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Travnikova O, Kukk E, Hosseini F, Granroth S, Itälä E, Marchenko T, Guillemin R, Ismail I, Moussaoui R, Journel L, Bozek J, Püttner R, Krasnov P, Kimberg V, Gel'mukhanov F, Piancastelli MN, Simon M. Ultrafast dissociation of ammonia: Auger Doppler effect and redistribution of the internal energy. Phys Chem Chem Phys 2022; 24:5842-5854. [PMID: 35195639 DOI: 10.1039/d1cp05499f] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We study vibrationally-resolved resonant Auger (RAS) spectra of ammonia recorded in coincidence with the NH2+ fragment, which is produced in the course of dissociation either in the core-excited 1s-14a11 intermediate state or the first spectator 3a-24a11 final state. Correlation of the NH2+ ion flight times with electron kinetic energies allows directly observing the Auger-Doppler dispersion for each vibrational state of the fragment. The median distribution of the kinetic energy release EKER, derived from the coincidence data, shows three distinct branches as a function of Auger electron kinetic energy Ee: Ee + 1.75EKER = const for the molecular band; EKER = const for the fragment band; and Ee + EKER = const for the region preceding the fragment band. The deviation of the molecular band dispersion from Ee + EKER = const is attributed to the redistribution of the available energy to the dissociation energy and excitation of the internal degrees of freedom in the molecular fragment. We found that for each vibrational line the dispersive behavior of EKERvs. Ee is very sensitive to the instrumental uncertainty in the determination of EKER causing the competition between the Raman (EKER + Ee = const) and Auger (Ee = const) dispersions: increase in the broadening of the finite kinetic energy release resolution leads to a change of the dispersion from the Raman to the Auger one.
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Affiliation(s)
- Oksana Travnikova
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France.
| | - Edwin Kukk
- Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland
| | - Farzad Hosseini
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France. .,Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, F-91192 Gif-sur-Yvette Cedex, France
| | - Sari Granroth
- Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland
| | - Eero Itälä
- Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland
| | - Tatiana Marchenko
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France.
| | - Renaud Guillemin
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France.
| | - Iyas Ismail
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France.
| | - Roba Moussaoui
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France.
| | - Loïc Journel
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France.
| | - John Bozek
- Department of Physics and Astronomy, University of Turku, FI-20014 Turku, Finland
| | - Ralph Püttner
- Fachbereich Physik, Freie Universität Berlin, D-14195 Berlin, Germany
| | - Pavel Krasnov
- Department of Theoretical Chemistry and Biology, KTH Royal Institute of Technology, 10691 Stockholm, Sweden.,International Research Center of Spectroscopy and Quantum Chemistry - IRC SQC, Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Victor Kimberg
- Department of Theoretical Chemistry and Biology, KTH Royal Institute of Technology, 10691 Stockholm, Sweden.,International Research Center of Spectroscopy and Quantum Chemistry - IRC SQC, Siberian Federal University, 660041 Krasnoyarsk, Russia
| | - Faris Gel'mukhanov
- Department of Theoretical Chemistry and Biology, KTH Royal Institute of Technology, 10691 Stockholm, Sweden.,International Research Center of Spectroscopy and Quantum Chemistry - IRC SQC, Siberian Federal University, 660041 Krasnoyarsk, Russia.,Institute for Methods and Instrumentation in Synchrotron Radiation Research FG-ISRR, Helmholtz-Zentrum Berlin für Materialien und Energie, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
| | - Maria Novella Piancastelli
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France. .,Department of Physics and Astronomy, Uppsala University, SE-751 20 Uppsala, Sweden
| | - Marc Simon
- Sorbonne Université, CNRS, UMR 7614, Laboratoire de Chimie Physique-Matière et Rayonnement, F-75005 Paris, France.
