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Schaffner D, Juncker von Buchwald T, Karaev E, Alagia M, Richter R, Stranges S, Coriani S, Fischer I. The x-ray absorption spectrum of the tert-butyl radical: An experimental and computational investigation. J Chem Phys 2024; 161:034309. [PMID: 39017428 DOI: 10.1063/5.0216364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 06/16/2024] [Indexed: 07/18/2024] Open
Abstract
We report the x-ray absorption spectrum (XAS) of the tert-butyl radical, C4H9. The radical was generated pyrolytically from azo-tert-butane, and the XAS of the pure radical was obtained by subtraction of spectra recorded at different temperatures. The bands in the XAS were assigned by ab initio calculations that are in very good agreement with the experimental data. The lowest energy signal in the XAS is assigned to the C1s electron transition from the central carbon atom to the singly occupied molecular orbital (SOMO), while higher transitions correspond to C1s excitations from terminal carbon atoms. Furthermore, we investigated the fragmentation of the radical following resonant C1s excitation by electron-ion-coincidence spectroscopy. Several fragmentation channels were identified. The C1s excitation of the terminal carbons is associated with a stronger fragmentation tendency compared to the lowest C1s excitation of the central carbon into the SOMO. For this core excited state, we still observe an intact parent ion, C4H9+, and a comparatively higher tendency to dissociate into CH3+ + C3H6+.
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Affiliation(s)
- Dorothee Schaffner
- Institute of Physical and Theoretical Chemistry, University of Würzburg, D-97074 Würzburg, Germany
| | | | - Emil Karaev
- Institute of Physical and Theoretical Chemistry, University of Würzburg, D-97074 Würzburg, Germany
| | - Michele Alagia
- CNR-Istituto Officina dei Materiali (IOM), Laboratorio TASC, 34149 Trieste, Italy
| | - Robert Richter
- Elettra-Sincrotrone Trieste, Area Science Park, I-34149 Basovizza, Trieste, Italy
| | - Stefano Stranges
- CNR-Istituto Officina dei Materiali (IOM), Laboratorio TASC, I-34149 Trieste, Italy
- Dipartimento di Chimica e Tecnologia dei Farmaci, Università degli Studi di Roma "La Sapienza," Piazzale Aldo Moro 5, I-00185 Rome, Italy
| | - Sonia Coriani
- DTU Chemistry, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Ingo Fischer
- Institute of Physical and Theoretical Chemistry, University of Würzburg, D-97074 Würzburg, Germany
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2
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Zhang Y, Zang L, Zhao S, Cheng W, Zhang L, Sun L. Brominated metal phthalocyanine-based covalent organic framework for enhanced selective photocatalytic reduction of CO 2. J Colloid Interface Sci 2024; 655:1-11. [PMID: 37924586 DOI: 10.1016/j.jcis.2023.10.111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2023] [Revised: 10/17/2023] [Accepted: 10/21/2023] [Indexed: 11/06/2023]
Abstract
Covalent organic frameworks (COFs) have great potential for photocatalytic CO2 reduction, owing to their adjustable structures, porous characteristics, and highly ordered nature. However, poor light absorption, fast recombination of photogenerated electron-hole pairs, and suboptimal coordination conditions have contributed to the hindered efficiency and selectivity observed in photocatalytic CO2 reduction processes. In this work, the integration of bromine (Br) atoms into COFs was achieved through the synthesis process involving nickel (II) tetraaminophthalocyanine (NiTAPc) and 3,6-dibromopyromellitic dianhydride (BPMDA) using a solvothermal approach. The coupling of a porous framework structure alongside the incorporation of Br atoms yields a significant enhancement in photoelectric properties compared to bromine-free COFs. Meanwhile, X-ray photoelectron spectroscopy (XPS) and density functional theory (DFT) calculations revealed that the introduction of Br atoms can facilitate the adjustment of the electron configuration around the phthalocyanine unit and diminish the required energy for the photocatalytic reaction. When subjected to visible light irradiation, the NiTAPc-BPMDA COF showcased a CO yield of 148.25 μmol g-1 over a 5-hour period, accompanied by an impressive selectivity of 98%. This work highlights the collaborative influence of phthalocyanines and Br atoms within COF-based photocatalysts, offering an alternative approach for designing and constructing high-performance photocatalysts with elevated yield and selectivity. The synergistic role of phthalocyanines and Br atoms within the COF-based photocatalysts provides an alternative strategy for photocatalysts with high yield and selectivity in the future.
