1
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Robinson MS, Küpper J. Unraveling the ultrafast dynamics of thermal-energy chemical reactions. Phys Chem Chem Phys 2024; 26:1587-1601. [PMID: 38131437 DOI: 10.1039/d3cp03954d] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2023]
Abstract
In this perspective, we discuss how one can initiate, image, and disentangle the ultrafast elementary steps of thermal-energy chemical dynamics, building upon advances in technology and scientific insight. We propose that combinations of ultrashort mid-infrared laser pulses, controlled molecular species in the gas phase, and forefront imaging techniques allow to unravel the elementary steps of general-chemistry reaction processes in real time. We detail, for prototypical first reaction systems, experimental methods enabling these investigations, how to sufficiently prepare and promote gas-phase samples to thermal-energy reactive states with contemporary ultrashort mid-infrared laser systems, and how to image the initiated ultrafast chemical dynamics. The results of such experiments will clearly further our understanding of general-chemistry reaction dynamics.
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Affiliation(s)
- Matthew S Robinson
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
- Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Jochen Küpper
- Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany.
- Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
- Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
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2
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Kaye J, Barnett A, Greengard L, De Giovannini U, Rubio A. Eliminating Artificial Boundary Conditions in Time-Dependent Density Functional Theory Using Fourier Contour Deformation. J Chem Theory Comput 2023; 19:1409-1420. [PMID: 36786824 DOI: 10.1021/acs.jctc.2c01013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/15/2023]
Abstract
We present an efficient method for propagating the time-dependent Kohn-Sham equations in free space, based on the recently introduced Fourier contour deformation (FCD) approach. For potentials which are constant outside a bounded domain, FCD yields a high-order accurate numerical solution of the time-dependent Schrödinger equation directly in free space, without the need for artificial boundary conditions. Of the many existing artificial boundary condition schemes, FCD is most similar to an exact nonlocal transparent boundary condition, but it works directly on Cartesian grids in any dimension, and runs on top of the fast Fourier transform rather than fast algorithms for the application of nonlocal history integral operators. We adapt FCD to time-dependent density functional theory (TDDFT), and describe a simple algorithm to smoothly and automatically truncate long-range Coulomb-like potentials to a time-dependent constant outside of a bounded domain of interest, so that FCD can be used. This approach eliminates errors originating from the use of artificial boundary conditions, leaving only the error of the potential truncation, which is controlled and can be systematically reduced. The method enables accurate simulations of ultrastrong nonlinear electronic processes in molecular complexes in which the interference between bound and continuum states is of paramount importance. We demonstrate results for many-electron TDDFT calculations of absorption and strong field photoelectron spectra for one and two-dimensional models, and observe a significant reduction in the size of the computational domain required to achieve high quality results, as compared with the popular method of complex absorbing potentials.
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Affiliation(s)
- Jason Kaye
- Center for Computational Mathematics, Flatiron Institute, 162 5th Avenue, New York, New York 10010, United States.,Center for Computational Quantum Physics, Flatiron Institute, 162 5th Avenue, New York, New York 10010, United States
| | - Alex Barnett
- Center for Computational Mathematics, Flatiron Institute, 162 5th Avenue, New York, New York 10010, United States
| | - Leslie Greengard
- Center for Computational Mathematics, Flatiron Institute, 162 5th Avenue, New York, New York 10010, United States.,Courant Institute of Mathematical Sciences, New York University, 251 Mercer Street, New York, New York 10012, United States
| | - Umberto De Giovannini
- Dipartimento di Fisica e Chimica - Emilio Segrè, Università degli Studi di Palermo, Via Archirafi 36, I-90123, Palermo, Italy.,Max Planck Institute for the Structure and Dynamics of Matter and Center for Free Electron Laser Science, 22761, Hamburg, Germany
| | - Angel Rubio
- Center for Computational Quantum Physics, Flatiron Institute, 162 5th Avenue, New York, New York 10010, United States.,Max Planck Institute for the Structure and Dynamics of Matter and Center for Free Electron Laser Science, 22761, Hamburg, Germany
