AVS 47th International Symposium
    Material Characterization Tuesday Sessions
       Session MC-TuP

Paper MC-TuP17
Satellite Structure of KLL Auger Spectra in Fluorides

Tuesday, October 3, 2000, 5:30 pm, Room Exhibit Hall C & D

Session: Poster Session
Presenter: L. Kövér, Institute of Nuclear Research of the HAS, Hungary
Authors: L. Kövér, Institute of Nuclear Research of the HAS, Hungary
M. Uda, Waseda University, Japan
I. Cserny, Institute of Nuclear Research of the HAS, Hungary
J. Tóth, Institute of Nuclear Research of the HAS, Hungary
K. Ogasawara, Kyoto University, Japan
H. Adachi, Kyoto University, Japan
Correspondent: Click to Email
Considerable chemical effects have been found on the satellite structures of the F KLL Auger spectra in fluorides recently,@footnote 1-3@ which could be important for surface chemical identification and could provide information on the origin and the atomic or molecular character of the particular Auger satellite lines. In the case of the alkali fluorides unassigned satellites were found and interpreted on the basis of a new concept,the resonant orbital rearrangement.@footnote 3@ In the present work we study the structure of the Auger satellites induced from rutile-type fluorides. F KLL Auger spectra were excited by Al K@alpha@ and Cu L@alpha@ X-rays from polycrystalline powder samples of MgF@sub 2@, ZnF@sub 2@, NiF@sub 2@ and CoF@sub 2@ and measured by a high luminosity electron spectrometer.@footnote 4@ Excitation by Cu L@alpha@ increased the peak to background ratio in the spectra significantly. Similarly to the alkali fluorides, a satellite has been found in the high kinetic energy part of the measured F KLL spectra. From the satellite intensities the fluorescence yield for the doubly ionized states in MgF@sub 2@ has been determined. An inverse proportionality has been found between the satellite/diagram X-ray and the corresponding Auger intensity ratios, while the latter ratios have been found to be proportional to the energy width of the new Auger satellites. These observations indicate the resonant nature of the Auger transition identified. For determining the energy difference between the molecular orbitals in resonance, Discrete Variational X@alpha@ cluster molecular orbital calculations have been performed. This work was supported by the projects OTKA T026514, MTA-JSPS 24/1998. @FootnoteText@ @footnote 1@ O. Benka and M. Uda, Phys. Rev. Letters, 56 (1986) 1667, @footnote 2@ H. Aksela, E. Kukk, S. Aksela, A. Kikas, E. Nommiste, A. Ausmees and M. Elango,Phys. Rev. B 49 (1994) 3116,@footnote 3@ M. Uda, T. Yamamoto and T. Takenaga, Adv. in Quant. Chem. 29 (1997) 389,@footnote 4@ L. Kövér, D. Varga, I. Cserny, J. Tóth and K. Tökési, Surf. Interface Anal. 19 (1992) 9.