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2
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Miao Q, Travnikova O, Gel'mukhanov F, Kimberg V, Sun YP, Thomas TD, Nicolas C, Patanen M, Miron C. Rotational Doppler Effect: A Probe for Molecular Orbitals Anisotropy. J Phys Chem Lett 2015; 6:1568-1572. [PMID: 26263315 DOI: 10.1021/acs.jpclett.5b00325] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The vibrationally resolved X-ray photoelectron spectra of X2Σg+(3σg−1) and B2Σu+(2σu−1) states of N2+ were recorded for different photon energies and orientations of the polarization vector. Clear dependencies of the spectral line widths on the X-ray polarization as well as on the symmetry of the final electronic states are observed. Contrary to the translational Doppler, the rotational Doppler broadening is sensitive to the photoelectron emission anisotropy. On the basis of theoretical modeling, we suggest that the different rotational Doppler broadenings observed for gerade and ungerade final states result from a Young's double-slit interference phenomenon.
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Affiliation(s)
- Quan Miao
- †Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, Roslagstullsbacken 15, S-10691 Stockholm, Sweden
- ‡Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
- §College of Electronics, Communication and Physics, Shandong University of Science and Technology, Qianwangang Road 579, Qingdao 266590 Shandong, People's Republic of China
| | - Oksana Travnikova
- ‡Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
| | - Faris Gel'mukhanov
- †Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, Roslagstullsbacken 15, S-10691 Stockholm, Sweden
- ‡Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
| | - Victor Kimberg
- †Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, Roslagstullsbacken 15, S-10691 Stockholm, Sweden
- ‡Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
| | - Yu-Ping Sun
- †Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, Roslagstullsbacken 15, S-10691 Stockholm, Sweden
- ∥School of Science, Shandong University of Technology, Xincunxi Road 266, ZiBo, 255049 Shandong, China
| | - T Darrah Thomas
- ⊥Department of Chemistry, Oregon State University, 153A Gilbert Hall, 2100 SW Campus Way, Corvallis, Oregon 97331, United States
| | - Christophe Nicolas
- ‡Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
| | - Minna Patanen
- ‡Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
| | - Catalin Miron
- ‡Synchrotron SOLEIL, l'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
- #Extreme Light Infrastructure - Nuclear Physics (ELI-NP), "Horia Hulubei" National Institute for Physics and Nuclear Engineering, 30 Reactorului Street, RO-077125 Măgurele, Jud. Ilfov, Romania
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3
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Ayuso D, Kimura M, Kooser K, Patanen M, Plésiat E, Argenti L, Mondal S, Travnikova O, Sakai K, Palacios A, Kukk E, Decleva P, Ueda K, Martín F, Miron C. Vibrationally Resolved B 1s Photoionization Cross Section of BF3. J Phys Chem A 2015; 119:5971-8. [DOI: 10.1021/jp511416h] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- D. Ayuso
- Departamento de
Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - M. Kimura
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
| | - K. Kooser
- Department
of Physics and Astronomy, University of Turku, 20014 Turku, Finland
| | - M. Patanen
- Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin,
BP 48, 91192 Gif-sur-Yvette
Cedex, France
| | - E. Plésiat
- Departamento de
Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - L. Argenti
- Departamento de
Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - S. Mondal
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
| | - O. Travnikova
- Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin,
BP 48, 91192 Gif-sur-Yvette
Cedex, France
| | - K. Sakai
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
| | - A. Palacios
- Departamento de
Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - E. Kukk
- Department
of Physics and Astronomy, University of Turku, 20014 Turku, Finland
| | - P. Decleva
- Dipartimento di Scienze Chimiche e Farmaceutiche, Università di Trieste and CNR–Istituto Officina dei Materiali, 34127 Trieste, Italy
| | - K. Ueda
- Institute
of Multidisciplinary Research for Advanced Materials, Tohoku University, Sendai 980-8577, Japan
| | - F. Martín
- Departamento de
Química, Módulo 13, Universidad Autónoma de Madrid, 28049 Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanociencia), Cantoblanco, 28049 Madrid, Spain
- Condensed Matter Physics
Center (IFIMAC), Universidad Autónoma de Madrid, 28049 Madrid, Spain
| | - C. Miron
- Synchrotron SOLEIL, L’Orme des Merisiers, Saint-Aubin,
BP 48, 91192 Gif-sur-Yvette
Cedex, France
- Extreme Light Infrastructure
- Nuclear Physics (ELI-NP), “Horia Hulubei” National Institute for Physics and Nuclear Engineering, 30 Reactorului Street, RO-077125 Măgurele, Jud.
