1
|
Ash R, Abhari Z, Candela R, Welke N, Murawski J, Gardezi SM, Venkatasubramanian N, Munawar M, Siewert F, Sokolov A, LaDuca Z, Kawasaki J, Bergmann U. X-FAST: A versatile, high-throughput, and user-friendly XUV femtosecond absorption spectroscopy tabletop instrument. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2023; 94:073004. [PMID: 37462459 DOI: 10.1063/5.0146137] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 06/25/2023] [Indexed: 07/21/2023]
Abstract
We present the X-FAST (XUV Femtosecond Absorption Spectroscopy Tabletop) instrument at the University of Wisconsin-Madison. The instrument produces femtosecond extreme ultraviolet photon pulses via high-harmonic generation in the range of 40-72 eV, as well as optical pump pulses for transient-absorption experiments. The system implements a gas-cooled sample cell that enables studying the dynamics of thermally sensitive thin-film samples. This paper provides potential users with specifications of the optical, vacuum, data acquisition, and sample cooling systems of the X-FAST instrument, along with performance metrics and data of an ultrafast laser-induced phase transition in a Ni2MnGa Heusler thin film.
Collapse
Affiliation(s)
- Ryan Ash
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| | - Zain Abhari
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| | - Roberta Candela
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| | - Noah Welke
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| | - Jake Murawski
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| | - S Minhal Gardezi
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| | | | - Muneeza Munawar
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| | - Frank Siewert
- Helmholtz Zentrum Berlin für Materialien und Energie, Department of Optics and Beamlines, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - Andrey Sokolov
- Helmholtz Zentrum Berlin für Materialien und Energie, Department of Optics and Beamlines, Albert-Einstein-Str. 15, 12489 Berlin, Germany
| | - Zachary LaDuca
- Department of Materials Science and Engineering, University of Wisconsin Madison, 1509 University Ave., Madison, Wisconsin 53706, USA
| | - Jason Kawasaki
- Department of Materials Science and Engineering, University of Wisconsin Madison, 1509 University Ave., Madison, Wisconsin 53706, USA
| | - Uwe Bergmann
- Department of Physics, University of Wisconsin Madison, 1150 University Ave., Madison, Wisconsin 53706, USA
| |
Collapse
|
2
|
Loh ZH. Studies of Ultrafast Molecular Dynamics by Femtosecond Extreme Ultraviolet Absorption Spectroscopy. CHEM LETT 2021. [DOI: 10.1246/cl.200940] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Zhi-Heng Loh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| |
Collapse
|
3
|
Rott F, Reduzzi M, Schnappinger T, Kobayashi Y, Chang KF, Timmers H, Neumark DM, de Vivie-Riedle R, Leone SR. Ultrafast strong-field dissociation of vinyl bromide: An attosecond transient absorption spectroscopy and non-adiabatic molecular dynamics study. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2021; 8:034104. [PMID: 34169117 PMCID: PMC8208825 DOI: 10.1063/4.0000102] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Accepted: 05/24/2021] [Indexed: 06/13/2023]
Abstract
Attosecond extreme ultraviolet (XUV) and soft x-ray sources provide powerful new tools for studying ultrafast molecular dynamics with atomic, state, and charge specificity. In this report, we employ attosecond transient absorption spectroscopy (ATAS) to follow strong-field-initiated dynamics in vinyl bromide. Probing the Br M edge allows one to assess the competing processes in neutral and ionized molecular species. Using ab initio non-adiabatic molecular dynamics, we simulate the neutral and cationic dynamics resulting from the interaction of the molecule with the strong field. Based on the dynamics results, the corresponding time-dependent XUV transient absorption spectra are calculated by applying high-level multi-reference methods. The state-resolved analysis obtained through the simulated dynamics and related spectral contributions enables a detailed and quantitative comparison with the experimental data. The main outcome of the interaction with the strong field is unambiguously the population of the first three cationic states, D 1, D 2, and D 3. The first two show exclusively vibrational dynamics while the D 3 state is characterized by an ultrafast dissociation of the molecule via C-Br bond rupture within 100 fs in 50% of the analyzed trajectories. The combination of the three simulated ionic transient absorption spectra is in excellent agreement with the experimental results. This work establishes ATAS in combination with high-level multi-reference simulations as a spectroscopic technique capable of resolving coupled non-adiabatic electronic-nuclear dynamics in photoexcited molecules with sub-femtosecond resolution.
