley, which has a large percentage of minorities, to pursue STEM majors. This project also has an educational component which aims to implement a new materials chemistry class into the chemistry curriculum of these Moreno Valley high schools.Technical SummaryThis NSF CAREER project combines experiment and theory towards the designed preparation and thorough characterization of new complex transition metal-rich borides, in which structural transformations associated with changes in magnetic behaviors such as magnetic ordering transitions and magnetic frustration are anticipated. The first class of materials to be investigated contains ladders of magnetically active transition metals interacting with linear clusters of four boron atoms, an unforeseen interaction with the potential of drastically impacting the magnetic properties of these materials. In the second class of materials, interconnected iron triangular clusters leading to 1D, 2D and 3D substructures, which are geometrically frustrated magnetic systems, will be studied. Also, structural transformations are expected and will be investigated. Experimental investigations encompass solid state chemistry synthesis, crystal growth, elemental analysis, magnetization measurements, as well as X-ray and neutron diffraction. Density functional theory calculations will be used to study the electronic structure, chemical bonding and magnetic properties of the experimentally found new compounds and to predict new synthetic targets. The combination of experiment and theory in this project will provide the graduate and undergraduate students involved with a truly interdisciplinary problem. They will learn how experiment and theory impact each other towards advancing scientific knowledge.