title: Photoabsorption and S 2p photoionization of the SF6 molecule: resonances in the excitation energy range of 200-280 eV.
abstract: Photoabsorption and S 2p photoionization of the SF(6) molecule have been studied experimentally and theoretically in the excitation energy range up to 100 eV above the S 2p ionization potentials. In addition to the well-known 2t(2g) and 4e(g) shape resonances, the spin-orbit-resolved S 2p photoionization cross sections display two weak resonances between 200 and 210 eV, a wide resonance around 217 eV, a Fano-type resonance around 240 eV, and a second wide resonance around 260 eV. Calculations based on time-dependent density functional theory allow us to assign the 217-eV and 260-eV features to the shape resonances in S 2p photoionization. The Fano resonance is caused by the interference between the direct S 2p photoionization channel and the resonant channel that results from the participator decay of the S 2s(-1)6t(1u) excited state. The weak resonances below 210-eV photon energy, not predicted by theory, are tentatively suggested to originate from the coupling between S 2p shake-up photoionization and S 2p single-hole photoionization. The experimental and calculated angular anisotropy parameters for S 2p photoionization are in good agreement.
authors.affiliation: Dipartimento di Scienze Chimiche, Università di Trieste, Trieste, Italy. stener@univ.trieste.it
authors.forename: M
authors.initials: M
authors.lastname: Stener
authors.forename: P
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authors.lastname: Bolognesi
authors.forename: M
authors.initials: M
authors.lastname: Coreno
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authors.initials: P
authors.lastname: O'Keeffe
authors.forename: V
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authors.lastname: Feyer
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authors.lastname: Fronzoni
authors.forename: P
authors.initials: P
authors.lastname: Decleva
authors.forename: L
authors.initials: L
authors.lastname: Avaldi
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authors.initials: A
authors.lastname: Kivimäki