EAGER: Probing Single-Ion Magnets by Raman and Far-Infrared Spectroscopies

美国田纳西大学化学系薛子凌教授在化学系化学结构与动力学机制B项目的资助下，正在开发光谱学方法来表征具有有趣磁性的新型金属化合物。我们的目标是了解这些金属络合物的磁性，以便将它们开发成高密度数据存储和量子计算的新材料。磁性金属化合物可以具有比当前数据存储材料大得多的存储容量，显著节省能源并减少对环境的影响。该项目是跨学科的，涉及无机，物理和材料化学。它特别适合于不同层次的研究人员的教育。该项目还将为学生提供在国家实验室进行研究的机会，并扩大他们的教育培训。薛教授的研究小组有能力为科学领域的弱势学生（包括来自低收入家庭的第一代大学生）提供高水平的教育和培训。单离子磁体（西姆斯）由于表现出缓慢的磁弛豫和量子隧穿现象而受到积极研究。在西姆斯的离散分子中定向分子自旋的各向异性势垒足够大以显示磁滞。已经有积极的研究努力来设计/制备具有大的各向异性和缓慢弛豫的西姆斯。西姆斯中的磁基态和激发态之间的大分离与大的各向异性和慢弛豫密切相关。这是一个挑战，以精确地确定磁基态和激发态之间的分离，当分离超过50波数，并光谱探测磁声子相互作用导致自旋晶格弛豫。该项目研究直接确定西姆斯中超过50个波数的磁分离和探测磁-声子相互作用的方法。 磁场中的拉曼和远红外光谱将用于表征西姆斯，表明光谱可以发展成为探测分子磁性的有效方法。

In this project funded by the Chemical Structure, Dynamic & Mechanism B Program of the Chemistry Division, Professor Ziling (Ben) Xue in Department of Chemistry, University of Tennessee-Knoxville, is developing spectroscopic methods to characterize new classes of metal compounds with interesting magnetic properties. The goal is to understand the magnetic properties of these metal complexes in order to develop them into new materials for high-density data storage and quantum computing. The magnetic metal compounds could have a much larger storage capacity than the current data storage materials with significant energy savings and reduced environmental impacts. The project is interdisciplinary involving inorganic, physical, and materials chemistry. It is particularly suited to the education of researchers at different levels. The project will also offer students opportunities to conduct research at a national laboratory and broaden their educational training. Professor Xue's group is well-positioned to provide the high level of education and training for students underrepresented in science, including first-generation college students from low-income families.Single-ion magnets (SIMs) have been actively studied as they have demonstrated slow magnetic relaxation and quantum tunneling phenomenon. Anisotropy barriers to orientate molecular spins in discrete molecules of SIMs are large enough to display magnetic hysteresis. There have been active research efforts to design/prepare SIMs with large anisotropies and slow relaxations. Large separations between magnetic ground and excited states in SIMs are closely related to the large anisotropies and slow relaxation. It is a challenge to precisely determine the separations between magnetic ground and excited states, when the separations are more than 50 wavenumbers, and to spectroscopically probe magneto-phonon interactions leading to spin-lattice relaxation. This project investigates ways to directly determine magnetic separations more than 50 wavenumbers in SIMs and to probe magneto-phonon interactions. Raman and far-infrared spectroscopies inside magnetic fields are to be used to characterize SIMs, demonstrating that the spectroscopies could be developed into effective methods to probe molecular magnetism.