Purchase of a Powder X-Ray Diffractometer

购买粉末X射线衍射仪

• 批准号: 0541812
• 负责人: Vartkess Apkarian
• 金额: $ 27.64万
• 依托单位: University of California-Irvine
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2006
• 资助国家: 美国
• 起止时间: 2006-02-15 至 2009-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0541812&HistoricalAwards=false
• 关键词: Purchase; Powder; Ray; Diffractometer

With support from the Chemistry Research Instrumentation and Facilities-Departmental Multiuser Instrument Acquisition (CRIF-MU) Program, the Department of Chemistry at the University of California in Irvine will acquire a powder X-ray diffractometer (powder XRD). This instrument will enable research in the following areas: a) expanding reduction chemistry via the f orbital metals; b) design of new polymeric materials at the interfaces with biology and catalysis; c) characterization of local order in protein nanocrystals and fibers; d) cadmium sulfide-selenide nanowires for fast photoconductive switches and chemical sensing; and e) polymer synthesis: the polyhomologation reaction. The X-ray diffractometer allows accurate and precise measurements of the full three dimensional structure of a molecule, including bond distances and angles, and it provides accurate information about the spatial arrangement of the molecule relative to the neighboring molecules. The synthesis of materials having an extended structure, such as polymers, inorganic solids, or gels, often yields a polycrystalline or phase-impure powder. Powder XRD is the most powerful tool available for the structural characterization of such products. Powder XRD pattern can elucidate the structure and relative abundance of the crystalline phases present, it can expose the existence of preferred crystalline orientation of a film of a material relative to a crystalline substrate surface, and the XRD linewidth can provide an estimate of the mean crystallite (or grain) diameter. In addition, the structure of extremely thin films (100 nm) of materials can be investigated by powder-XRD whereas such films cannot be probed by single-crystal XRD. These studies will have an impact in a number of areas, especially synthetic chemistry.

在化学研究仪器和设施部门多用户仪器获取(CRIF-MU)计划的支持下，加州大学欧文分校化学系将获得一台粉末X射线衍射仪(粉末X射线衍射仪)。该仪器将使以下领域的研究成为可能：a)通过f轨道金属扩大还原化学；b)在生物和催化界面上设计新的聚合物材料；c)蛋白质纳米晶和纤维中局部有序的表征；d)用于快速光导开关和化学传感的硫化镉-硒纳米线；以及e)聚合物合成：多同源反应。X射线衍射仪可以精确和精确地测量分子的全部三维结构，包括键的距离和角度，并提供关于分子相对于邻近分子的空间排列的准确信息。合成具有延伸结构的材料，如聚合物、无机固体或凝胶，通常会产生多晶或相不纯的粉末。粉末X射线衍射仪是表征这类产物结构的最有力的工具。粉末X-射线衍射谱可以解释存在的晶相的结构和相对丰度，它可以揭示材料薄膜相对于晶体衬底表面的择优结晶取向的存在，而X射线衍射线宽可以提供平均微晶(或颗粒)直径的估计。此外，用粉末X射线衍射法可以研究材料的超薄薄膜(100 Nm)的结构，而用单晶X射线衍射法不能研究这种薄膜的结构。这些研究将在许多领域产生影响，特别是合成化学。