Rearrangement and predissociation processes in negative molecular ions of nitrobenzenes

The reactions of resonant electron capture by the molecules of benzene nitroderivatives has been studied in the gas phase. Some fragment negative ions were found to be unstable with respect to electron autodetachment. This circumstance has been used for the determination of their structure. In particular, it has been established that the low measured appearance energy of neutral component of M? H]^? ion beam is a result of isomerization of nitrobenzenes' molecular ion, leading to the 2‐nitrosophenol structure with the subsequent formation of the phenoxide anion in the autodetaching state. The effective yield curves of some types of fragment ions demonstrate fine vibrational structures, testifying the predissociation mechanism of ion formation. For all detected ions, the absolute cross sections of formation have been measured. Copyright © 2009 John Wiley & Sons, Ltd.