Negative photoion spectroscopyof SF6 in the inner valence and S 2p energy regions

Abstract

Negative fragment ion formation from SF6 has been studiedusing synchrotron radiation within the energy range 20-205 eV.The fragment ions F-, F2-, S- and SF- have been observed. It is shown that shape resonance andunoccupied valence orbitals play an important role in negativeion formation after photoexcitation of inner valence and S 2pelectrons. The negative ion yields after photoexcitation of a S2p core electron show evidence of localization of the shaperesonance orbitals around the central S atom. The yields of F- and F2- in the outer valence and inner valence energy regions not only confirm that ion pair formationoccurs via predissociating Rydberg states but also demonstrate,for the first time, the importance of intravalence transitions.