RUI: CAS: Solvent-Free Synthesis of Transition Metal Halide Clusters

在化学系化学合成项目的支持下，Otterbein大学的Dean约翰斯顿教授将开发新的合成路线，以取代过渡金属卤化物簇合物材料，这些材料在生物成像，液晶和光学器件，催化，氧传感和X射线造影剂方面具有潜在的未来应用。这类簇是强磷光的，并且具有独特的电化学性质，使得簇有可能用于广泛的应用。中心簇核非常稳定，使其成为创建新化学结构的理想构建块，这些结构将簇单元连接起来形成链或三维网络。重要的是要注意，目前用于制备改性簇的基于溶液的方法受到产物的反应性和溶解性的严重限制，从而限制了可以生成和分离的材料的类型。该项目旨在克服与当前合成技术相关的障碍。研究团队将利用金属簇盐的热加热和机械研磨来制备具有光学器件和传感潜在应用的新型材料。Otterbein大学的本科生将通过整合到无机化学实验室的夏季研究经验和活动参与该项目，获得独立研究以及无机材料合成和表征的宝贵经验。这些研究经验将补充红衣主教科学学者计划的活动，这是一项由NSF支持的学术，课外和非学术活动计划，旨在提高科学，技术，工程，和数学（STEM）。本研究项目旨在制备金属簇合物，这些金属簇合物可用作新分子和材料的构建块，允许精确控制簇材料的连接性和维度。大于95%的所有已知金属卤化物簇衍生物是均配的，说明了使用基于溶液的合成路线进行选择性配体取代的困难。约翰斯顿研究小组将制备金属卤化物簇合物盐，其中阳离子被选择与阴离子簇合物反应，利用电荷平衡和阳离子的性质来控制反应的化学计量。反应将在不存在溶剂的情况下通过热或机械化学手段引发，从而避免溶剂干扰或溶解度问题的复杂性。将使用热重分析、原位拉曼光谱、粉末和单晶X射线衍射方法分析反应和产物。该研究成果有望为无机团簇化学领域的研究人员提供合成工具和途径，以制备基于团簇的新材料。该奖项反映了NSF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。

With the support of the Chemical Synthesis program in the Division of Chemistry, Professor Dean Johnston of Otterbein University will develop new synthetic routes to substituted transition metal halide cluster materials that have potential future applications in bioimaging, liquid crystal and optical devices, catalysis, oxygen sensing, and as X-ray contrast agents. This family of clusters is strongly phosphorescent and has unique electrochemical properties, making the clusters potentially useful for a wide range of applications. The central cluster core is very stable, making it an ideal building block for the creation of new chemical constructs that link cluster units to form chains or three-dimensional networks. It is important to note that current solution-based methods for preparing modified clusters are severely limited by the reactivity and solubility of the products, restricting the types of materials that can be generated and isolated. This project seeks to overcome obstacles associated with current synthetic techniques. The research team will use thermal heating and mechanical grinding of metal cluster salts to prepare novel materials with potential applications for optical devices and sensing. Undergraduate students at Otterbein University will engage with this project through summer research experiences and activities integrated into the Inorganic Chemistry laboratory, gaining valuable experience in independent research and the synthesis and characterization of inorganic materials. These research experiences will complement the activities of the Cardinal Science Scholars Program, an NSF-supported program of academic, co-curricular, and non-academic activities demonstrated to increase retention and graduation in science, technology, engineering, and mathematics (STEM).This research project is directed toward the preparation of metal cluster synthons that are intended to serve as building blocks for new molecules and materials and to allow for precise control over connectivity and dimensionality of cluster materials. Greater than ninety-five percent of all known metal halide cluster derivatives are homoleptic, illustrating the difficulty in selective ligand substitution using solution-based synthetic routes. The Johnston research team will prepare metal halide cluster salts where the cation is selected to react with the anionic cluster, using charge balance and the properties of the cation to control the stoichiometry of the reaction. Reactions will be initiated by thermal or mechanochemical means in the absence of solvent, thereby avoiding complications from solvent interference or solubility issues. The reactions and products will be analyzed using thermogravimetric analysis, in-situ Raman spectroscopy, and powder and single-crystal X-ray diffraction methods. The results of this research are expected to provide researchers in the field of inorganic cluster chemistry with synthetic tools and pathways to prepare new cluster-based materials.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.