Collapse
Affiliation(s)
- Florian Rott
- Department of Chemistry, LMU Munich, 81377 Munich, Germany
| | - Maurizio Reduzzi
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | | | - Yuki Kobayashi
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Kristina F. Chang
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Henry Timmers
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | | | | | | |
Collapse
|
4
|
Zhou L, Liu Y, Sun T, Yin H, Zhao Y, Lv H, Xu H. Strong Field Ionization-Photofragmentation on Ultrafast Evolution of Electronic States of Toluene Cations. J Phys Chem A 2021; 125:2095-2100. [PMID: 33662205 DOI: 10.1021/acs.jpca.0c11547] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ultrafast time-resolved strong field ionization-photofragmentation (SFI-PF) has emerged as a useful method for investigation of dynamics of molecular cations. Here we perform a SFI-PF study on the electronic states of toluene cations. By measuring the ion yields as a function of delay time, we obtain the transients of both parent and daughter ions, which show ultrafast decays and out-of-phase oscillations. The results provide the first experimental evidence of D1-D0 ultrafast relaxation of toluene cations occurring in about 530 fs and indicate coincident resonance between the vibrational states in D1 and D0 leading to oscillations with a period of about 2.05 ps. Our study should shed some light on the ultrafast photochemistry involving complex molecular cations.
Collapse
Affiliation(s)
- Longxing Zhou
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Yang Liu
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Tian Sun
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Hang Yin
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Yiwen Zhao
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Hang Lv
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| | - Haifeng Xu
- Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China
| |
Collapse
|
5
|
Wei Z, Li J, Zhang H, Lu Y, Yang M, Loh ZH. Ultrafast dissociative ionization and large-amplitude vibrational wave packet dynamics of strong-field-ionized di-iodomethane. J Chem Phys 2019; 151:214308. [PMID: 31822095 DOI: 10.1063/1.5132967] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We employ few-cycle pulses to strong-field-ionize di-iodomethane (CH2I2) and femtosecond extreme ultraviolet (XUV) transient absorption spectroscopy to investigate the subsequent ultrafast dissociative ionization and vibrational wave packet dynamics. Probing in the spectral region of the I 4d core-level transitions, the time-resolved XUV differential absorption spectra reveal the population of several electronic states of CH2I2 + by strong-field ionization. Global analysis reveals three distinct time scales for the observed dynamics: 20 ± 2 fs, 49 ± 6 fs, and 157 ± 9 fs, ascribed to relaxation of the CH2I2 + parent ion from the Franck-Condon region, dissociation of high-lying excited states of CH2I2 + to I+ (3P2), CH2I, and I2 + (2Π3/2,g), and dissociation of CH2I2 + to I (2P3/2) and CH2I+, respectively. Oscillatory features in the time-resolved XUV differential absorption spectra point to the generation of vibrational wave packets in both the residual CH2I2 and the CH2I2 + parent ion. Analysis of the oscillation frequencies and phases reveals, in the case of neutral CH2I2, C-I symmetric stretching induced by bond softening and I-C-I bending driven by a combination of bond softening and R-selective depletion. In the case of CH2I2 +, both the fundamental and first overtone frequencies of the I-C-I bending mode are observed, indicating large-amplitude I-C-I bending motion, in good agreement with results obtained from ab initio simulations of the XUV transition energy along the I-C-I bend coordinate. These results show that femtosecond XUV absorption spectroscopy is well-suited for studying ultrafast photodissociation and vibrational wave packet dynamics.
Collapse
Affiliation(s)
- Zhengrong Wei
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Jialin Li
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Huimin Zhang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Yunpeng Lu
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Minghui Yang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Zhi-Heng Loh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| |
Collapse
|
6
|
Lackner F, Chatterley AS, Toulson BW, Neumark DM, Leone SR, Gessner O. Photo-induced dynamics in bromoform molecules studied by femtosecond XUV transient absorption spectroscopy. EPJ WEB OF CONFERENCES 2019. [DOI: 10.1051/epjconf/201920506003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Ultrafast dissociation dynamics in bromoform molecules initiated by UV (263 nm) excitation and by strong-field ionization are explored using femtosecond XUV transient absorption spectroscopy.