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3
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Chordiya K, Despré V, Nagyillés B, Zeller F, Diveki Z, Kuleff AI, Kahaly MU. Photo-ionization initiated differential ultrafast charge migration: impacts of molecular symmetries and tautomeric forms. Phys Chem Chem Phys 2023; 25:4472-4480. [PMID: 36317562 DOI: 10.1039/d2cp02681c] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Photo-ionization induced ultrafast electron dynamics is considered as a precursor for the slower nuclear dynamics associated with molecular dissociation. Here, using the ab initio multielectron wave-packet propagation method, we study the overall many-electron dynamics, triggered by ionizing the outer-valence orbitals of different tautomers for a prototype molecule with more than one symmetry element. From the time evolution of the initially created averaged hole density of each system, we identify distinctly different charge dynamics responses in the tautomers. We observe that the keto form shows a charge migration direction away from the nitrogen bonded with hydrogen, while in enol-U - away from oxygen bonded to hydrogen. Additionally, the dynamics following the ionization of molecular orbitals with different symmetries reveals that a' orbitals show a fast and highly delocalized charge density in comparison to a'' symmetry. These observations indicate why different tautomers respond differently to an XUV ionization, and might explain the subsequent different fragmentation pathways. An experimental schematics allowing the detection and reconstruction of such charge dynamics is also proposed. Although the present study uses a simple, prototypical bio-relevant molecule, it reveals the explicit role of molecular symmetry and tautomerism in the ionization-triggered charge migration that controls many ultrafast physical, chemical, and biological processes, making tautomeric forms a promising tool of molecular design for desired charge migration.
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Affiliation(s)
- Kalyani Chordiya
- ELI-ALPS, ELI-HU Non-Profit Ltd., Wolfgang Sandner utca 3., Szeged, H-6728, Hungary. .,Institute of Physics, University of Szeged, Dóm tér 9, H-6720, Szeged, Hungary
| | - Victor Despré
- Theoretische Chemie, Universität Heidelberg, Im Neuenheimer Feld 229, D-69120, Heidelberg, Germany.
| | - Balázs Nagyillés
- ELI-ALPS, ELI-HU Non-Profit Ltd., Wolfgang Sandner utca 3., Szeged, H-6728, Hungary. .,Institute of Physics, University of Szeged, Dóm tér 9, H-6720, Szeged, Hungary
| | - Felix Zeller
- Theoretische Chemie, Universität Heidelberg, Im Neuenheimer Feld 229, D-69120, Heidelberg, Germany.
| | - Zsolt Diveki
- ELI-ALPS, ELI-HU Non-Profit Ltd., Wolfgang Sandner utca 3., Szeged, H-6728, Hungary.
| | - Alexander I Kuleff
- ELI-ALPS, ELI-HU Non-Profit Ltd., Wolfgang Sandner utca 3., Szeged, H-6728, Hungary. .,Theoretische Chemie, Universität Heidelberg, Im Neuenheimer Feld 229, D-69120, Heidelberg, Germany.
| | - Mousumi Upadhyay Kahaly
- ELI-ALPS, ELI-HU Non-Profit Ltd., Wolfgang Sandner utca 3., Szeged, H-6728, Hungary. .,Institute of Physics, University of Szeged, Dóm tér 9, H-6720, Szeged, Hungary
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4
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Onvlee J, Trippel S, Küpper J. Ultrafast light-induced dynamics in the microsolvated biomolecular indole chromophore with water. Nat Commun 2022; 13:7462. [PMID: 36460654 PMCID: PMC9718776 DOI: 10.1038/s41467-022-33901-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2021] [Accepted: 10/04/2022] [Indexed: 12/05/2022] Open
Abstract
Interactions between proteins and their solvent environment can be studied in a bottom-up approach using hydrogen-bonded chromophore-solvent clusters. The ultrafast dynamics following UV-light-induced electronic excitation of the chromophores, potential radiation damage, and their dependence on solvation are important open questions. The microsolvation effect is challenging to study due to the inherent mix of the produced gas-phase aggregates. We use the electrostatic deflector to spatially separate different molecular species in combination with pump-probe velocity-map-imaging experiments. We demonstrate that this powerful experimental approach reveals intimate details of the UV-induced dynamics in the near-UV-absorbing prototypical biomolecular indole-water system. We determine the time-dependent appearance of the different reaction products and disentangle the occurring ultrafast processes. This approach ensures that the reactants are well-known and that detailed characteristics of the specific reaction products are accessible - paving the way for the complete chemical-reactivity experiment.