Ilfov, Romania
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4
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Piancastelli MN, Guillemin R, Simon M, Iwayama H, Shigemasa E. Ultrafast dynamics in C 1s core-excited CF4 revealed by two-dimensional resonant Auger spectroscopy. J Chem Phys 2013; 138:234305. [PMID: 23802958 DOI: 10.1063/1.4810871] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Following core excitation in an isolated molecule, ultrafast dissociation of one particular chemical bond can occur, where "ultrafast" is defined as taking place during the lifetime of the core hole, of the order of few femtoseconds. The signature of such phenomenon can be observed in resonant Auger spectra following core excitation. We present here an investigation of ultrafast dissociation following C 1s-to-σ* core excitation in CF4, with high-resolution resonant Auger spectroscopy. We are able to characterize final states of both the molecular ion and the CF3 (+) fragment. We use two-dimensional (2D) maps to record resonant Auger spectra across the resonance as a function of photon energy and to characterize ultrafast dynamics. This method provides immediate visual evidence of one of the important characteristics of the study of spectral features related to molecular versus fragment ionic final states, and namely their dispersion law. In the 2D maps we are also able to identify the dissociation limit for one of the molecular final states.
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Affiliation(s)
- M N Piancastelli
- Laboratoire de Chimie Physique-Matière et Rayonnement, UPMC, Université Paris 06, CNRS, UMR 7614, 11 rue Pierre et Marie Curie, 75231 Paris Cedex 05, France.
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5
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Miao Q, Liu JC, Ågren H, Rubensson JE, Gel'mukhanov F. Dissociative x-ray lasing. PHYSICAL REVIEW LETTERS 2012; 109:233905. [PMID: 23368206 DOI: 10.1103/physrevlett.109.233905] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Revised: 06/25/2012] [Indexed: 06/01/2023]
Abstract
X-ray lasing is predicted to ensue when molecules are pumped into dissociative core-excited states by a free-electron-laser pulse. The lasing is due to the population inversion created in the neutral dissociation product, and the process features self-trapping of the x-ray pulse at the gain ridge. Simulations performed for the HCl molecule pumped at the 2p(1/2)→6σ resonance demonstrate that the scheme can be used to create ultrashort coherent x-ray pulses.
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Affiliation(s)
- Q Miao
- Theoretical Chemistry and Biology, School of Biotechnology, Royal Institute of Technology, S-106 91 Stockholm, Sweden.
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6
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Suzuki IH, Kono Y, Ikeda A, Ouchi T, Ueda K, Takahashi O, Higuchi I, Tamenori Y, Nagaoka S. Projection of Si 1s photoexcited orbitals into resonant Auger electron spectra in KLL decays of Si(CH3)4 and SiF4. J Chem Phys 2011; 134:084312. [PMID: 21361544 DOI: 10.1063/1.3556942] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Spectator resonant KL(23)L(23) Auger electron spectra have been measured in the Si 1s photoexcitation region of Si(CH(3))(4) using monochromatized undulator radiation combined with a hemispherical electron spectrometer. The broad peak with high intensity in a total ion yield spectrum, coming mainly from excitation of a 1s electron into the 6t(2) vacant orbital, induces a spectator Auger decay in which the excited electron remains in its excited orbital. The component on the higher energy side of this peak through 1s excitation into a Rydberg orbital produces resonant Auger decays in which the excited Rydberg electron moves into a slightly higher Rydberg orbital, or is partly shaken up to a significantly higher Rydberg orbital. These findings of Si(CH(3))(4) indicate a clear contrast to those for SiF(4), in which the 1s excitation into a Rydberg orbital induces a shake-down phenomenon as well as a shake-up one. The results of these molecules exhibit a clear splitting effect among excited orbitals which are smeared out by overlapping due to lifetime widths and due to densely populated levels in the 1s electron excitation spectrum. This is consistent with the calculation on photoexcitation within the framework of density functional theory.
