Studies of some reactive intermediates in the gas-phase by ultra-violet photoelectron spectroscopy

This thesis describes the study of a number of small molecules by photoelectron spectroscopy. These molecules were highly reactive and were prepared in situ using a photoelectron spectrometer built specifically for such experimental studies. This spectrometer is described in Chapter 2. Chapter 3 describes the theoretical methods used in this thesis to aid spectral assignment. The short-lived molecules studied are of interest both in combustion and interstellar chemistry. The two molecules for which the photoelectron spectra are described in Chapters 4 and 5, NC1 and HCO respectively, are both of interest in interstellar chemistry and HCO is a well known intermediate in combustion processes. Chapter 6 studies the reaction of atomic fluorine with hydroxylamine. The photoelectron bands observed in the resulting spectra have been assigned to the primary reaction product, the NH2O radical, and the secondary reaction product, the HNO molecule. Chapter 8 is a study of the gas-phase reaction of atomic and molecular fluorine with CH3SH, CH3SCH3 and CH3SSCH3. Where possible the reaction products have been identified and their associated photoelectron bands characterized. Chapter 7 examines the photoelectron spectrum of the phenyl radical produced from the reaction of fluorine atoms with benzene. The reaction of deuteriated benzene with atomic fluorine yielded an additional photoelectron band in the spectrum which has been assigned to the 1-fluorocyclohexadienyl radical. This band was not observed in the reaction of atomic fluorine with benzene. Finally, Chapter 9 presents the results of some preliminary studies of some chlorosilanes and the primary products of the reaction of acetaldehyde with fluorine atoms. (D82619)