Degree Name

Master of Philosophy


School of Chemistry


�is thesis describes studies into gas-phase photochemistry of nitrogen containing heterocycles, together ion-trap mass spectrometers and tunable nanosecond laser light sources. �e �rst part of the thesis focuses on the oxidation reaction of the 5-dehydrouracil radical cation. �is radical cation is synthesised within the ion trap of a commercially available ion-trap mass spectrometer by irradiation of 5-iodouracil with 266nm photons. �e reaction of the radical cation species with oxygen is observed across 5 and 3000 ms, and second order rate constants are measured to be 7.3±0.2⇥10−11 cm3 molecule-1 s-1 for this gas-phase oxidation reaction. Computational studies of the reaction pathways are undertaken using G4-MP2-6x and products assigned as 4,5-dioxo-4,5-dihydropyrimidin- 1-ium formation as well as decarbonylation of the quinone species.



Unless otherwise indicated, the views expressed in this thesis are those of the author and do not necessarily represent the views of the University of Wollongong.