日本ゼオライト学会　刊行物 Publication of Japan Zeolite Association

The recent researches on crystalline zincosilicate molecular sieves were reviewed. It is speculated that the research on molecular sieves with 3 membered rings (3MR) leads to synthesize molecularsieves that have low framework densities and multidimensional extra-large pores. The new zincosilicates with 3MRs such as VPI-7, RUB-17, and VPI-9 have been synthesized for a several years. It proves that crystalline zincosilicates tend to contain 3MRs in their framework structures. In the crystallization of VPI-8 that is a high silica zincosilicate, Zn plays an important role with a Li ion and a tetraethylammonium ion to build the novel pinwheel units peculiar to VPI-8. On the other hand, hypothetical structures with extra-large pores based on the novel pinwheel units were presented 2 years ago. It will be interesting to see if zincosilicate chemistry can be extended to synthesize extra-large pore materials.