Acquisition of a multi-purpose powder diffractometer for the X-ray facility at ASU Chemistry for use in research and education

有了化学研究仪器和设施：多用户计划(CRIF：MU)颁发的这一奖项，亚利桑那州立大学化学系将为X射线设施购买一台多功能粉末衍射仪。该衍射仪将用于下列方面的研究和教育：(1)半导体金属氢化物和金属/半金属-氢相互作用及其对化学结构和物理性质的影响的基础研究，(2)二氧化碳矿物封存的机理，这对经济上可行的低压封存过程的发展是重要的，(3)地球-S上地幔和下地幔边界硅酸盐的复杂相关系和结构化学的研究，(4)矿物在生物膜、沉积物和土壤中金属痕量元素富集性和分布中的作用，(5)铁磁性金属结构-性质关系的合成，和(6)玻璃材料中的成核和生长事件，这对于全面了解玻璃的物理化学和制造具有特殊性质的陶瓷非常重要。X射线衍射仪可以准确和精确地测量分子的三维结构，包括键距离和角度，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、玻璃或凝胶，通常会产生多晶或相不纯的粉末。粉末X射线衍射仪是对这类产物进行结构表征的最有力的工具。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(称为织构)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。

With this award from the Chemistry Research Instrumentation and Facilities: Multi User program (CRIF:MU), the Department of Chemistry at Arizona State University will acquire a multi-purpose powder diffractometer for the X-ray facility. This diffractometer will be used for research and education in the study of (1) semiconductor metal hydrides and in fundamental studies of metal/semimetal-hydrogen interactions and their consequences to chemical structures and physical properties, (2) mechanisms of carbon dioxide mineral sequestration which are important for the development of economically viable low pressure sequestration processes, (3) the study of complicated phase relations and structural chemistry of silicates at the boundary between the Earth?s upper and lower mantle, (4) the role of minerals in the enrichment and distribution of metal trace elements in biofilms, sediments and soils, (5) the synthesis of structure-property relationships of ferromagnetic metals, and (6) nucleation and growth events in glass materials important for a general understanding of the physical chemistry of glasses and for manufacturing ceramics with special properties.The X-ray diffractometer allows accurate and precise measurements of the 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, glasses, or gels, often yields a polycrystalline or phase-impure powder. Powder X-ray diffraction (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 (called texture) 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.