“…3,4 However, since in the case of intramolecular proton migration, the same molecule acts as both the donor and acceptor species, there are limitations for experimental studies as methods must be able to discriminate between two or more isomers protonated from different sites (i.e., protomeric isomers, or ''protomers''). To this end, spectroscopic and spectrometric techniques such as photodissociation spectroscopy, 5 IR multiphoton dissociation, 6 ion mobility-mass spectrometry (IM-MS), 7 or combination of them 8 have been applied in recent years for experimental discrimination and characterisation of protomers in the gas phase. Furthermore, computational methods are generally used independently or alongside these experimental techniques for investigation of intramolecular proton transfer.…”