Where zeolites and oxides merge: semi-condensed tetrahedral frameworks

The synthesis of new inorganic materials constructed with extended lattices has taken place mainly in two areas, complex oxides and porous framework s tructures. In the former case the drive has been towards controlling electr onic and magnetic properties while in the latter domain porosity and the ab ility to enclathrate small organic or inorganic units has been paramount. S emi-condensed framework materials, whose compositions and structures place them at the borderline of these two classes, are described in this article, such compound types include the sodalite, cancrinite, analcime, zeloites A BW and JBW and scapolite structures. In each case recent chemistry and deve lopments are described particularly with respect to advances made at The Un iversity of Southampton. The potential for merging the properties and struc tures of these two classes of compounds are also discussed.