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Affiliation(s)
- I H Suzuki
- Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), Tsukuba, Japan.
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7
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Travnikova O, Liu JC, Lindblad A, Nicolas C, Söderström J, Kimberg V, Gel'mukhanov F, Miron C. Circularly polarized x rays: another probe of ultrafast molecular decay dynamics. PHYSICAL REVIEW LETTERS 2010; 105:233001. [PMID: 21231455 DOI: 10.1103/physrevlett.105.233001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2010] [Indexed: 05/30/2023]
Abstract
Dissociative nuclear motion in core-excited molecular states leads to a splitting of the fragment Auger lines: the Auger-Doppler effect. We present here for the first time experimental evidence for an Auger-Doppler effect following F1s → a(1g)* inner-shell excitation by circularly polarized x rays in SF(6). In spite of a uniform distribution of the dissociating S-F bonds near the polarization plane of the light, the intersection between the subpopulation of molecules selected by the core excitation with the cone of dissociation induces a strong anisotropy in the distribution of the S-F bonds that contributes to the scattering profile measured in the polarization plane.
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Affiliation(s)
- Oksana Travnikova
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, F-91192 Gif-sur-Yvette Cedex, France
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8
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Miron C, Kimberg V, Morin P, Nicolas C, Kosugi N, Gavrilyuk S, Gel'mukhanov F. Vibrational scattering anisotropy generated by multichannel quantum interference. PHYSICAL REVIEW LETTERS 2010; 105:093002. [PMID: 20868156 DOI: 10.1103/physrevlett.105.093002] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/29/2010] [Indexed: 05/29/2023]
Abstract
Based on angularly and vibrationally resolved electron spectroscopy measurements in acetylene, we report the first observation of anomalously strong vibrational anisotropy of resonant Auger scattering through the C 1s→π* excited state. We provide a theoretical model explaining the new phenomenon by three coexisting interference effects: (i) interference between resonant and direct photoionization channels, (ii) interference of the scattering channels through the core-excited bending states with orthogonal orientation of the molecular orbitals, (iii) scattering through two wells of the double-well bending mode potential. The interplay of nuclear and electronic motions offers in this case a new type of nuclear wave packet interferometry sensitive to the anisotropy of nuclear dynamics: whether which-path information is available or not depends on the final vibrational state serving for path selection.
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Affiliation(s)
- Catalin Miron
- Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP 48, 91192 Gif-sur-Yvette Cedex, France
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9
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Suzuki IH, Nitta A, Fukuzawa H, Ueda K, Takahashi O, Tamenori Y, Nagaoka S. Site-specific behavior in de-excitation spectra of F(3)SiCH(2)CH(2)Si(CH(3))(3) in the Si 1s excitation region. J Chem Phys 2009; 131:164309. [PMID: 19894949 DOI: 10.1063/1.3257639] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Excitation (total ion yield) and de-excitation (resonant photoemission) spectra have been measured in the Si 1s photoexcitation region of the F(3)SiCH(2)CH(2)Si(CH(3))(3) molecule using monochromatized undulator radiation. Theoretical calculations within the framework of density functional theory have reproduced the observed total ion yield spectrum very well. The first peak at the lowest photon energy, coming from Si 1s excitation at the trimethyl side into a vacant orbital, induces spectator Auger decays in which the excited electron remains in its valence orbital. The second peak produced through excitation of Si 1s electron at the trifluoride side generates resonant Auger decays in which the excited valence electron remains predominantly also in the valence orbital or is partly shaken up into higher Rydberg orbitals. The third peak generated through Si 1s excitation at the trifluoride side produces resonant Auger decays in which the excited Rydberg electron remains or is partly shaken down to a lower lying valence molecular orbital. These findings exhibit a clear distinction between resonant Auger decays following photoexcitation of Si 1s electrons under different chemical environments.
