NMR Studies of Molecular Motion in Constrained Environments

受限环境中分子运动的核磁共振研究

• 批准号: 9302557
• 负责人: Gina Hoatson
• 金额: $ 47.8万
• 依托单位: College of William and Mary
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 1993
• 资助国家: 美国
• 起止时间: 1993-06-01 至 1997-11-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9302557&HistoricalAwards=false
• 关键词: NMR; Studies; Molecular; Motion; Constrained

In this project in the Physical Chemistry Program of the Chemistry Division, Prof. Gina Hoatson of the College of William and Mary will engage in developing new techniques of pulsed nuclear magnetic resonance (NMR) spectroscopy in order to expand the accessible range of time scales over which the rates of molecular motion as well as the associated dynamical trajectories can be determined. These include methods of selective inversion, the determination of double quantum line shapes, methods of Hadamard excitation spectroscopy, which is a variant of stochastic NMR possessing considerable advantages over conventional pulsed NMR, and spectral density measurements on powders. Systems to be investigated in the course of this work include molecular crystals, inclusion compounds, and liquid crystals. %%% Nuclear Magnetic Resonance (NMR) spectroscopy is a powerful, ubiquitious method for the study of solids and liquids through the interaction of nuclear magnets of the constituent atoms with electromagnetic radiation. The absorption of this radiation by the nuclear magnets is not only characteristic of the specific chemical element but is also affected by the chemical environment. The atomic nuclei thus act as microscopic probes and yield site specific information about the structure and dynamics of the solid or liquid substance. Continual developments in theoretical and experimental techniques have resulted in vastly improved performance of the NMR method as a tool for basic studies of the properties of condensed matter and have greatly expanded its application to problems in physics, chemistry, materials science, biology, and medicine. In this project further developments are planned to enable the NMR method to deal with difficult or so far undoable problems and thereby extend the range of its applicability to practical problems.

在这个项目中的物理化学计划的 化学部，吉娜·霍特森教授的学院 威廉和玛丽将致力于开发新的技术， 脉冲核磁共振（NMR）光谱， 扩大可利用的时间尺度范围， 分子运动速率以及相关的动力学 可以确定轨迹。 这些方法包括： 选择性反转，双量子线的测定 形状，阿达玛激发光谱法，这是 随机核磁共振的一种变体，具有相当大的优点 与传统的脉冲核磁共振相比， 粉末。 在此过程中需要调查的系统 工作包括分子晶体，包合物， 液晶 %%% 核磁共振（NMR）光谱是一种强大的， 研究固体和液体的普遍方法， 组成原子的核磁体之间的相互作用 电磁辐射。 吸收这个 核磁铁的辐射不仅是 特定的化学元素，但也受到 化学环境。 因此，原子核充当 显微探针和产量现场具体信息 固体或液体物质的结构和动力学。 理论和实验的不断发展 技术已经大大提高了 核磁共振方法作为基础研究的工具， 凝聚态物质，并大大扩展了其应用， 物理、化学、材料科学、生物学和 药 在该项目中，计划进一步发展， 使核磁共振方法能够处理困难的或迄今无法做到的 问题，从而扩大其适用范围， 实际问题