The Experts below are selected from a list of 165 Experts worldwide ranked by ideXlab platform
I V Hertel - One of the best experts on this subject based on the ideXlab platform.
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hydrogen bonding in liquid water probed by resonant Auger Electron spectroscopy
Journal of Chemical Physics, 2007Co-Authors: Bernd Winter, U Hergenhahn, Manfred Faubel, O Bjorneholm, I V HertelAbstract:We have measured resonant and off-resonant Auger-Electron spectra of liquid water. Continuumlike transitions near and above the O1s vertical ionization energy are identified by the characteristic normal Auger-Electron spectra. On the contrary, well-resolved spectator shifts of the main Auger-Electron peak are observed at the liquid-water O1s absorption main edge and near the absorption pre-edge. The shifts of 1.4 and 1.9 eV arise from the localized nature of the excitation. Excited-state localization/delocalization is also discussed for the analogous vacuum ultraviolet (VUV) transitions, and we point out the similarities between x-ray and VUV absorption spectra of liquid water.
Bernd Winter - One of the best experts on this subject based on the ideXlab platform.
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hydrogen bonding in liquid water probed by resonant Auger Electron spectroscopy
Journal of Chemical Physics, 2007Co-Authors: Bernd Winter, U Hergenhahn, Manfred Faubel, O Bjorneholm, I V HertelAbstract:We have measured resonant and off-resonant Auger-Electron spectra of liquid water. Continuumlike transitions near and above the O1s vertical ionization energy are identified by the characteristic normal Auger-Electron spectra. On the contrary, well-resolved spectator shifts of the main Auger-Electron peak are observed at the liquid-water O1s absorption main edge and near the absorption pre-edge. The shifts of 1.4 and 1.9 eV arise from the localized nature of the excitation. Excited-state localization/delocalization is also discussed for the analogous vacuum ultraviolet (VUV) transitions, and we point out the similarities between x-ray and VUV absorption spectra of liquid water.
John A. Venables - One of the best experts on this subject based on the ideXlab platform.
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Auger Electron spectroscopy and microscopy with probe‐size limited resolution
Applied Physics Letters, 1991Co-Authors: Gary G. Hembree, Jeffery Drucker, F. C. H. Luo, Mohan Krishnamurthy, John A. VenablesAbstract:High spatial resolution Auger Electron spectra and images have been obtained by optimizing secondary Electron collection efficiency in a scanning transmission Electron microscope (STEM). We describe an ultrahigh vacuum, 100 keV STEM which is capable of collecting Auger Electron spectra and images with edge resolutions of ≤5 nm. Typical spectra and images from the Ge/Si(100) and Ag/Si(100) film growth systems are presented and discussed. These images demonstrate high‐resolution elemental mapping which can be used in the study of surface processes on the nanometer scale.
James P Cryan - One of the best experts on this subject based on the ideXlab platform.
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molecular frame Auger Electron energy spectrum from n2
Journal of Physics B, 2012Co-Authors: James P Cryan, J M Glownia, Jakob Andreasson, A Belkacem, N Berrah, Cosmin I Blaga, Christoph Bostedt, John D BozekAbstract:Here we present the first angle-resolved, non-resonant (normal) Auger spectra for impulsively aligned nitrogen molecules. We have measured the angular pattern of Auger Electron emission following K-shell photoionization by 1.1 keV photons from the Linac Coherent Light Source (LCLS). Using strong-field-induced molecular alignment to make molecular frame measurements is equally effective for both repulsive and quasi-bound final states. The capability to resolve Auger emission angular distributions in the molecular frame of reference provides a new tool for spectral assignments in congested Auger Electron spectra that takes advantage of the symmetries of the final diction states. Based on our experimental results and theoretical predictions, we propose the assignment of the spectral features in the Auger Electron spectrum.
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Auger Electron angular distribution of double core hole states in the molecular reference frame
Physical Review Letters, 2010Co-Authors: James P Cryan, J M Glownia, Jakob Andreasson, A Belkacem, N Berrah, Cosmin I Blaga, Christoph Bostedt, John D Bozek, Christian Buth, L F DimauroAbstract:The Linac Coherent Light Source free Electron laser is a source of high brightness x rays, 2 × 10 11 photons in a ∼5 fs pulse, that can be focused to produce double core vacancies through rapid sequential ionization. This enables double core vacancy Auger Electron spectroscopy, an entirely new way to study femtosecond chemical dynamics with Auger Electrons that probe the local valence structure of molecules near a specific atomic core. Using 1.1 keV photons for sequential x-ray ionization of impulsively aligned molecular nitrogen, we observed a rich single-site double core vacancy Auger Electron spectrum near 413 eV, in good agreement with ab initio calculations, and we measured the corresponding Auger Electron angle dependence in the molecular frame.
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Auger Electron angular distribution of double core hole states in the molecular reference frame
Physical Review Letters, 2010Co-Authors: James P Cryan, J M Glownia, Jakob Andreasson, A Belkacem, N Berrah, Cosmin I Blaga, Christoph Bostedt, John D Bozek, Christian Buth, L F DimauroAbstract:The Linac Coherent Light Source free Electron laser is a source of high brightness x rays, $2\ifmmode\times\else\texttimes\fi{}{10}^{11}$ photons in a $\ensuremath{\sim}5\text{ }\text{ }\mathrm{fs}$ pulse, that can be focused to produce double core vacancies through rapid sequential ionization. This enables double core vacancy Auger Electron spectroscopy, an entirely new way to study femtosecond chemical dynamics with Auger Electrons that probe the local valence structure of molecules near a specific atomic core. Using 1.1 keV photons for sequential x-ray ionization of impulsively aligned molecular nitrogen, we observed a rich single-site double core vacancy Auger Electron spectrum near 413 eV, in good agreement with ab initio calculations, and we measured the corresponding Auger Electron angle dependence in the molecular frame.
O Bjorneholm - One of the best experts on this subject based on the ideXlab platform.
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hydrogen bonding in liquid water probed by resonant Auger Electron spectroscopy
Journal of Chemical Physics, 2007Co-Authors: Bernd Winter, U Hergenhahn, Manfred Faubel, O Bjorneholm, I V HertelAbstract:We have measured resonant and off-resonant Auger-Electron spectra of liquid water. Continuumlike transitions near and above the O1s vertical ionization energy are identified by the characteristic normal Auger-Electron spectra. On the contrary, well-resolved spectator shifts of the main Auger-Electron peak are observed at the liquid-water O1s absorption main edge and near the absorption pre-edge. The shifts of 1.4 and 1.9 eV arise from the localized nature of the excitation. Excited-state localization/delocalization is also discussed for the analogous vacuum ultraviolet (VUV) transitions, and we point out the similarities between x-ray and VUV absorption spectra of liquid water.