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Affiliation(s)
- I H Suzuki
- Institute of Materials Structure Science, High Energy Accelerator Research Organization (KEK), 1-1 Oho, Tsukuba 305-0801, Japan.
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10
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Miron C, Morin P, Céolin D, Journel L, Simon M. Multipathway dissociation dynamics of core-excited methyl chloride probed by high resolution electron spectroscopy and Auger-electron–ion coincidences. J Chem Phys 2008; 128:154314. [DOI: 10.1063/1.2900645] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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11
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Mondal S, Singh RK, Shanker R. Doppler effect in fluorine K-Auger line produced in electron-induced core ionization of SF6. J Chem Phys 2006; 124:034301. [PMID: 16438577 DOI: 10.1063/1.2158995] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
An experimental evidence is reported on the observation of the Doppler effect in fluorine K-Auger line emitted from a core-ionized SF6 molecule under an impact of 16 keV electrons. The emitting source of the Auger line is found to acquire a kinetic energy of 4.7+/-0.3 keV. We propose that such large energy is released from the Coulomb repulsion taking place between F+ and SF5+ fragment ions under influence of an intense focusing field of the incident electrons. In the presence of the Coulomb field of these ions, the Auger line obtains a polarization P = 76%+/-7%.
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Affiliation(s)
- S Mondal
- Atomic Physics Laboratory, Department of Physics, Banaras Hindu University, Varanasi 221 005, India
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12
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Hjelte I, Björneholm O, Carravetta V, Angeli C, Cimiraglia R, Wiesner K, Svensson S, Piancastelli MN. Constant-atomic-final-state filtering of dissociative states in the O1s→σ* core excitation in O2. J Chem Phys 2005; 123:64314. [PMID: 16122315 DOI: 10.1063/1.1995689] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The below-threshold region in core-excited O2 is very complex, consisting of a multitude of exchange-split states with mixed molecular orbital-Rydberg character. We have investigated the nature of these intermediate states by resonant Auger spectroscopy. In particular, we have obtained constant-atomic-final-state yield curves for several atomic peaks in the electron decay spectra which are stemming from ultrafast dissociation. The relative intensity of Auger decay leading to atomic final states is considered a signature of the relative weight of the sigma* character. This method allows one to "filter out" intermediate states with dissociative character. Extensive calculations have been performed by multi-reference configuration interaction at different interatomic distances in order to evaluate the potential curves of the core-excited states and propose a qualitative description of the dissociative molecular dynamics. The calculations show that the core-excited states have a relevant admixture of excitations to orbitals with Rydberg character and excitations to the sigma* orbital with different spin couplings. A diabatization of the adiabatic potential curves shows that the coupling between Rydberg and sigma* diabatic states is very different at the different crossing points and ultrafast dissociation occurs more easily on the lowest sigma* diabatic potential curve. As a consequence, the observation of atomic peaks only in the lower-energy region of the absorption curve is well justified.
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Affiliation(s)
- I Hjelte
- Physics Department, Uppsala University, Uppsala, Sweden
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Kugeler O, Prümper G, Hentges R, Viefhaus J, Rolles D, Becker U, Marburger S, Hergenhahn U. Intramolecular electron scattering and electron transfer following autoionization in dissociating molecules. PHYSICAL REVIEW LETTERS 2004; 93:033002. [PMID: 15323819 DOI: 10.1103/physrevlett.93.033002] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2004] [Indexed: 05/24/2023]
Abstract
Resonant Auger decay of core-excited molecules during ultrafast dissociation leads to a Doppler shift of the emitted electrons depending on the direction of the electron emission relative to the dissociation axis. We have investigated this process by angle-resolved electron-fragment ion coincidence spectroscopy. Electron energy spectra for selected emission angles for the electron relative to the molecular axis reveal the occurrence of intermolecular electron scattering and electron transfer following the primary emission. These processes amount to approximately 25% of the resonant atomic Auger intensity emitted in the studied transition.
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Affiliation(s)
- O Kugeler
- Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin, Germany
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