Shape‐resonant and many‐electron effects in the S 2p photoionization of SF6

The core‐level photoexcitation and photoionization of SF6 were studied in the vicinity of the resonances below and above the S 2p threshold. The decay channels of the S 2p→6a1g discrete excitation were characterized, with decay leading mostly to valence‐shell satellites. The S 2p continuum data show an oscillatory asymmetry parameter β(S 2p) near threshold that is virtually identical to β(Si 2p) in SiF4. It also resembles—but differs from—theoretical curves for β(S 2p) in atomic sulfur and in SF6. Data at the feature assigned as an eg shape resonance indicate strong multielectron properties for this state, because a resonance in the S 2p satellite is observed at the same photon energy as the main‐line resonance. We propose a unified model which generally includes configuration interaction both in the continuum‐state manifold and between discrete doubly excited states and the continua, to explain this unexpected satellite behavior. Finally, the S(L2,3VV) Auger electron asymmetry parameter shows no signific...

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