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Travnikova O, Patanen M, Söderström J, Lindblad A, Kas JJ, Vila FD, Céolin D, Marchenko T, Goldsztejn G, Guillemin R, Journel L, Carroll TX, Børve KJ, Decleva P, Rehr JJ, Mårtensson N, Simon M, Svensson S, Sæthre LJ. Energy-Dependent Relative Cross Sections in Carbon 1s Photoionization: Separation of Direct Shake and Inelastic Scattering Effects in Single Molecules. J Phys Chem A 2019; 123:7619-7636. [PMID: 31386367 DOI: 10.1021/acs.jpca.9b05063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We demonstrate that the possibility of monitoring relative photoionization cross sections over a large photon energy range allows us to study and disentangle shake processes and intramolecular inelastic scattering effects. In this gas-phase study, relative intensities of the carbon 1s photoelectron lines from chemically inequivalent carbon atoms in the same molecule have been measured as a function of the incident photon energy in the range of 300-6000 eV. We present relative cross sections for the chemically shifted carbon 1s lines in the photoelectron spectra of ethyl trifluoroacetate (the "ESCA" molecule). The results are compared with those of methyl trifluoroacetate and S-ethyl trifluorothioacetate as well as a series of chloro-substituted ethanes and 2-butyne. In the soft X-ray energy range, the cross sections show an extended X-ray absorption fine structure type of wiggles, as was previously observed for a series of chloroethanes. The oscillations are damped in the hard X-ray energy range, but deviations of cross-section ratios from stoichiometry persist, even at high energies. The current findings are supported by theoretical calculations based on a multiple scattering model. The use of soft and tender X-rays provides a more complete picture of the dominant processes accompanying photoionization. Such processes reduce the main photoelectron line intensities by 20-60%. Using both energy ranges enabled us to discern the process of intramolecular inelastic scattering of the outgoing electron, whose significance is otherwise difficult to assess for isolated molecules. This effect relates to the notion of the inelastic mean free path commonly used in photoemission studies of clusters and condensed matter.
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Affiliation(s)
- Oksana Travnikova
- LCPMR, CNRS, Sorbonne Université, UMR7614 Paris, France.,Synchrotron Soleil, L'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette, France
| | - Minna Patanen
- Nano and Molecular Systems Research Unit, Faculty of Science, University of Oulu, P.O. Box 3000, 90014 Oulu, Finland
| | - Johan Söderström
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, 75120 Uppsala, Sweden
| | | | - Joshua J Kas
- Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195-1560, United States
| | - Fernando D Vila
- Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195-1560, United States
| | - Denis Céolin
- Synchrotron Soleil, L'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette, France
| | - Tatiana Marchenko
- LCPMR, CNRS, Sorbonne Université, UMR7614 Paris, France.,Synchrotron Soleil, L'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette, France
| | | | - Renaud Guillemin
- LCPMR, CNRS, Sorbonne Université, UMR7614 Paris, France.,Synchrotron Soleil, L'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette, France
| | - Loïc Journel
- LCPMR, CNRS, Sorbonne Université, UMR7614 Paris, France.,Synchrotron Soleil, L'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette, France
| | - Thomas X Carroll
- Division of Natural Sciences, Keuka College, Keuka Park, New York 14478, United States
| | - Knut J Børve
- Department of Chemistry, University of Bergen, Allégaten 41, NO-5007 Bergen, Norway
| | - Piero Decleva
- Dipartimento di Scienze Chimiche e Farmaceutiche, Universitá di Trieste and IOM-CNR, 34127 Trieste, Italy
| | - John J Rehr
- Department of Physics, University of Washington, Box 351560, Seattle, Washington 98195-1560, United States
| | - Nils Mårtensson
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, 75120 Uppsala, Sweden
| | - Marc Simon
- LCPMR, CNRS, Sorbonne Université, UMR7614 Paris, France.,Synchrotron Soleil, L'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette, France
| | - Svante Svensson
- Department of Physics and Astronomy, Uppsala University, P.O. Box 516, 75120 Uppsala, Sweden
| | - Leif J Sæthre
- Department of Chemistry, University of Bergen, Allégaten 41, NO-5007 Bergen, Norway
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Meyer M, Grum-Grzhimailo AN, Cubaynes D, Felfli Z, Heinecke E, Manson ST, Zimmermann P. Magnetic dichroism in K-shell photoemission from laser excited Li atoms. PHYSICAL REVIEW LETTERS 2011; 107:213001. [PMID: 22181876 DOI: 10.1103/physrevlett.107.213001] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/15/2011] [Indexed: 05/31/2023]
Abstract
Magnetic dichroism in the angular distribution has been demonstrated for single-electron photoemission from inner ns(2) subshells of gaseous atomic targets using the example of K-shell photoionization of polarized Li atoms laser prepared in the 1s(2)2p (2)P(3/2) excited state. The effect is pronounced for the conjugate shakeup and conjugate shakedown photoelectron lines, and less important, though observable, for the main and direct shakeup lines. The phenomenon is caused by configuration interaction in the final continuum state and is quantitatively described by the close-coupling R-matrix calculations.
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Affiliation(s)
- M Meyer
- European XFEL GmbH, Albert-Einstein-Ring, Hamburg, Germany
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Zhu G, Schuricke M, Steinmann J, Albrecht J, Ullrich J, Ben-Itzhak I, Zouros TJM, Colgan J, Pindzola MS, Dorn A. Controlling two-electron threshold dynamics in double photoionization of lithium by initial-state preparation. PHYSICAL REVIEW LETTERS 2009; 103:103008. [PMID: 19792307 DOI: 10.1103/physrevlett.103.103008] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2009] [Indexed: 05/28/2023]
Abstract
Double photoionization (DPI) and ionization-excitation (IE) of Li(2s) and Li(2p), state-prepared and aligned in a magneto-optical trap, were explored in a reaction microscope at the free-electron laser in Hamburg (FLASH). From 6 to 12 eV above threshold (homega = 85, 91 eV), total as well as differential DPI cross sections were observed to critically depend on the initial state and, in particular, on the alignment of the 2p orbital with respect to the VUV-light polarization, whereas no effect is seen for IE. The alignment sensitivity is traced back to dynamical electron correlation at threshold.
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Affiliation(s)
- G Zhu
- Max-Planck-Institut für Kernphysik, Saupfercheckweg 1, 69117 Heidelberg, Germany
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