The elusive HNCOH+ ion characterized by a double‐collision experiment in the mass spectrometer

Abstract Previous studies have shown that the gas‐phase protonation of isocyanic acid, HNCO, exclusively yields the N‐protonated ion, the aminoformylium ion, H 2 NCO + , 1, which is thermodynamically the most stable [H 2 , C, N, O]isomer. In the present paper it is shown that the O‐protonated species, the elusive isoformylaminylium ion, HNCOH + , 2, can be generated by successive degradation of ionized N ‐methyl‐ O ‐methylcarbamate in a …