Photoelectron spectroscopy of some atmosperically important species and heavy metal compounds

Beeching, Levi James (2002) Photoelectron spectroscopy of some atmosperically important species and heavy metal compounds. University of Southampton, Doctoral Thesis.

Record type: Thesis (Doctoral)

Abstract

UV photoelectron spectroscopy studies of the reactive intermediates O₂(a¹Δ_g), OH and 0 haa been performed using using two different synchrotron sources. Autoionizing resonances have been observed and assigned to members of series of Rydberg states converging towards higher ionic limits. Vibrational resolution has been obtained for O₂(a¹Δ_g) and OH, and rotational resolution has been achieved for OH. Measurements of angular distributions of photoelectrons allowed insight into the photoionization dynamics to be obtained.

The UV photoelectron spectra of UBr₄ and ThBr₄ have been recorded in the gas-phase and complete ionic state assignment (including spin orbit splittings) has been achieved with the aid of relativistic density functional calculations. Matrix isolation infrared spectra have been recorded for UBr₄ and ThBr₄ and the results obtained are consistent with a tetrahedral geometry for these compounds.

2-Azidoethanol and 2-Azidoethylacetate have been studied by a variety of spectroscopic techniques, and their thermal decompositions have been studied by matrix isolation infrared spectroscopy and real-time ultraviolet photoelectron spectroscopy. This has allowed their mechanisms for decomposition to be proposed.

The HeI photoelectron spectrum of F₂O has been recorded with a better resolution than previously reported. New vibrational structure has been observed for the first time. The order and positions of the lowest four states of F₂O⁺ have been established by near state-of-the-art ab initio calculations and vibrational envelopes have been simulated employing both harmonic and anharmonic methods. Geometrical parameters were obtained for the F₂O⁺ (X̃;²B₁) and F₂O^-(²A₂) cationic states for the first time using the iterative Franck-Condon analysis (IFCA) procedure. Vibrational analysis of the second and third, heavily overlapped, photoelectron bands in the HeI photoelectron spectrum of F₂O was achieved based on a simulation of the experimental spectrum.