Collapse
|
7
|
Kobayashi Y, Zeng T, Neumark DM, Leone SR. Ab initio investigation of Br-3 d core-excited states in HBr and HBr + toward XUV probing of photochemical dynamics. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2019; 6:014101. [PMID: 30868084 PMCID: PMC6404917 DOI: 10.1063/1.5085011] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2018] [Accepted: 01/09/2019] [Indexed: 05/11/2023]
Abstract
Ultrafast X-ray/XUV transient absorption spectroscopy is a powerful tool for real-time probing of chemical dynamics. Interpretation of the transient absorption spectra requires knowledge of core-excited potentials, which necessitates assistance from high-level electronic-structure computations. In this study, we investigate Br-3d core-excited electronic structures of hydrogen bromide (HBr) using spin-orbit general multiconfigurational quasidegenerate perturbation theory (SO-GMC-QDPT). Potential energy curves and transition dipole moments are calculated from the Franck-Condon region to the asymptotic limit and used to construct core-to-valence absorption strengths for five electronic states of HBr (Σ 1 0 + , 3 Π 1 , 1 Π 1 , 3 Π 0 + , 3 Σ 1 ) and two electronic states of HBr+ (2Π3∕2, 2Σ1∕2). The results illustrate the capabilities of Br-3d edge probing to capture transitions of the electronic-state symmetry as well as nonadiabatic dissociation processes that evolve across avoided crossings. Furthermore, core-to-valence absorption spectra are simulated from the neutralΣ 1 0 + state and the ionicΠ 2 1 / 2 , 3 / 2 states by numerically solving the time-dependent Schrödinger equation and exhibit excellent agreement with the experimental spectrum. The comprehensive and quantitative picture of the core-excited states obtained in this work allows for transparent analysis of the core-to-valence absorption signals, filling gaps in the theoretical understanding of the Br-3d transient absorption spectra.
Collapse
Affiliation(s)
- Yuki Kobayashi
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Tao Zeng
- Department of Chemistry, Carleton University, Ottawa, Ontario K1S5B6, Canada
| | | | | |
Collapse
|
8
|
Wei Z, Tian L, Li J, Lu Y, Yang M, Loh ZH. Tracking Ultrafast Bond Dissociation Dynamics at 0.1 Å Resolution by Femtosecond Extreme Ultraviolet Absorption Spectroscopy. J Phys Chem Lett 2018; 9:5742-5747. [PMID: 30212632 DOI: 10.1021/acs.jpclett.8b02547] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Visualizing the real-time dissociation of chemical bonds represents a challenge in the study of ultrafast molecular dynamics due to the simultaneous need for sub-angstrom spatial and femtosecond temporal resolution. Here, we follow the C-I dissociation dynamics of strong-field-ionized 2-iodopropane (2-C3H7I) with femtosecond extreme ultraviolet (XUV) absorption spectroscopy. By probing the iodine 4 d core-level absorption, we resolve a continuous XUV spectral shift on the sub-100 fs time scale that accompanies the dissociation of the 2-C3H7I+ spin-orbit-excited 2 E1/2 state to yield atomic I in the 2 P3/2 state. In combination with ab initio calculations of the C-I distance-dependent XUV transition energy, we reconstruct the temporal evolution of the C-I distance from the Franck-Condon region to the asymptotic region with 10 fs and 0.1 Å resolution. The C-I bond elongation appears to couple to coherent vibrational motion along the HC(CH3)2 umbrella mode of the 2-C3H7+ fragment, whose effect on the I 4 d XUV transition even at C-I distances of 3.5 Å points to the long-range nature of XUV absorption probing. Our results suggest that femtosecond XUV absorption spectroscopy, in combination with ab initio simulations of XUV transition energies, can be used to resolve the ultrafast structural dynamics of large polyatomic molecules.
