Multinuclear NMR Studies of Structure & Dynamics in Complex Molecular Assemblies

吉娜湖作者声明：Robert L.威廉学院的沃尔德和玛丽是 在实验物理化学计划的支持下， 使用固态氘核核磁共振进行的持续研究 (NMR)光谱和扩展他们的工作使用氮-14和 碳-13核磁共振。 为了克服固有的低化学位移分辨率， 使用获得固态氘核NMR的标准方法，他们将 使用魔角旋转（MAS）实验来测量非常缓慢的运动 rates. 对于碳13，他们计划开发一种新的二维 方法，变角相关光谱（VACSY），并获得 通过将其与 自旋温度变化 对于氮-14，PI建议使用 具有随机激励的泛音光谱学作为 技术要求高的单量子氮-14 NMR直接检测 信号. 这些新技术将应用于尿素包合 化合物和树枝状聚酰胺胺。 分子动力学的新用途 用于解释复杂分子组装的NMR数据的模拟 也将被探索。 这项工作涉及新的多核核磁共振技术， 复杂分子组装中的结构和动力学。 一种改进 在分子水平上对有序和运动的理解将会增加 了解这些与宏观性质的关系。 最终，这种认知可能有助于指导新材料的设计 具有针对特定应用优化的性能。

Gina L. Hoatson and Robert L. Vold of the College of William and Mary are supported by the Experimental Physical Chemistry Program in their continuing studies using solid-state deuteron nuclear magnetic resonance (NMR) spectroscopy and the extension of their work using nitrogen-14 and carbon-13 NMR. To overcome the low chemical shift resolution inherent using standard methods for obtaining solid-state deuteron NMR, they will use magic angle spinning (MAS) experiments to measure very slow motional rates. For carbon-13, they plan to exploit a new two dimensional methodology, Variable Angle correlation SpectroscopY (VACSY), and obtain information about orientation dependent relaxation by combining this with spin temperature alternation. For nitrogen-14, the PIs propose to use overtone spectroscopy with stochastic excitation as an alternative to the technically demanding direct detection of single quantum nitrogen-14 NMR signals. These new techniques are to be applied to urea inclusion compounds and dendritic polyamidoamines. New uses of molecular dynamic simulations for interpreting NMR data for complex molecular assemblies will also be explored. This work involves novel multinuclear NMR techniques for determining structure and dynamics in complex molecular assemblies. An improved understanding of order and motion at the molecular level will increase knowledge of how these correlate with macroscopic properties. Eventually, this cognition may help direct the design of new materials with properties optimized for specific applications.