Generalization of the duration-time concept for interpreting high-resolution resonant photoemission spectra
2004 (English)In: Physical Review A. Atomic, Molecular, and Optical Physics, ISSN 1050-2947, E-ISSN 1094-1622, Vol. 69, no 2, 022707- p.Article in journal (Refereed) Published
The duration-time concept, vastly successful for interpreting the frequency dependence of resonant radiative and nonradiative x-ray scattering spectra, is tested for fine-scale features that can be obtained with state of the art high-resolution spectroscopy. For that purpose resonant photoelectron (RPE) spectra of the first three outermost singly ionized valence states X (2)Sigma(g)(+), A (2)Pi(u), and B (2)Sigma(u)(+), are measured for selective excitations to different vibrational levels (up to n=13) of the N 1s-->pi(*) photoabsorption resonance in N-2 and for negative photon frequency detuning relative to the adiabatic 0-0 transition of this resonance. It is found that different parts of the RPE spectrum converge to the spectral profile of direct photoionization (fast scattering) for different detunings, and that the RPE profiles are asymmetrical as a function of frequency detuning. The observed asymmetry contradicts the picture based on the simplified notation of a common scattering duration time, but is shown to agree with the here elaborated concept of partial and mean duration times. Results of the measurements and the simulations show that the duration time of the scattering process varies for different final electronic and different final vibrational states. This owes to two physical reasons: one is the competition between the fast vertical and the slow resonant scattering channels and the other is the slowing down of the scattering process near the zeros of the real part of the scattering amplitude.
Place, publisher, year, edition, pages
2004. Vol. 69, no 2, 022707- p.
ray raman-scattering, core-excited states, vibrational structure, symmetry-breaking, dependent decay, auger-spectra, emission, excitation, molecules, hcl
IdentifiersURN: urn:nbn:se:kth:diva-23226DOI: 10.1103/PhysRevA.69.022707ISI: 000189386300066ScopusID: 2-s2.0-8744241084OAI: oai:DiVA.org:kth-23226DiVA: diva2:341924
QC 20100525 QC 201110312010-08-102010-08-102011-10-31Bibliographically approved