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Affiliation(s)
- Ying Zhang
- School of Chemical Engineering and Materials, Heilongjiang University, Harbin 150080, PR China
| | - Linlin Zang
- School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212000, PR China.
| | - Shuting Zhao
- School of Chemistry and Environmental Engineering, Changchun University of Science and Technology, Changchun 130022, PR China
| | - Weipeng Cheng
- School of Chemical Engineering and Materials, Heilongjiang University, Harbin 150080, PR China
| | - Long Zhang
- School of Chemical Engineering and Materials, Heilongjiang University, Harbin 150080, PR China
| | - Liguo Sun
- School of Chemical Engineering and Materials, Heilongjiang University, Harbin 150080, PR China.
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3
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Recio P, Cachón J, Rubio-Lago L, Chicharro DV, Zanchet A, Limão-Vieira P, de Oliveira N, Samartzis PC, Marggi Poullain S, Bañares L. Imaging the Photodissociation Dynamics and Fragment Alignment of CH 2BrI at 193 nm. J Phys Chem A 2022; 126:8404-8422. [DOI: 10.1021/acs.jpca.2c05897] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Affiliation(s)
- Pedro Recio
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040Madrid, Spain
| | - Javier Cachón
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040Madrid, Spain
| | - Luis Rubio-Lago
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040Madrid, Spain
| | - David V. Chicharro
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040Madrid, Spain
- Quantum Dynamics & Control, Max Planck Institute for Nuclear Physics (MPIK), Saupfercheckweg 1, 69117Heidelberg, Germany
| | - Alexandre Zanchet
- Instituto de Física Fundamental, Consejo Superior de Investigaciones Científicas, Serrano 123, 28006Madrid, Spain
| | - Paulo Limão-Vieira
- Atomic and Molecular Collisions Laboratory, CEFITEC, Department of Physics, Universidade NOVA de Lisboa, 2829-516Caparica, Portugal
| | - Nelson de Oliveira
- Synchrotron SOLEIL, L’Orme des Merisiers, St. Aubin, BP 48, 91192Gif sur Yvette, France
| | - Peter C. Samartzis
- Institute of Electronic Structure and Laser, Foundation for Research and Technology-Hellas (FORTH-IESL), Vassilika Vouton, 70013Heraklion, Greece
| | - Sonia Marggi Poullain
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040Madrid, Spain
| | - Luis Bañares
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC), Facultad de Ciencias Químicas, Universidad Complutense de Madrid, 28040Madrid, Spain
- Instituto Madrileño de Estudios Avanzados en Nanociencia (IMDEA-Nanoscience), Cantoblanco, 28049Madrid, Spain
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4
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Che DC, Kawamata H, Nakamura M, Kasai T, Lin KC. A vector correlation study using a hexapole-oriented molecular beam: photodissociation dynamics of oriented isohaloethane. Phys Chem Chem Phys 2022; 24:5914-5920. [PMID: 35195628 DOI: 10.1039/d1cp05788j] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The photodissociation dynamics of isohaloethane (1-bromo-2-chloro-1,1,2-trifluoroethane) at 234 nm was studied by a sliced imaging technique combined with an oriented molecular beam. The speed and angular distributions of the competitive products of spin-orbit selected Br and Cl atoms were determined by analysis of the obtained images. The anisotropic parameter, β, was found to be 2.0 ± 0.2 for the excited state of Br(2P1/2) (Br*) and 1.2 ± 0.3 for the ground state of Br(2P3/2) (Br). The speed distributions for both Br and Br* exhibited Gaussian-like characteristics. These results indicate that Br atoms were generated by direct formation after excitation through the nσ*(C-Br) potential energy surfaces. In contrast, the angular distributions for the Cl fragments were almost isotropic, while the speed distributions displayed Boltzmann-like characteristics. This suggests that the Cl atoms may form through long-lived parent molecules after photoexcitation. The branching ratio for Br and Cl atom formation was found to be approximately 1.2, that is, Br atom formation occurred preferentially, in contrast to the case of halothane photodissociation reported in our previous work [Che et al., J. Phys. Chem. A, 2020, 124, 5288]. A vector correlation study between the laser polarization axis and the direction of the dipole moment revealed a similar tendency for all photofragments, suggesting that the fragments were formed through a common excited state of isohaloethane. The vector correlation was also studied theoretically for comparison with the experimental results. The angle between the transition dipole moment in photodissociation and the permanent dipole moment was found to be 42 ± 15°. The obtained results indicate that this vector correlation approach combined with an oriented molecular beam is a powerful tool for determining the transition dipole moments in photodissociation.
