【作者】 王金月；

【导师】 胡常伟；

【作者基本信息】 四川大学 ， 物理化学， 2006， 博士

【摘要】 多金属氧酸盐(POM),是一类由前过渡金属阳离子以氧阴离子为“桥”,通过自组装过程形成的低聚氧阴离子簇合物(cluster),是配位化学中一大类无机分子,其基本结构单元MOn是以金属M为中心,氧(S,F,Br或其它p-区的元素)为配位原子,常以配位数n = 6(也可以为4,5,或7配位)形成的八面体。除了金属M和氧O之外,在POM的结构之中还有一种被标为X的原子,经常处于由基本单元MOn组成的笼MxOy的中心,并以四或者六配位的形式与其它的原子相联接。根据结构中是否包含X,POM可以被分为两种类型:同多阴离子(IPA) [MnOy]p–和杂多阴离子(HPA) [XzMnOy]q– (z≤n)。由于杂多阴离子特殊的几何结构和电子结构,使得它们具有许多特性,比如同时兼具酸性和氧化还原性两种功能,甚至在某些溶剂中表现出“假液相”行为等。基于此,HPA被作为催化新材料广泛应用于均相和多相催化反应,以及木质纸浆的漂白处理过程中,另外在电化学,光化学甚至医药领域中也有比较广泛的用途。POM备受关注的原因主要是其结构和性能可以人为地从分子和原子水平上加以调变,比如改变它们的拓扑结构,或是其中心原子X以及组成其笼状结构的金属原子M等。尤其是二十世纪七十年代初,POM在更多还原

【Abstract】 Polyoxometalates (POM) are series of oligomeric aggregative clusters assembled mainly by the early transition metal ions with oxygen anions as linked bridges. They are one set of inorganic molecules in the vast field of coordination compounds, which characterized by the primary packing unit MOn in which a metallic center M surrounded by some oxygen atoms (seldomly by sulfur, fluorine, bromine atoms, and other p-block elements) with coordination number n = 6 (it can also be 4, 5 or 7, as well). Besides these two kinds of atoms, other atom, which are usually labeled as X and always 4-fold or 6-fold-coordinated, lie in the center of the closed shell of MxOy self-assembled by the MOn units. Depending on whether X is present, POMs can be divided into two types, the isopolyanions (IPA) [MnOy]p– and heteropolyanions (HPA) [XzMnOy]q– (z≤n). Because of the special topological and electronic structures, HPAs exhibit versatile properties including acid, redox, bifunctional and even“pseudo-liquid”characteristics, which make them widely applied as acid and oxidation catalysts, as well as new materials in the fields of homo-/heterogeneous catalytic and environmentally-friendly wood更多还原