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X-RAY ABSORPTION NEAR EDGE STRUCTURE
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Fig.
1. Zn
K-edge XANES measured on free and bound Zn atoms. Contains
information on the unoccupied valence
orbitals. |
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| Fig. 2. Atomic XANES can be completely described by pre-edge
resonances due to transitions from 1s initial state to Rydberg
final states
below 1s ionisation treshold and absorption edge (arctg) due to
transitions into continuum states above 1s ionisation treshold. |
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Fig. 3. In solid state multiple scattering of photoelectron on
neighbor atoms must be taken into account. The calculated spectrum
based
on muffin-tin approximations is obtained by FEFF8 program for cluster
of 180 atoms. Calculation time on 350 MHz PC Pentium II: 10 hours |
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| Fig. 4. Schematic view of photoelectron scattering on neighbor atoms, determining the EXAFS oscilations and the resonances in XANES. | |
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| Fig. 5. Atoms and diatomic molecules.Schematic potentials (bottom)
and K-shell spectra (top) |
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| Fig 6. Schematic view of inner shell photoeffect in bound atoms:
transitions to bound and continuum orbitals. |
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E-mail:iztok.arcon@p-ng.si Last change: 06-Jun-2006 |
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