USE OF ELECTRON-MICROSCOPY AND MICRODIFFRACTION FOR ZEOLITE FRAMEWORKCOMPARISON

Recent successful zeolite structure determination based on electron di ffraction and image analysis data shows interesting prospects to chara cterize zeolitic frameworks provided the crystals are thin enough to p roduce useful crystallographic phases from image analysis. Zeolite SSZ -25 and porosil ITQ-1 structures were compared to reveal if they are i somorphous to MCM-22 zeolite. By using electron microdiffraction inten sity data in the [0001] axis and phases extracted from HREM images tak en at different defocus conditions, the resulting projected [0001] pot ential maps are found to be very similar for both structures and close to that of the MCM-22 zeolite.