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Affiliation(s)
- Jolijn Onvlee
- grid.7683.a0000 0004 0492 0453Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany ,grid.9026.d0000 0001 2287 2617Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany ,grid.5590.90000000122931605Institute for Molecules and Materials, Radboud University, Nijmegen, The Netherlands
| | - Sebastian Trippel
- grid.7683.a0000 0004 0492 0453Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany ,grid.9026.d0000 0001 2287 2617Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Jochen Küpper
- grid.7683.a0000 0004 0492 0453Center for Free-Electron Laser Science CFEL, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany ,grid.9026.d0000 0001 2287 2617Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany ,grid.9026.d0000 0001 2287 2617Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
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5
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Haags A, Yang X, Egger L, Brandstetter D, Kirschner H, Bocquet FC, Koller G, Gottwald A, Richter M, Gottfried JM, Ramsey MG, Puschnig P, Soubatch S, Tautz FS. Momentum space imaging of σ orbitals for chemical analysis. SCIENCE ADVANCES 2022; 8:eabn0819. [PMID: 35867796 PMCID: PMC9307240 DOI: 10.1126/sciadv.abn0819] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Accepted: 06/09/2022] [Indexed: 06/15/2023]
Abstract
Tracing the modifications of molecules in surface chemical reactions benefits from the possibility to image their orbitals. While delocalized frontier orbitals with π character are imaged routinely with photoemission orbital tomography, they are not always sensitive to local chemical modifications, particularly the making and breaking of bonds at the molecular periphery. For such bonds, σ orbitals would be far more revealing. Here, we show that these orbitals can indeed be imaged in a remarkably broad energy range and that the plane wave approximation, an important ingredient of photoemission orbital tomography, is also well fulfilled for these orbitals. This makes photoemission orbital tomography a unique tool for the detailed analysis of surface chemical reactions. We demonstrate this by identifying the reaction product of a dehalogenation and cyclodehydrogenation reaction.
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Affiliation(s)
- Anja Haags
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, Jülich, Germany
- Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, Germany
- Experimentalphysik IV A, RWTH Aachen University, Aachen, Germany
| | - Xiaosheng Yang
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, Jülich, Germany
- Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, Germany
- Experimentalphysik IV A, RWTH Aachen University, Aachen, Germany
| | - Larissa Egger
- Institut für Physik, Karl-Franzens-Universität Graz, NAWI Graz, Graz, Austria
| | | | - Hans Kirschner
- Physikalisch-Technische Bundesanstalt (PTB), Berlin, Germany
| | - François C. Bocquet
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, Jülich, Germany
- Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, Germany
| | - Georg Koller
- Institut für Physik, Karl-Franzens-Universität Graz, NAWI Graz, Graz, Austria
| | | | - Mathias Richter
- Physikalisch-Technische Bundesanstalt (PTB), Berlin, Germany
| | | | - Michael G. Ramsey
- Institut für Physik, Karl-Franzens-Universität Graz, NAWI Graz, Graz, Austria
| | - Peter Puschnig
- Institut für Physik, Karl-Franzens-Universität Graz, NAWI Graz, Graz, Austria
| | - Serguei Soubatch
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, Jülich, Germany
- Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, Germany
| | - F. Stefan Tautz
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, Jülich, Germany
- Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, Jülich, Germany
- Experimentalphysik IV A, RWTH Aachen University, Aachen, Germany
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6
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Mullins T, Karamatskos ET, Wiese J, Onvlee J, Rouzée A, Yachmenev A, Trippel S, Küpper J. Picosecond pulse-shaping for strong three-dimensional field-free alignment of generic asymmetric-top molecules. Nat Commun 2022; 13:1431. [PMID: 35301292 PMCID: PMC8931173 DOI: 10.1038/s41467-022-28951-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2020] [Accepted: 02/15/2022] [Indexed: 11/09/2022] Open
Abstract
