Triple resonance solid-state NMR for multi-nuclear studies

这里要求的设备套件将使我们的固态AV 500 NMR光谱仪上的三重共振核磁共振（NMR）光谱。 关键组件包括三重共振4 mm魔角旋转探头（1H/19 F，X，Y）和用于第三通道的500 W放大器，以及用于将第三通道并入现有光谱仪控制台的附带硬件。 这台新设备将满足我们集团内多个研究项目的需求，并显著扩大这台光谱仪的容量。 可充电锂聚合物电池在便携式电子产品中有许多用途，并有望在零排放汽车领域取得重大突破。 新材料的成功取决于它们可逆传输锂离子的能力。 最近受到广泛关注的一类阴极材料是过渡金属磷酸盐，其具有促进离子传输的开放骨架结构。 残余偶极耦合的测量是表征局部动力学的强有力的方法，在蛋白质NMR社区中是众所周知的，但在我们的小组中率先将其应用于固态离子导体。新的设备套件将使我们能够使用新的光谱手柄，即6Li-31 P偶极耦合来研究锂离子动力学。 用于燃料电池的聚合物电解质膜可以提供环境友好的能量，它依赖于能够传导质子的膜。许多有竞争力的候选聚合物是全氟材料。 这里要求的探针将有助于在24 kHz的MAS频率下实现出色的19 F NMR，足以消除感兴趣的光谱区域的边带。 新的探针将使我们能够通过直接测量19 F和19 F-13 C交叉极化增强光谱来表征Nafion及其众多类似物的主链动力学。 与正在设计新型氟化质子传导聚合物的合成团队的新合作将成为可能。

The suite of equipment requested here will enable triple resonance nuclear magnetic resonance (NMR) spectroscopy on our solid-state AV 500 NMR spectrometer.  The critical components include the triple resonance 4mm magic angle spinning probe (1H/19F, X, Y) and the 500W amplifier for a third channel, as well as the accompanying hardware for incorporating a third channel into the existing spectrometer console.  This new equipment will meet the needs of several research projects within our group, and significantly expand the capacity of this spectrometer.      Rechargeable lithium polymer batteries find many uses in portable electronics, and are poised to lead major breakthroughs in the area of zero emission vehicles.  The success of new materials is governed by their ability to reversibly transport lithium ions.  A class of cathode materials which have received much attention lately are the transition metal phosphates, which have open framework structures that facilitate ion transport.  The measurement of residual dipolar couplings is powerful method for characterizing local dynamics, well-known in the protein NMR community, but pioneered in our group in its application to solid-state ionic conductors. The new suite of equipment will allow us to investigate lithium ion dynamics using a new spectroscopic handle, namely the 6Li-31P dipolar coupling.      Polymer-electrolyte membranes for fuel cells, which can provide environmentally friendly energy, rely on membranes able to conduct protons. Many of the competitive polymer candidates are perfluorinated materials.  The probe requested here will facilitate excellent 19F NMR, at MAS frequencies of 24kHz, sufficient to eliminate sidebands from the spectral region of interest.  The new probe will allow us to characterize backbone dynamics in Nafion and its numerous analogues, by measuring both 19F directly, and 19F-13C cross polarization enhanced spectra.  New collaborations with synthetic groups who are designing novel fluorinated proton-conducting polymers will be enabled.