Si 2p and 2s resonant excitation and photoionization in SiF4.

Abstract

We present partial-cross-section results for Si 2p and valence photoionization of ${\mathrm{SiF}}_{4}$ for photon energies in the vicinity of the Si 2p and 2s thresholds. The continuum shape resonances decay only to the Si 2p main line, in accordance with one-electron theory predictions. The Si ${L}_{2}$,3VV Auger spectrum was also measured, and was found to agree with earlier work. We propose that variations in hole-interaction energies are important in assigning the Auger final states. For the Si 2p discrete excitations, spectra obtained on the ${\ensuremath{\sigma}}^{\mathrm{*}}$(${a}_{1}$) resonances compare well with previous qualitative results and the above-threshold Si ${L}_{2}$,3VV Auger spectrum. Our results help to quantify the relative enhancement of satellites and main lines, emphasizing the dominance of spectator decay. Spectra obtained at several higher-energy Si 2p and Si 2s excitations also generally support spectator decay as an important mode of relaxation for these discrete states. The overall assignment of the Si 2p and 2s discrete excitations to molecular-orbital and Rydberg transitions is discussed.