Fixing molecules in space is a crucial step for the imaging of molecular structure and dynamics. Here, we demonstrate three-dimensional (3D) field-free alignment of the prototypical asymmetric top molecule indole using elliptically polarized, shaped, off-resonant laser pulses. A truncated laser pulse is produced using a combination of extreme linear chirping and controlled phase and amplitude shaping using a spatial-light-modulator (SLM) based pulse shaper of a broadband laser pulse. The angular confinement is detected through velocity-map imaging of H+ and C2+ fragments resulting from strong-field ionization and Coulomb explosion of the aligned molecules by intense femtosecond laser pulses. The achieved three-dimensional alignment is characterized by comparing the result of ion-velocity-map measurements for different alignment directions and for different times during and after the alignment laser pulse to accurate computational results. The achieved strong three-dimensional field-free alignment of [Formula: see text] demonstrates the feasibility of both, strong three-dimensional alignment of generic complex molecules and its quantitative characterization.
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Affiliation(s)
- Terry Mullins
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany
| | - Evangelos T Karamatskos
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany.,Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Joss Wiese
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany.,Department of Chemistry, Universität Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany.,Center for Ultrafast Imaging, Universität of Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Jolijn Onvlee
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany.,Center for Ultrafast Imaging, Universität of Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany.,Institute for Molecules and Materials, Radboud University, Heijendaalseweg 135, 6525 AJ, Nijmegen, The Netherlands
| | - Arnaud Rouzée
- Max Born Institute, Max-Born-Straße 2a, 12489, Berlin, Germany
| | - Andrey Yachmenev
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany.,Center for Ultrafast Imaging, Universität of Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Sebastian Trippel
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany.,Center for Ultrafast Imaging, Universität of Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany
| | - Jochen Küpper
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607, Hamburg, Germany. .,Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany. .,Department of Chemistry, Universität Hamburg, Martin-Luther-King-Platz 6, 20146, Hamburg, Germany. .,Center for Ultrafast Imaging, Universität of Hamburg, Luruper Chaussee 149, 22761, Hamburg, Germany.
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7
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Dowek D, Decleva P. Trends in angle-resolved molecular photoelectron spectroscopy. Phys Chem Chem Phys 2022; 24:24614-24654. [DOI: 10.1039/d2cp02725a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023]
Abstract
In this perspective article, main trends of angle-resolved molecular photoelectron spectroscopy in the laboratory up to the molecular frame, in different regimes of light-matter interactions, are highlighted with emphasis on foundations and most recent applications.
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Affiliation(s)
- Danielle Dowek
- Université Paris-Saclay, CNRS, Institut des Sciences Moléculaires d’Orsay, 91405 Orsay, France
| | - Piero Decleva
- CNR IOM and Dipartimento DSCF, Università di Trieste, Trieste, Italy
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8
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Ortmann L, AlShafey A, Staudte A, Landsman AS. Tracking the Ionization Site in Neutral Molecules. PHYSICAL REVIEW LETTERS 2021; 127:213201. [PMID: 34860111 DOI: 10.1103/physrevlett.127.213201] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Revised: 09/19/2021] [Accepted: 10/15/2021] [Indexed: 06/13/2023]
Abstract
When a diatomic molecule is exposed to intense light, the valence electron may tunnel from a higher potential (corresponding to an upfield atom) due to the suppressed internuclear barrier. This process is known as ionization enhancement and is a key mechanism in strong field ionization of molecules. Alternatively, the bound electron wave function can evolve adiabatically in the laser field, resulting in ionization from the downfield atom. Here, we introduce a method to quantify the relative contribution of these two processes. Applying this method to experimentally measured electron momenta distributions following strong field ionization of N_{2} with infrared laser light, we find approximately a 2∶1 ratio of electrons ionized from a downfield atom, relative to upfield. This suggests that the bound state wave function largely adapts adiabatically to the changing laser field, although the nonadiabatic process of ionization enhancement still contributes even in neutral molecules. Our method can be applied to any diatomic neutral molecule to better understand the evolution of the initially bound electron wave packet and hence the nature of the molecular ionization process.
