CAS: Hard Permanent Magnets Through Molecular Design

CAS：通过分子设计实现硬质永磁体

• 批准号: 2206534
• 负责人: Jeffrey Long
• 金额: $ 57.7万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-08-01 至 2025-07-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2206534&HistoricalAwards=false
• 关键词: CAS; Hard; Permanent; Magnets; Through

PART 1: NON-TECHNICAL SUMMARYMagnetism is a scientific concept that penetrates society in myriad aspects of daily life, from the magnets in electric motors, to portable electronics, to scanners for diagnostic medical imaging. With this project, supported by the Solid State and Materials Chemistry Program in NSF’s Division of Materials Research, researchers at the University of California (UC) Berkeley create new magnetic materials whose design is tailored at the atomic level. The research significantly advances our knowledge and understanding of permanent magnet materials, in particular how to synthesize them through molecular design principles. The research could be transformative in that it offers the potential to inform the design and manufacture of new magnets with superior properties relative to the current state-of-the-art. At a more fundamental level, the research has significant impact in the areas of magnetic materials, materials chemistry, and metal–organic frameworks. In addition, many researchers engaged in the disciplines of condensed matter physics, conductive materials, and quantum information science can also benefit from the new insights gained by the research. Beyond these scientific benefits, this project broadly expand its impact by creating educational opportunities for the general public, specifically through the production of educational outreach program branching off an existing collaboration, where graduate students from UC Berkeley produce lessons on magnetic materials for Bay Area elementary school students. This outreach program is intended to reach large numbers of K-12 students that constitute diverse backgrounds.PART 2: TECHNICAL SUMMARYAs part of this project, supported by the Solid State and Materials Chemistry Program in NSF’s Division of Materials Research, researchers at UC Berkeley test the hypothesis that the design principles governing magnetic anisotropy in molecules can inform the design of ultrahard permanent magnet materials. Specifically, work from many research groups over the past two decades has uncovered how coordination chemistry can be applied to tailor geometric and electronic structures of molecules with atomic precision, to maximize the single-ion magnetic anisotropy—the fundamental source of the strength, or “hardness”, of a permanent magnet. This project employs these design principles to incorporate selected classes of high-anisotropy molecules—in particular high-performance single-molecule magnets—into metal–organic framework materials. Both transition metal- and lanthanide (Ln)-based molecular building units are pursued, falling into four main classes: (i) mixed-valence Ln2X3 cores with immense coercivity, (ii) low-valent lanthanide complexes with populated 5d orbitals, (iii) two- and three-coordinate transition metal complexes, and (iv) trigonal paddlewheel complexes. To install strong coupling interactions between these high-anisotropy nodes, two synthetic strategies are utilized: (i) high-energy organic linker-based spins and (ii) electron delocalization in mixed-valence materials. The students and postdoctoral researchers who carry out this research receive training in the synthesis of and characterization of framework materials, including sophisticated physical methods such as magnetometry, x-ray diffraction, and Mössbauer spectroscopy. Moreover, these researchers regularly interact with collaborators in other research groups, both at Berkeley and other institutions. This collaborative culture fosters an open and inclusive forum for scientific advancement, and aids in the professional development and teamwork skills of the involved researchers.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.

第一部分：非技术概述磁性是一个科学概念，渗透到社会日常生活的各个方面，从电动机中的磁铁到便携式电子产品，再到诊断医学成像的扫描仪。在NSF材料研究部门的固态和材料化学项目的支持下，加州大学伯克利分校的研究人员创建了新的磁性材料，其设计在原子水平上定制。这项研究大大提高了我们对永磁材料的认识和理解，特别是如何通过分子设计原理合成它们。这项研究可能是变革性的，因为它提供了潜在的信息，设计和制造新的磁铁与上级性能相对于当前的最先进的水平。在更基础的水平，研究在磁性材料，材料化学和金属有机框架领域有重大影响。此外，许多从事凝聚态物理、导电材料和量子信息科学的研究人员也可以从研究中获得的新见解中受益。除了这些科学效益，该项目通过为公众创造教育机会，特别是通过现有合作的教育推广计划分支的生产，广泛扩大其影响，其中来自加州大学伯克利分校的研究生为湾区小学生制作磁性材料课程。第2部分：技术总结作为该项目的一部分，由美国国家科学基金会材料研究部的固态和材料化学项目支持，加州大学伯克利分校的研究人员测试了一种假设，即控制分子中磁各向异性的设计原理可以为超硬永磁材料的设计提供信息。具体来说，在过去的二十年里，许多研究小组的工作已经揭示了配位化学如何应用于以原子精度定制分子的几何和电子结构，以最大限度地提高单离子磁各向异性永磁体强度或“硬度”的基本来源。本计画利用这些设计原则，将选定类别的高异向性分子，特别是高效能的单分子磁铁，纳入金属有机骨架材料中。过渡金属和镧系元素（Ln）为基础的分子构建单元，分为四个主要类别：（i）混合价Ln2X3核心与巨大的双折射率，（ii）低价镧系元素配合物与填充5d轨道，（iii）两个和三个协调的过渡金属配合物，和（iv）三角桨轮配合物。为了在这些高各向异性节点之间安装强耦合相互作用，利用两种合成策略：（i）基于高能有机连接体的自旋和（ii）混合价材料中的电子离域。进行这项研究的学生和博士后研究人员接受框架材料合成和表征方面的培训，包括复杂的物理方法，如磁力测量，X射线衍射和穆斯堡尔光谱。此外，这些研究人员经常与伯克利和其他机构的其他研究小组的合作者互动。这种合作文化为科学进步培养了一个开放和包容的论坛，并有助于参与研究人员的专业发展和团队合作技能。该奖项反映了NSF的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。