New Fluoride and Oxyfluoride Materials – Targeting Magnetic and Optical Properties

含有不同化学元素的非技术材料具有广泛的实用性和日常属性，并且可以在LED灯泡等基本设备中找到。这些特性包括光学和磁性行为，特别是在含氟材料中发现，并用于许多需要发光才能发挥作用的应用。例子包括LED灯泡中的涂层，国土安全的辐射探测器和医疗X射线扫描仪。 对于许多光学应用，必须获得单晶形式的材料。该研究由NSF材料研究部门的固态和材料化学计划支持，因此，通过开发新的方法来生长这种晶体，并通过优化化学成分来获得具有所需特性的材料，从而实现新型氟化物材料的晶体生长。基础研究的重点是新型含氟材料的晶体生长，这些材料旨在表现出特定的特性，如发光，这可以找到广泛的应用，并可以造福于国家。作为这项研究的一部分，许多学生在化学科学方面接受了培训，涉及广泛的学生，包括那些来自代表性不足的群体，在材料化学研究实验室的经验。此外，本科生暑期课程允许代表性不足的少数民族参与研究，并教他们有关材料的化学，目的是专门招募他们进入南卡罗来纳州大学化学研究生课程。通过晶体生长发现材料的概念被应用于大幅增加新的氟化物和氟氧化物材料家族的数量，以开发新的功能材料。众所周知，复杂的氟化物材料对于依赖于它们的光学性质（例如发光和闪烁）的应用是重要的，而获得表现出磁阻挫的氟化物和氟氧化物结构的能力对于理解自旋液体和自旋冰行为是普遍感兴趣的。该研究项目的重点是开发新方法，以系统地合成和表征新类别的氟化物和氟氧化物材料，并研究其光学和磁性行为。具体而言，通过三种不同的合成路线（温和水热、超临界水热和助熔剂晶体生长）进行新氟化物和氟氧化物材料的晶体生长的优化，以产生新的磁性和光学材料。通过选择过渡和镧系元素并将其掺入新的氟化物和氟氧化物结构中来控制性能，其中含有过渡和镧系金属的那些用于研究磁性行为，含有镧系元素的那些用于研究光学性能。作为这项研究的一部分，许多学生在化学科学方面接受了培训，涉及广泛的学生，包括那些来自代表性不足的群体，在材料化学研究实验室的经验。此外，一个针对本科生的暑期项目允许代表性不足的少数民族参与研究，并向他们教授材料的化学，目标是专门招募他们进入南卡罗来纳州大学的化学研究生课程。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智力价值和更广泛的影响审查标准进行评估来支持。

Non-TechnicalMaterials containing different chemical elements exhibit a wide range of useful, everyday properties and are found in devices as basic as LED light bulbs. The properties, which include optical and magnetic behavior, are found especially in materials containing fluorine and are used for many applications that require the emission of light for them to function. Examples include coatings in LED light bulbs, radiation detectors for homeland security, and scanners for medical x-rays. For many optical applications it is necessary to obtain the materials in the form of single crystals. The research, supported by the Solid State and Materials Chemistry program in NSF’s Division of Materials Research, therefore, targets the crystal growth of new fluoride materials by developing new methods to grow such crystals and by optimizing the chemical compositions to obtain materials with the desired properties. The basic research focus is on the crystal growth of new fluorine-containing materials that are designed to exhibit specific properties, such as light emission, which can find widespread applications and can benefit the nation. As part of this research, numerous students are trained in the chemical sciences by involving a wide range of students, including those from underrepresented groups, in a materials chemistry research laboratory experience. Furthermore, a summer program for undergraduates allows the involvement of underrepresented minorities in research and teaches them about the chemistry of materials with the goal of recruiting them specifically into the University of South Carolina chemistry graduate program. Technical SummaryThe concept of materials discovery via crystal growth is applied to substantially increase the number of new fluoride and oxyfluoride material families to develop new functional materials. It is well known that complex fluoride materials are important for applications that rely on their optical properties, such as luminescence and scintillation, while the ability to obtain fluoride and oxyfluoride structures exhibiting magnetic frustration is of general interest for understanding spin-liquid and spin-ice behavior. The research project is centered around the development of new approaches to systematically synthesize and characterize new classes of fluoride and oxyfluoride materials and to study their optical and magnetic behavior. Specifically, the optimization of the crystal growth of new fluoride and oxyfluoride materials is carried out via three different synthetic routes (mild hydrothermal, supercritical hydrothermal, and flux crystal growth) to produce new magnetic and optical materials. Properties are controlled via the selection and incorporation of transition and lanthanide elements into the new fluoride and oxyfluoride structures, where those containing transition and lanthanide metals are used to study magnetic behavior and those containing lanthanides are used to study optical properties. As part of this research, numerous students are trained in the chemical sciences by involving a wide range of students, including those from underrepresented groups, in a materials chemistry research laboratory experience. Furthermore, a summer program for undergraduates allows the involvement of underrepresented minorities in research and teaches them about the chemistry of materials with the goal of recruiting them specifically into the University of South Carolina chemistry graduate program.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.