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Affiliation(s)
- L Ortmann
- Max Planck Institute for the Physics of Complex Systems, Nöthnitzer Straße 38, D-01187 Dresden, Germany
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - A AlShafey
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
| | - A Staudte
- Joint Attosecond Science Lab of the National Research Council and the University of Ottawa, Ottawa, Ontario K1A 0R6, Canada
| | - A S Landsman
- Department of Physics, The Ohio State University, Columbus, Ohio 43210, USA
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9
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Sun F, Lu C, Ma Y, Pan S, Wang J, Zhang W, Qiang J, Chen F, Ni H, Li H, Wu J. Orbital effects in strong-field Rydberg state excitation of N 2, Ar, O 2 and Xe. OPTICS EXPRESS 2021; 29:31240-31248. [PMID: 34615224 DOI: 10.1364/oe.437437] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2021] [Accepted: 09/02/2021] [Indexed: 06/13/2023]
Abstract
Rather than being freed to the continuum, the strong-field tunneled electrons can make a trajectory driven by the remaining laser fields and have certain probability to be captured by the high lying Rydberg states of the parent atoms or molecules. To explore the effect of molecular orbital on Rydberg state excitation, the ellipticity dependence of Rydberg state yields of N2 and O2 molecules are experimentally investigated using cold target recoil ion momentum spectroscopy and are compared with their counterpart atoms Ar and Xe with comparable ionization potentials. We found the generation probability of the neutral Rydberg fragment O2* was orders of magnitude higher than that of Xe* due to the butterfly-shaped highest occupied molecular orbital of O2. Meanwhile, our experimental and simulation results reveal that it is the initial momentum distribution (determined by the detailed characteristics of orbitals) that finally leads to the tendency that the Rydberg state yield of O2 (Ar) decreased slower than that obtained for Xe (N2) when the ellipticity of the excitation laser field is increased.
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10
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Karamatskos ET, Yarlagadda S, Patchkovskii S, Vrakking MJJ, Welsch R, Küpper J, Rouzée A. Time-resolving the UV-initiated photodissociation dynamics of OCS. Faraday Discuss 2021; 228:413-431. [PMID: 33570531 DOI: 10.1039/d0fd00119h] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
We present a time-resolved study of the photodissociation dynamics of OCS after UV-photoexcitation at λ = 237 nm. OCS molecules (X1Σ+) were primarily excited to the 11A'' and the 21A' Renner-Teller components of the 1Σ- and 1Δ states. Dissociation into CO and S fragments was observed through time-delayed strong-field ionisation and imaging of the kinetic energy of the resulting CO+ and S+ fragments by intense 790 nm laser pulses. Surprisingly, fast oscillations with a period of ∼100 fs were observed in the S+ channel of the UV dissociation. Based on wavepacket-dynamics simulations coupled with a simple electrostatic-interaction model, these oscillations do not correspond to the known highly-excited rotational motion of the leaving CO(X1Σ+, J ≫ 0) fragments, which has a timescale of ∼140 fs. Instead, we suggest to assign the observed oscillations to the excitation of vibrational wavepackets in the 23A'' or 21A'' states of the molecule that predissociate to form S(3PJ) photoproducts.
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Affiliation(s)
- Evangelos T Karamatskos
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany. and Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | | | | | | | - Ralph Welsch
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany. and Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Jochen Küpper
- Center for Free-Electron Laser Science, Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, 22607 Hamburg, Germany. and Department of Physics, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany and Center for Ultrafast Imaging, Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Arnaud Rouzée
- Max Born Institute, Max-Born-Straße 2a, 12489 Berlin, Germany.
