Core-level excitation in argon clusters

✍ Scribed by E. Rühl; H.W. Jochims; C. Schmale; E. Biller; A.P. Hitchcock; H. Baumgärtel

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 618 KB
• Volume: 178
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(91)87020-c

✦ Synopsis

Argon clusters prepared in a supersonic-jet expansion are photoionized with monochromatized synchrotron radiation in the L,/b regime (240-280 eV). The cluster cations and their fragments are mass selected in a quadrupole mass spectrometer. The photoionization-efficiency curves of small cluster ions already show similar features which are known from X-ray absorption of solid argon. These solid-like features become more dominant when the cluster-size distribution of the neutral precursors is increased. The spectra are analysed in terms of near-edge features (NEXAFS) and extended fine structure (EXAFS). The NEXAFS regime shows cluster-specific features which are different compared to the atom and the solid. In the energy regime above 260 eV. EXAFS-like structures have been identified. Possible fragmentation mechanisms for core-level-excited argon clusters are discussed.