Molecular mechanics calculations on the N,N-diethyl-3,5-dimethylpiperidinium ions in MEL and MFI

Abstract The interaction of N,N -diethyl-3,5-dimethylpiperidinium (DDP) ions with the all-silica zeolite frameworks of type MEL and MFI was studied by means of molecular mechanics calculations. It is shown that both cis - and trans -DDP stabilize MEL better than MFI. DDP fits in both types of intersections of MEL. In contrast to tetrabutylammonium ions DDP ions in adjacent intersections do not hinder each other. MEL can therefore accommodate four DDP ions per unit cell. This might be the reason why pure MEL can be synthesized when DDP is used as templating agent.