CRYSTALLIZATION OF ZEOLITE ZSM-39 STUDIED BY C-13 AND SI-29 MAGIC-ANGLE-SPINNING NUCLEAR-MAGNETIC-RESONANCE SPECTROSCOPY

C-13 Cp MAS NMR, Si-29 MAS NMR and XRD have been used to study the cry stallization of zeolite ZSM-39 in the tetramethylethylenediamine (TMED A)-SiO2-H2O system. With the formation of the precursor from SiO2 spec ies surrounding TMEDA followed by nucleation, the C-13 chemical shift of the -C2H2- group moves progressively to higher field. This indicate s that one molecule of TMEDA is shared by two neighbours of the [5(12) 6(4)] cage and that the -C2H4- group of TMEDA interacts strongly with oxygen atoms located at the 6-ring window between the two cages.