Collapse
Affiliation(s)
- Zhengrong Wei
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371
| | - Li Tian
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics , Chinese Academy of Sciences , Wuhan 430071 , China
| | - Jialin Li
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371
| | - Yunpeng Lu
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371
| | - Minghui Yang
- Key Laboratory of Magnetic Resonance in Biological Systems, State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, National Center for Magnetic Resonance in Wuhan, Wuhan Institute of Physics and Mathematics , Chinese Academy of Sciences , Wuhan 430071 , China
| | - Zhi-Heng Loh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371
- Division of Physics and Applied Physics, School of Physical and Mathematical Sciences , Nanyang Technological University , Singapore 637371
- Centre for Optical Fibre Technology, The Photonics Institute , Nanyang Technological University , Singapore 639798
| |
Collapse
|
9
|
Wei Z, Li J, See ST, Loh ZH. Spin-Orbit State-Selective C-I Dissociation Dynamics of the CH 3I + X̃ Electronic State Induced by Intense Few-Cycle Laser Fields. J Phys Chem Lett 2017; 8:6067-6072. [PMID: 29190098 DOI: 10.1021/acs.jpclett.7b03022] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Studies of ultrafast molecular dynamics induced by intense laser fields can reveal new approaches to manipulating chemical reactions in the strong-field regime. Here, we show that intense few-cycle laser pulses can induce the spin-orbit state-selective C-I dissociation of the iodomethane cation (CH3I+) in the X̃ electronic state. Irradiation of CH3I by 6 fs laser pulses with peak intensities of 1.9 × 1014 W/cm2 followed by femtosecond extreme ultraviolet probing of the iodine 4d core-level transitions reveals dissociation of the CH3I+ X̃ 2E1/2 state with a time constant of 0.76 ± 0.16 ps. By contrast, the X̃ 2E3/2 spin-orbit ground state does not exhibit any appreciable dissociation on the picosecond time scale. The observed spin-orbit state-selective dissociation of the X̃ state is rationalized in terms of the laser-induced coupling to the à state. Our results suggest that the intense-laser control of photodissociation channels can be potentially extended to spin-orbit split states.
Collapse
Affiliation(s)
- Zhengrong Wei
- Division of Chemistry and Biological Chemistry and Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore
| | - Jialin Li
- Division of Chemistry and Biological Chemistry and Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore
| | - Soo Teck See
- Division of Chemistry and Biological Chemistry and Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore
| | - Zhi-Heng Loh
- Division of Chemistry and Biological Chemistry and Division of Physics and Applied Physics, School of Physical and Mathematical Sciences, Nanyang Technological University , Singapore 637371, Singapore
- Centre for Optical Fibre Technology, The Photonics Institute, Nanyang Technological University , Singapore 639798, Singapore
| |
Collapse
|
10
|
Luo S, Hu W, Yu J, Li X, He L, Wang C, Liu F, Ding D. Multielectron Effects in the Strong Field Sequential Ionization of Aligned CH3I Molecules. J Phys Chem A 2017; 121:6547-6553. [DOI: 10.1021/acs.jpca.7b05588] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Sizuo Luo
- Institute of Atomic
and Molecular Physics, and Jilin Provincial
Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jilin University, Changchun 130012, China
| | - Wenhui Hu
- Institute of Atomic
and Molecular Physics, and Jilin Provincial
Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jilin University, Changchun 130012, China
| | - Jiaqi Yu
- Institute of Atomic
and Molecular Physics, and Jilin Provincial
Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jilin University, Changchun 130012, China
| | - Xiaokai Li
- Institute of Atomic
and Molecular Physics, and Jilin Provincial
Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jilin University, Changchun 130012, China
| | - Lanhai He
- Institute of Atomic
and Molecular Physics, and Jilin Provincial
Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jilin University, Changchun 130012, China
| | - Chuncheng Wang
- Institute of Atomic
and Molecular Physics, and Jilin Provincial
Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jilin University, Changchun 130012, China
| | - Fuchun Liu
- Institute of Atomic
and Molecular Physics, and Jilin Provincial
Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jilin University, Changchun 130012, China
| | - Dajun Ding
- Institute of Atomic
and Molecular Physics, and Jilin Provincial
Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jilin University, Changchun 130012, China
| |
Collapse
|
11
|
