THEORETICAL ESTIMATION OF ORDERED METAL SPECIES IN ZEOLITE PORES

The combination of computational techniques such as computer graphics (CG), molecular dynamics (MD) and quantum chemistry (QC) methods are d emonstrated to be effective for investigating the dynamics and formati on of ordered metal species in zeolite pores. The behavior of metal at oms in all-silicon mordenite and ion-exchanged mordenite with Si/Al = 5 have been studied. The MD calculations on mordenite containing many metals in its pore confirm that the zeolite framework is rigid enough to hold the metal particles. In addition to the cohesive force, the co ncentration, the size of metal particles and size matching to the pore structure of zeolite also influence the ordering and the stability of metals. It is suggested from MD calculations and confirmed by QC calc ulations that the exchanged cations stabilize the ordering of metal pa rticles in the zeolite pore.