Selective resonant photoionization processes near the Si 2pedge of tetramethylsilane

Photoelectron spectroscopy and photoion-photoion coincidence technique are combined for the first time to show, in a molecule, the selectivity of electronic decay channels of resonances near a core edge. Tetramethylsilane is studied near the ${\mathrm{L}}_{\mathrm{I}\mathrm{I},\mathrm{I}\mathrm{I}\mathrm{I}}$ level of silicon, by use of monochromatized synchrotron radiation in the 100–120-eV range. Autoionization and simple and double-resonant Auger processes explain the formation of one-hole and multiple-hole excited configurations of the final ionic states.