Lackner F, Chatterley AS, Pemmaraju CD, Closser KD, Prendergast D, Neumark DM, Leone SR, Gessner O. Direct observation of ring-opening dynamics in strong-field ionized selenophene using femtosecond inner-shell absorption spectroscopy. J Chem Phys 2017; 145:234313. [PMID: 28010094 DOI: 10.1063/1.4972258] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Femtosecond extreme ultraviolet transient absorption spectroscopy is used to explore strong-field ionization induced dynamics in selenophene (C4H4Se). The dynamics are monitored in real-time from the viewpoint of the Se atom by recording the temporal evolution of element-specific spectral features near the Se 3d inner-shell absorption edge (∼58 eV). The interpretation of the experimental results is supported by first-principles time-dependent density functional theory calculations. The experiments simultaneously capture the instantaneous population of stable molecular ions, the emergence and decay of excited cation states, and the appearance of atomic fragments. The experiments reveal, in particular, insight into the strong-field induced ring-opening dynamics in the selenophene cation, which are traced by the emergence of non-cyclic molecules as well as the liberation of Se+ ions within an overall time scale of approximately 170 fs. We propose that both products may be associated with dynamics on the same electronic surfaces but with different degrees of vibrational excitation. The time-dependent inner-shell absorption features provide direct evidence for a complex relaxation mechanism that may be approximated by a two-step model, whereby the initially prepared, excited cyclic cation decays within τ1 = 80 ± 30 fs into a transient molecular species, which then gives rise to the emergence of bare Se+ and ring-open cations within an additional τ2 = 80 ± 30 fs. The combined experimental and theoretical results suggest a close relationship between σ* excited cation states and the observed ring-opening reactions. The findings demonstrate that the combination of femtosecond time-resolved core-level spectroscopy with ab initio estimates of spectroscopic signatures provide new insights into complex, ultrafast photochemical reactions such as ring-opening dynamics in organic molecules in real-time and with simultaneous sensitivity for electronic and structural rearrangements.
Collapse
Affiliation(s)
- Florian Lackner
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Adam S Chatterley
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - C D Pemmaraju
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Kristina D Closser
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - David Prendergast
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Daniel M Neumark
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Stephen R Leone
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Oliver Gessner
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| |
Collapse
|
12
|
Chatterley AS, Lackner F, Pemmaraju CD, Neumark DM, Leone SR, Gessner O. Dissociation Dynamics and Electronic Structures of Highly Excited Ferrocenium Ions Studied by Femtosecond XUV Absorption Spectroscopy. J Phys Chem A 2016; 120:9509-9518. [DOI: 10.1021/acs.jpca.6b09724] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Adam S. Chatterley
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Florian Lackner
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - C. D. Pemmaraju
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Daniel M. Neumark
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Stephen R. Leone
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Oliver Gessner
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| |
Collapse
|
13
|
Leone SR, Neumark DM. Attosecond science in atomic, molecular, and condensed matter physics. Faraday Discuss 2016; 194:15-39. [DOI: 10.1039/c6fd00174b] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Attosecond science represents a new frontier in atomic, molecular, and condensed matter physics, enabling one to probe the exceedingly fast dynamics associated with purely electronic dynamics in a wide range of systems. This paper presents a brief discussion of the technology required to generate attosecond light pulses and gives representative examples of attosecond science carried out in several laboratories. Attosecond transient absorption, a very powerful method in attosecond science, is then reviewed and several examples of gas phase and condensed phase experiments that have been carried out in the Leone/Neumark laboratories are described.
Collapse
Affiliation(s)
- Stephen R. Leone
- Department of Chemistry
- University of California
- Berkeley
- USA
- Department of Physics
| | - Daniel M. Neumark
- Department of Chemistry
- University of California
- Berkeley
- USA
- Chemical Sciences Division
| |
Collapse
|
14
|
Chatterley AS, Lackner F, Neumark DM, Leone SR, Gessner O. Tracking dissociation dynamics of strong-field ionized 1,2-dibromoethane with femtosecond XUV transient absorption spectroscopy. Phys Chem Chem Phys 2016; 18:14644-53. [DOI: 10.1039/c6cp02598f] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Using femtosecond time-resolved extreme ultraviolet absorption spectroscopy, the dissociation dynamics of the haloalkane 1,2-dibromoethane (DBE) have been explored following strong field ionization by femtosecond near infrared pulses at intensities between 7.5 × 1013 and 2.2 × 1014 W cm−2.