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11
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Bhan L, Covington C, Rivas J, Varga K. Simulation of photo-electron spectrum and electron scattering by dual time propagation. J Chem Phys 2021; 154:114110. [PMID: 33752384 DOI: 10.1063/5.0045591] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
A dual time propagation approach is introduced to describe electron scattering and ionization. The space is divided into two regions, a central region with a full time-dependent Hamiltonian and an outer region where the kinetic operator and the laser field dominate. The two regions are connected by a source term. Time-dependent density functional theory calculations of wave packet scattering on molecules and photoelectron spectrum due to circularly polarized laser are presented to illustrate the efficiency and applicability of the approach.
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Affiliation(s)
- Luke Bhan
- Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235, USA
| | - Cody Covington
- Department of Chemistry, Austin Peay State University, Clarksville, Tennessee 37044, USA
| | - Jason Rivas
- Department of Chemistry, Austin Peay State University, Clarksville, Tennessee 37044, USA
| | - Kálmán Varga
- Department of Physics and Astronomy, Vanderbilt University, Nashville, Tennessee 37235, USA
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12
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Wallauer R, Raths M, Stallberg K, Münster L, Brandstetter D, Yang X, Güdde J, Puschnig P, Soubatch S, Kumpf C, Bocquet FC, Tautz FS, Höfer U. Tracing orbital images on ultrafast time scales. Science 2021; 371:1056-1059. [PMID: 33602865 DOI: 10.1126/science.abf3286] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Accepted: 02/01/2021] [Indexed: 11/02/2022]
Abstract
Frontier orbitals determine fundamental molecular properties such as chemical reactivities. Although electron distributions of occupied orbitals can be imaged in momentum space by photoemission tomography, it has so far been impossible to follow the momentum-space dynamics of a molecular orbital in time, for example, through an excitation or a chemical reaction. Here, we combined time-resolved photoemission using high laser harmonics and a momentum microscope to establish a tomographic, femtosecond pump-probe experiment of unoccupied molecular orbitals. We measured the full momentum-space distribution of transiently excited electrons, connecting their excited-state dynamics to real-space excitation pathways. Because in molecules this distribution is closely linked to orbital shapes, our experiment may, in the future, offer the possibility of observing ultrafast electron motion in time and space.
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Affiliation(s)
- R Wallauer
- Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany
| | - M Raths
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany.,Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, 52425 Jülich, Germany.,Experimentalphysik IV A, RWTH Aachen University, Otto-Blumenthal-Straße, 52074 Aachen, Germany
| | - K Stallberg
- Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany
| | - L Münster
- Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany
| | - D Brandstetter
- Institute of Physics, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - X Yang
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany.,Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, 52425 Jülich, Germany.,Experimentalphysik IV A, RWTH Aachen University, Otto-Blumenthal-Straße, 52074 Aachen, Germany
| | - J Güdde
- Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany
| | - P Puschnig
- Institute of Physics, University of Graz, NAWI Graz, 8010 Graz, Austria
| | - S Soubatch
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany.,Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - C Kumpf
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany.,Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, 52425 Jülich, Germany.,Experimentalphysik IV A, RWTH Aachen University, Otto-Blumenthal-Straße, 52074 Aachen, Germany
| | - F C Bocquet
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany.,Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, 52425 Jülich, Germany
| | - F S Tautz
- Peter Grünberg Institut (PGI-3), Forschungszentrum Jülich, 52425 Jülich, Germany. .,Jülich Aachen Research Alliance (JARA), Fundamentals of Future Information Technology, 52425 Jülich, Germany.,Experimentalphysik IV A, RWTH Aachen University, Otto-Blumenthal-Straße, 52074 Aachen, Germany
| | - U Höfer
- Fachbereich Physik und Zentrum für Materialwissenschaften, Philipps-Universität Marburg, Renthof 5, 35032 Marburg, Germany.
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