MRI: Acquisition of a single crystal x-ray diffractometer at UC Merced

MRI：在加州大学默塞德分校购买单晶 X 射线衍射仪

• 批准号: 2216471
• 负责人: Michael Findlater
• 金额: $ 28万
• 依托单位: University of California - Merced
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2025-08-31
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2216471&HistoricalAwards=false
• 关键词: MRI; Acquisition; single; crystal; ray

This award is jointly supported by the Major Research Instrumentation and the Chemistry Research Instrumentation Programs. The University of California - Merced is acquiring a dual-source single crystal diffractometer equipped with Cu and Mo microfocus X-ray sources, Professor Michael Findlater and colleagues Rebeca Arevalo, Mehmet Baykara, Jennifer Lu, Yanbao Ma. In general, an X-ray diffractometer allows accurate and precise measurements of the full three-dimensional structure of a molecule, including bond distances and angles, and provides accurate information about the spatial arrangement of a molecule relative to neighboring molecules. The studies described here impact many areas, including organic and inorganic chemistry, quantum materials, materials chemistry, biochemistry, and catalysis. This instrument is an integral part of teaching as well as research and research training of undergraduate and graduate students in chemistry and biochemistry at this institution. The facility serves as a regional XRD resource benefitting students and faculty from primarily undergraduate institutions within the Central Valley region of California with impacts through active collaborations with researchers California Polytechnic State University, CSU Sate East Bay, CSU State Stanislaus, and Western Oregon University.The award is aimed at enhancing research and education at all levels. Research enabled by the instrument is focused on the synthesis, isolation, characterization, and reactivity of molecular compounds with 1st-row metal elements which exhibit such redox behaviors. The identification of novel structure and bonding has long been a central tenet of molecular inorganic / organometallic chemistry, and SCXRD is an essential characterization tool. More efficient access to crystallographic data helps streamline the development of structural analogues and guide the design of future structural modifications based on rotamer assessment. This is needed of the development of transnitrosylation reactions from novel nitrosoreagents. X-ray crystallography has become much more than a tool for structure determination - it is a technique that allows the exploration of the conformational landscapes of complex molecules in atomic detail. The instrument helps develop new computational tools that enable "multi-conformer" or "ensemble" modeling of crystallographic data, revealing hidden alternative conformations of macromolecules, which is often critical for understanding their functions. Researchers are working on single crystal selection and manipulation for the SCXRD. For material and chemical applications, dry crystal specimen is commonly used in the SCXRD. For biochemical and biological applications, the specimen may stay in aqueous solutions during the SC-XRD measurements. Depending on different applications, either acoustic or optical tweezers are utilized. Water electrolysis is a viable option towards hydrogen production that facilitates the transition into a decarbonized economy. The structures and purity of catalytic materials are Confirmed by XRD results. The discovery that the structure of 2D materials used as solid lubricants has a profound effect on their frictional properties. In particular, MoS2 doped with Re ions exhibits an anomalous, i.e. inverse dependence of friction on number of layers in violation of the seemingly universal trait that friction decreases with increasing number of layers in 2D materials. Structure determination using the instrument is of prime importance for friction research. SCXRD is an essential characterization tool for identifying new phases and structures of quantum materials. SCXRD is used to identify the crystal structure of the synthesized quantum materials and study the evolution of their lattice and phase upon the introduction of heterogeneities. Metal halide perovskites (MHPs) have had a meteoric rise in the last decade as active materials in high-efficiency single junction solar cells. The first and most critical step following synthesis of these materials is SCXRD to ascertain lattice constants and crystal orientation of the MHPS. Without this characterization, any measurement done on these samples have retain considerable uncertainty and do not allow to establish the correlations between composition and optoelectronic behavior. Metal organic frameworks (MOFs), consisting of metal ions and their interlinking organic ligands, can be formed into a highly crystalline porous structure with excellent tunability in both morphology and functionality, which provides an attractive platform to explore unprecedented catalytic activity and selectivity. Characterization of these materials with SCXRD allow understanding where the catalytically active sites are located and how the electrocatalysis occurred on those sites.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.

该奖项由主要研究仪器和化学研究仪器项目联合支持。加州大学默塞德分校的Michael Findlater教授和他的同事Rebeca Arevalo， Mehmet Baykara, Jennifer Lu， Yanbao Ma正在获得一个配备Cu和Mo微聚焦x射线源的双源单晶衍射仪。一般来说，x射线衍射仪可以精确测量分子的完整三维结构，包括键距和角度，并提供有关分子相对于邻近分子的空间排列的准确信息。这里描述的研究影响了许多领域，包括有机和无机化学、量子材料、材料化学、生物化学和催化。该仪器是该机构化学和生物化学本科生和研究生的教学、研究和研究训练的一个组成部分。该设施作为区域XRD资源，通过与加州州立理工大学、CSU州立东湾分校、CSU州立斯坦尼斯劳斯分校和西俄勒冈大学的研究人员的积极合作，使加州中央山谷地区主要本科院校的学生和教师受益。该奖项旨在加强各级的研究和教育。该仪器的研究主要集中在具有第一排金属元素的分子化合物的合成、分离、表征和反应性上，这些分子化合物具有氧化还原行为。新结构和键的鉴定一直是分子无机/有机金属化学的核心原则，而SCXRD是必不可少的表征工具。更有效地获取晶体学数据有助于简化结构类似物的开发，并指导基于转子评估的未来结构修改设计。这是发展新型亚硝基试剂的转亚硝基化反应所必需的。x射线晶体学已经不仅仅是一种确定结构的工具，它是一种可以探索复杂分子在原子细节上的构象的技术。该仪器有助于开发新的计算工具，实现晶体学数据的“多构象”或“集成”建模，揭示隐藏的大分子替代构象，这对于理解其功能通常至关重要。研究人员正在研究SCXRD的单晶选择和操作。对于材料和化学应用，SCXRD中通常使用干晶试样。对于生物化学和生物学的应用，在SC-XRD测量期间，样品可能停留在水溶液中。根据不同的应用，使用声学或光学镊子。水电解是一种可行的制氢选择，有助于向脱碳经济过渡。XRD结果证实了催化材料的结构和纯度。作为固体润滑剂的二维材料的结构对其摩擦性能有深远的影响。特别是，掺杂了Re离子的MoS2表现出一种反常的现象，即摩擦与层数呈反比关系，这违反了二维材料中摩擦随层数增加而减小的看似普遍的特性。该仪器的结构测定对摩擦研究至关重要。SCXRD是识别量子材料新相和新结构的重要表征工具。利用SCXRD对合成的量子材料的晶体结构进行鉴定，研究了引入非均质性后其晶格和相的演变。金属卤化物钙钛矿（MHPs）在过去十年中作为高效单结太阳能电池的活性材料迅速崛起。合成这些材料后的第一步也是最关键的一步是SCXRD，以确定MHPS的晶格常数和晶体取向。如果没有这种表征，对这些样品进行的任何测量都保留了相当大的不确定性，并且不允许建立成分与光电行为之间的相关性。金属有机骨架（MOFs）由金属离子及其相互连接的有机配体组成，可以形成高度结晶的多孔结构，具有良好的形态和功能可调性，为探索前所未有的催化活性和选择性提供了一个有吸引力的平台。利用SCXRD对这些材料进行表征，可以了解催化活性位点的位置以及电催化是如何在这些位点上发生的。该奖项反映了美国国家科学基金会的法定使命，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。