Collapse
Affiliation(s)
- Adam S. Chatterley
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Chemistry
| | - Florian Lackner
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Chemistry
| | - Daniel M. Neumark
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Chemistry
| | - Stephen R. Leone
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
- Department of Chemistry
| | - Oliver Gessner
- Chemical Sciences Division
- Lawrence Berkeley National Laboratory
- Berkeley
- USA
| |
Collapse
|
15
|
Attar AR, Piticco L, Leone SR. Core-to-valence spectroscopic detection of the CH2Br radical and element-specific femtosecond photodissociation dynamics of CH2IBr. J Chem Phys 2015; 141:164308. [PMID: 25362300 DOI: 10.1063/1.4898375] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
Abstract
Element-specific single photon photodissociation dynamics of CH2IBr and core-to-valence absorption spectroscopy of CH2Br radicals are investigated using femtosecond high-harmonic extreme ultraviolet (XUV) transient absorption spectroscopy. Photodissociation of CH2IBr along both the C-I or C-Br reaction coordinates is observed in real-time following excitation at 266 nm. At this wavelength, C-I dissociation is the dominant reaction channel and C-Br dissociation is observed as a minor pathway. Both photodissociation pathways are probed simultaneously through individual 4d(I) N(4/5) and 3d(Br) M(4/5) core-to-valence transitions. The 3d(Br) M(4/5) pre-edge absorption spectrum of the CH2Br radical photoproduct corresponding to the C-I dissociation channel is characterized for the first time. Although the radical's singly occupied molecular orbital (SOMO) is mostly localized on the central carbon atom, the 3d(Br) → π*(SOMO) resonances at 68.5 eV and 69.5 eV are detected 2 eV below the parent molecule 3d(Br) → σ*(LUMO) transitions. Core-to-valence XUV absorption spectroscopy provides a unique probe of the local electronic structure of the radical species in reference to the Br reporter atom. The measured times for C-I dissociation leading to I and I* atomic products are 48 ± 12 fs and 44 ± 4 fs, respectively, while the measured C-Br dissociation time leading to atomic Br is 114 ± 17 fs. The investigation performed here demonstrates the capability of femtosecond time-resolved core-level spectroscopy utilizing multiple reporter atoms simultaneously.
Collapse
Affiliation(s)
- Andrew R Attar
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Lorena Piticco
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| | - Stephen R Leone
- Department of Chemistry, University of California, Berkeley, California 94720, USA
| |
Collapse
|
16
|
Timmers H, Li Z, Shivaram N, Santra R, Vendrell O, Sandhu A. Coherent electron hole dynamics near a conical intersection. PHYSICAL REVIEW LETTERS 2014; 113:113003. [PMID: 25259975 DOI: 10.1103/physrevlett.113.113003] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Indexed: 06/03/2023]
Abstract
The coherent evolution of an electron hole in a photoionized molecule represents an unexplored facet of charge transfer phenomena occurring in complex systems. Using ultrafast extreme ultraviolet spectroscopy, we investigate the real-time dynamics of an electron hole wave packet created near a conical intersection in CO_{2}. We resolve the oscillation of the electron hole density between σ and π character, driven by the coupled bending and asymmetric stretch vibrations of the molecule. We also quantify the mixing between electron hole configurations and find that the wave packet coherence diminishes with time due to thermal dephasing.
Collapse
Affiliation(s)
- Henry Timmers
- Department of Physics, University of Arizona, Tucson, Arizona 85721, USA
| | - Zheng Li
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, D-22607 Hamburg, Germany and Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - Niranjan Shivaram
- Department of Physics, University of Arizona, Tucson, Arizona 85721, USA
| | - Robin Santra
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, D-22607 Hamburg, Germany and Department of Physics, University of Hamburg, D-20355 Hamburg, Germany
| | - Oriol Vendrell
- Center for Free-Electron Laser Science, DESY, Notkestrasse 85, D-22607 Hamburg, Germany
| | - Arvinder Sandhu
- Department of Physics, University of Arizona, Tucson, Arizona 85721, USA
| |
Collapse
|
17
|
Affiliation(s)
- Majed Chergui
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC, FSB, Station 6, CH-1015 Lausanne, Switzerland.
| |
Collapse
|