Discrimination between Protonation Isomers of Quinazoline by Ion Mobility and UV-Photodissociation Action Spectroscopy

• DOI: 10.1021/acs.jpclett.0c01009
• Publication Date: 2020-05-05T15:53:30Z
• Authors: Samuel J. P. Marlton; Benjamin I. McKinnon; Boris Ucur; James P. Bezzina; Stephen J. Blanksby; Adam J. Trevitt
• Keywords: Ion-mobility spectrometry

The influence of oriented electric fields on chemical reactivity and photochemistry is an area increasing interest. Within a molecule, different protonation sites offer the opportunity to control location charge thus orientation fields. New techniques are needed discriminate between isomers in order understand this effect. This investigation reports UV-photodissociation action spectroscopy two (protomers) 1,3-diazanaphthalene (quinazoline) arising from nitrogen at either 1- or 3-position. It shown that these protomers separable by field-asymmetric ion mobility spectrometry (FAIMS) with confirmation provided (PD) spectroscopy. Vibronic features UVPD spectra computational input allow assignment origin transitions S1 S5 states both protomers. These experiments also provide vital benchmarks for protomer-specific calculations examination isomer-resolved reaction kinetics thermodynamics.