Photodissociation Dynamics of Halogen Oxide Species

Abstract

The focus of this dissertation is the study of the photodissociation dynamics of halogen oxide species (XO, X = Cl, Br, I). These radical species are known to be important in stratospheric and tropospheric ozone depletion cycles. They are also useful benchmark systems for the comparison to current theoretical methods where they provide insight into the dynamics occurring beyond the Franck-Condon region. These systems are studied using velocity map ion imaging, a technique that measures velocity and angular information simultaneously. Photofragment species are state-selectively ionized for detection using 2+1 REMPI (Resonance Enhanced Multi-Photon Ionization). The instrumentation employs a molecular beam of the XO radicals formed using pyrolitic and photolytic methods. The current work involves the measurement of fundamental physical constants of the XO species. The bond dissociation energy of IO is measured. Vibrational level dependent correlated final state branching ratios of the predissociation of the A(^2 II_3/2) state of ClO and BrO are reported, and comparison to theoretical methods is discussed.