多金属氧酸盐TBA3[VW5O19]及TBA4[PVW11O40]的固体核磁共振研究

多金属氧酸盐（简称多酸，Polyoxometalates，POMs)是由处于d⁰电子构型的前过渡金属元素通过共边或共角缩聚而成的金属-氧簇类化合物．由于其具有丰富的分子结构和独特的物理化学性质，已经被广泛应用于功能材料、催化化学和药物化学等领域．其中钒取代的多酸阴离子具有很好的催化活性，特别是对烃类的氧化，它的活性主要受钒取代的数目和钒中心的阴离子环境这两个因素影响．该文利用固体核磁技术分析了一取代钒的两类典型结构中⁵¹V的局域结构和化学环境，以及有机阳离子对多酸阴离子结构的影响，特别是对⁵¹V的化学环境的影响，为研究多酸的催化活性和催化机理提供基本的结构信息．

Solid-State NMR Studies of TBA3[VW5O19] and TBA4[PVW11O40]

Polyoxometalates (POMs) are metal cluster compounds formed by transition metal atoms withd0 ord1 electron configuration via edge or corner polycondensation. Because of their unique molecular structures and physical/chemical properties, POMs have been widely used in functional materials, catalytic chemistry and medicinal chemistry etc. Vanadium-substituted POMs often have high catalytic activities for hydrocarbon oxidation, and such activities are mainly related to the number of vanadium atom and the electron environment these atoms are in. Solid-state NMR, as one of the most important methods to characterize solid acid materials, has been widely applied to study POMs. In this paper, butanyl cations and vanadium atoms in Lindqvist and Keggin oxopolytungstates were characterized by13C and51V solid state NMR spectroscopy to obtain information on the local environment these cations and vanadium centers are in. Such information is important for understanding the oxidation catalytic mechanism. It is concluded that51V solid state NMR spectroscopy can be a quick, convenient and nondestructive tool to study the local environment for vanadium atoms and the bulk morphologies of POMs.