Inner- and valence-shell excitation of SF4 studied by photoabsorption and electron energy loss spectroscopy

The S 1s photoabsorption spectrum of SF4 recorded with synchrotron radiation is reported along with the electron energy loss spectrum of SF4 in the regions of S 2p, S 2s and F 1s excitation recorded under dipole dominated conditions. The electron energy loss spectrum of SF4 in the region of valence electron excitation is also reported. All of these spectra are interpreted in terms of a common manifold of upper levels which includes valence levels whose term values reflect the different axial and equatorial SF bond lengths in this molecule. The spectra are good examples of the effects of potential barriers on electronic excitation spectra.