Vacuum ultraviolet photodissociation and photoionization of selected organosulfur compounds

Abstract

<p>Using translational spectroscopy and photoionization techniques some organosulfur compounds have been studied in the vacuum ultraviolet spectral region. The photofragmentation technique has been used to obtain data from which bond energies, product quantum state distribution, and energy partitioning among photofragments has been calculated. The photofragmentation experiment also provides information on the secondary photodissociation of primary photofragments such as SSCH[subscript]3, SCH[subscript]3, and SH. Photoelectron-photoion coincidence (PEPICO) spectra have been measured in the wavelength region of 900-1475 A. The PEPICO measurements provide detailed information about the unimolecular decomposition dynamics of state or energy-selected CH[subscript]3SH[superscript]+ and CH[subscript]3SCH[subscript]3[superscript]+. The energetic information obtained in the photoionization and photodissociation experiments allows estimates of the ionization energies for some radicals. Finally, a new laser photolysis method has been developed to study free radicals. Intersecting a high repetition rate excimer laser beam with a pulsed molecular beam, a cold pseudocontinuous beam of free radicals can be generated. Combining photoionization with this technique S, CS, CH[subscript]3 and SCH[subscript]3, photoionization efficiency curves have been obtained.</p>