Gas-to-cluster effects in S 2p-excited SF{sub 6}

Journal Article · Sun Apr 14 04:00:00 EDT 2013 · Journal of Chemical Physics

DOI:https://doi.org/10.1063/1.4798975· OSTI ID:22105474

Flesch, Roman; Serdaroglu, Ertugrul; Ruehl, Eckart ^[1]; Brykalova, Xenia O.; Kan, Elena I.; Klyushina, Ekaterina S.; Krivosenko, Yuri S.; Pavlychev, Andrey A. ^[2]

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1. Physikalische und Theoretische Chemie, Institut fuer Chemie und Biochemie, Freie Universitaet Berlin, Takustr. 3, 14195 Berlin (Germany)
2. Institute of Physics, St. Petersburg State University, St. Petersburg 198504 (Russian Federation)

High resolution X-ray spectroscopic studies on free SF{sub 6} molecules and SF{sub 6} clusters near the S 2p ionization thresholds are reported. Spectral changes occurring in clusters for the intense molecular-like S 2p{sub 1/2,3/2}{yields} 6a{sub 1g}-, 2t{sub 2g}-, and 4e{sub g}-resonances are examined in detail. Neither gas-to-cluster spectral shifts nor changes in peak shape are observed for the pre-edge 6a{sub 1g}-band. Significant changes in band shape and distinct gas-to-cluster shifts occur in the S 2p{sub 1/2,3/2}{yields} 2t{sub 2g}- and 4e{sub g}-transitions. These are found in the S 2p-ionization continua. The quasiatomic approach is used to assign the experimental results. It is shown that a convolution of asymmetric and symmetric contributions from Lorentzian and Gaussian line shapes allows us to model the spectral distribution of oscillator strength for the S 2p{sub 1/2,3/2}{yields} 2t{sub 2g}-, and 4e{sub g}-transitions. The asymmetry is due to trapping of the photoelectron within the finite size potential barrier. The Lorentzian contribution is found to be dominating in the line shape of the S 2p{yields} 2t{sub 2g}- and 4e{sub g}-bands. The spectroscopic parameters of the spin-orbit components of both the 2t{sub 2g}- and 4e{sub g}-bands are extracted and their gas-to-cluster changes are analyzed. The photoelectron trapping times in free and clustered SF{sub 6} molecules are determined. Specifically, it is shown that spectral changes in clusters reflected in core-to-valence-transitions are due to a superposition of the singly scattered photoelectron waves at the neighboring molecules with the primary and multiply scattered waves within the molecular cage.

• OSTI ID: 22105474
• Journal Information: Journal of Chemical Physics, Journal Name: Journal of Chemical Physics Journal Issue: 14 Vol. 138; ISSN JCPSA6; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ASYMMETRY
DISTRIBUTION
MOLECULAR CLUSTERS
MOLECULES
OSCILLATOR STRENGTHS
PEAKS
PHOTOELECTRON SPECTROSCOPY
PHOTOIONIZATION
PHOTON-MOLECULE COLLISIONS
SHAPE
SPECTRAL SHIFT
SPIN
SULFUR FLUORIDES
X RADIATION
X-RAY SPECTRA