A hydrated aluminophosphate with both 4.82 and 63 sheets in the 4-connected framework
A hydrated aluminophosphate with both 4.82 and 63 sheets in the 4-connected framework
复制标题
4-连接框架中具有 4.82 和 63 个片层的水合磷酸铝
作者：
J. Pluth;J. V. Smith
沸石型多孔硅铝酸盐作为离子交换剂、分子筛和催化剂在工业上已变得重要1,2。从拓扑上讲，氧四面体的四面体中心位于各个 4 连通三维网络的节点处。由交替的 AlO4 和 PO4 四面体组成的四连接多孔骨架 (AlPO4) 是新型合成分子筛家族的基础，由于它们缺乏沸石的强离子交换和催化性能，该分子筛可能在工业上变得重要。铝磷酸盐显示出广泛的晶体结构，因为铝可以与四个、五个或六个氧原子配位，其中一些可能属于羟基或水物种3-12。作为磷酸铝晶体化学系统研究的一部分，我们发现合成相H3（参考文献13）（AlPO4·1.5 H2O）的骨架包含AlO4四面体和AlO4(H2O)2八面体之间交替的PO4四面体。正如这里报道的，通过连接相邻的Al和P原子形成的4连接的三维网络是一种包含6.6.6和4.8.8的新型网络。通过上下链接连接的二维网络。三维网络中两种类型的二维网络的共存表明，在尝试发明与分子筛技术潜在相关的新网络时不应过于严格地采用简约原则。
Porous aluminosilicates of the zeolite type have become important industrially as ion-exchangers, molecular sieves and catalysts1,2. Topologically, the tetrahedral centres of the oxygen tetrahedra lie at the nodes of various 4-connected three-dimensional nets. Four-connected porous frameworks (AlPO4) composed of alternating AlO4and PO4tetrahedra are the basis of a new family of synthetic molecular sieves, which may become important industrially because they lack the strong ion-exchange and catalytic properties of the zeolites3. Aluminophosphates display a wide range of crystal structures because Al can be coordinated to either four, five or six oxygen atoms, some of which may belong to either hydroxyl or water species3–12. As part of a systematic study of the crystal chemistry of aluminophosphates, we have found that the framework of synthetic-phase H3 (ref. 13) (AlPO4· 1.5 H2O) contains PO4tetrahedra alternating between AlO4tetrahedra and AlO4(H2O)2octahedra. As reported here, the 4-connected three-dimensional net formed by linking adjacent Al and P atoms is a new type containing 6.6.6 and 4.8.8. two-dimensional nets joined by up–down linkages. This coexistence of two types of two-dimensional· nets in a three-dimensional net suggests that the principle of parsimony should not be adopted too strictly in attempts to invent new nets of potential relevance to molecular sieve technology.