Spectroscopic Investigations of Molecular Quantum Materials. Probing Spin-Phonon Couplings and Intermolecular Magnetic Interactions

在该项目中，由化学系化学结构，动力学机制B计划资助，田纳西大学化学系的薛子凌教授正在研究分子量子材料在超高密度数据存储，量子计算和低温磁制冷方面的潜在应用。预计这种材料的存储容量将比目前的存储材料大得多，可能会导致更高效的计算机和制冷设备。 该项目的具体目标是探索材料的特性，以确定对其性能负责的因素。 该项目是跨学科的，涵盖无机，物理和材料化学。 它为学生提供了在国家实验室进行研究的不寻常的机会，这有助于扩大他们的教育背景和培训。 PI还致力于吸引高中生考虑从事科学研究，特别强调来自低收入家庭的潜在第一代大学生。慢磁弛豫是与分子量子材料相关的应用中的关键特性。目前的研究工作主要集中在设计和制备具有大的各向异性和缓慢弛豫的化合物。 对于自旋-声子耦合和分子间磁相互作用的性质，人们的理解相对较少，而这也是导致磁弛豫的主要因素。 在这个项目中，分子量子材料将使用几种非常规的光谱学来回答以下问题：（i）四维（4D）非弹性中子散射（INS）能否揭示分子化合物中的自旋-声子耦合？(ii)在惯性导航系统中，磁峰对中子散射矢量的独特依赖性是否可以用来探测分子间的磁相互作用？(iii)远红外、拉曼、高场电子顺磁共振、脉冲电子顺磁共振和惯性导航系统的联合应用在多大程度上可以用来研究自旋-声子耦合？(iv)开发有效的量子比特（qubit）需要什么独特的自旋-自旋弛豫特性？ 在解决这些基本问题方面取得的进展有望成为化学界努力开发新系统的重要一步，这些新系统有可能作为量子计算或相关量子材料应用的量子比特。该奖项反映了NSF的法定使命，并被认为值得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来支持。

In this project, funded by the Chemical Structure, Dynamics & Mechanism B Program of the Chemistry Division, Professor Ziling Xue of the Department of Chemistry at the University of Tennessee is investigating molecular quantum materials with potential applications in ultra-high density data storage, quantum computation, and cryogenic magnetic refrigeration. Such materials are expected to have much larger storage capacities than the current storage materials, potentially leading to much more efficient computers and refrigeration devices. The specific goal of this project is to probe properties of the materials to identify the factors responsible for their performance. The project is interdisciplinary, covering inorganic, physical, and materials chemistries. It offers students unusual opportunities to conduct research at a national laboratory, which serves to broaden their educational background and training. The PI also works to attract high school students to consider pursuing studies in science with a particular emphasis on potential first generation college students from low income families .Slow magnetic relaxation is a critical property in applications related to molecular quantum materials. Current research efforts have been mostly focused on the design and preparation of compounds with large anisotropies and slow relaxation. There is relatively little understanding of the nature of spin-phonon couplings and intermolecular magnetic interactions, which are also main factors contributing to magnetic relaxation. In this project, molecular quantum materials will be studied using several unconventional spectroscopies to answer the following questions: (i) Can four-dimensional (4D) inelastic neutron scattering (INS) reveal spin-phonon coupling in molecular compounds? (ii) Can a magnetic peak’s unique dependence on the neutron scattering vector in INS be used to probe intermolecular magnetic interactions? (iii) To what degree can the combined use of far-infrared (IR), Raman, high-field electron paramagnetic resonance (EPR), pulsed EPR, and INS be used to study spin-phonon coupling? (iv) What are unique spin-spin relaxation properties are needed to develop effective quantum bits (qubits)? Progress in addressing these fundamental questions is expected to be an important step in the effort of the chemistry to develop new systems that have the potential to serve as quantum bits for quantum computing or related quantum materials applications.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.