Direct Observation of Cyclic Carbenium Ions and Their Role in the Catalytic Cycle of the Methanol‐to‐Olefin Reaction over Chabazite Zeolites

Carbenium ions in zeolites: Two important carbenium ions have been observed for the first time under working conditions of the methanol-to-olefins (MTO) reaction over chabazite zeolites using (13) C NMR spectroscopy. Their crucial roles in the MTO reaction cycles have been demonstrated by combining experiments and theoretical calculations.