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Affiliation(s)
- Dock-Chil Che
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan.
| | - Hiroshi Kawamata
- Center for Higher Education and Global Admissions, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Masaaki Nakamura
- Department of Chemistry, School of Science, Tokyo Institute of Technology, Meguro, Tokyo 152-8550, Japan
| | - Toshio Kasai
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan.,Department of Applied Physics, Osaka University, Suita, Osaka 565-0871, Japan
| | - King-Chuen Lin
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan.,Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
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5
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Chen M, Lopata K. First-Principles Simulations of X-ray Transient Absorption for Probing Attosecond Electron Dynamics. J Chem Theory Comput 2020; 16:4470-4478. [PMID: 32470295 PMCID: PMC7467644 DOI: 10.1021/acs.jctc.0c00122] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
X-ray transient absorption spectroscopy (XTAS) is a promising technique for measuring electron dynamics in molecules and solids with attosecond time resolutions. In XTAS, the elemental specificity and spatial locality of core-to-valence X-ray absorption is exploited to relate modulations in the time-resolved absorption spectra to local electron density variations around particular atoms. However, interpreting these absorption modulations and frequency shifts as a function of the time delay in terms of dynamics can be challenging. In this paper, we present a first-principles study of attosecond XTAS in a selection of simple molecules based on real-time time-dependent density functional theory (RT-TDDFT) with constrained DFT to emulate the state of the system following the interaction with a ultraviolet pump laser. In general, there is a decrease in the optical density and a blue shift in the frequency with increasing electron density around the absorbing atom. In carbon monoxide (CO), modulations in the O K-edge occur at the frequency of the valence electron dynamics, while for dioxygen (O2) they occur at twice the frequency, due to the indistinguishability of the oxygen atoms. In 4-aminophenol (H2NC6H4OH), likewise, there is a decrease in the optical density and a blue shift in the frequency for the oxygen and nitrogen K-edges with increasing charge density on the O and N, respectively. Similar effects are observed in the nitrogen K-edge for a long-range charge-transfer excitation in a benzene (C6H6)-tetracyanoethylene (C6N4; TCNE) dimer but with weaker modulations due to the delocalization of the charge across the entire TCNE molecule. Additionally, in all cases, there are pre-edge features corresponding to core transitions to depopulated orbitals. These potentially offer a background-free signal that only appears in pumped molecules.
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Affiliation(s)
- Min Chen
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States
| | - Kenneth Lopata
- Department of Chemistry, Louisiana State University, Baton Rouge, Louisiana 70803, United States.,Center for Computation and Technology, Louisiana State University, Baton Rouge, Louisiana 70803, United States
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6
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Che DC, Nakamura M, Chang HP, Lin KC, Kasai T, Aquilanti V, Palazzetti F. UV Photodissociation of Halothane in a Focused Molecular Beam: Space-Speed Slice Imaging of Competitive Bond Breaking into Spin-Orbit-Selected Chlorine and Bromine Atoms. J Phys Chem A 2020; 124:5288-5296. [PMID: 32498517 DOI: 10.1021/acs.jpca.0c02800] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A molecular beam of halothane (2-bromo-2-chloro-1,1,1-trifluoroethane) is focused by a hexapolar electrostatic field and photolyzed by UV laser radiation at 234 nm. Angular and speed distributions of chlorine and bromine photofragments emitted from halothane are measured for both spin-orbit states independently. Although the dissociation energy of the C-Cl bond is larger than that of C-Br, the relative yield of Cl to Br was found to be approximately 2. Measured speed and angular distributions of atomic fragments show distinct kinetic energy release and scattering characteristics: for bromine, observed fast and aligned fragments exhibit a signature of a direct mode of dissociation for the C-Br bond, via the electronically excited potential energy surface denoted nσ*(C-Br), of repulsive nature; for chlorine, a variation in the features is observed for the dissociation pathway through nσ*(C-Cl), from a modality similar to the bromine case, leading to fragments with appreciable kinetic energy release and pronounced directionality, to a modality involving slow products, nearly isotopically distributed. The origin of this behavior can be attributed to nonadiabatic interaction operating between the nσ*(C-Br) and nσ*(C-Cl) surfaces. These results are not only relevant for a detailed understanding of adiabatic versus diabatic coupling mechanisms in the manifold of excited states populated by photon absorption, but they also point out the possibility of selectively inducing specific dissociation pathways, even when involving energetically unfavorable outcomes, such as, in this case, the prevailing rupture of the stronger C-Cl bond against that of the weaker C-Br bond.
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Affiliation(s)
- Dock-Chil Che
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043, Japan
| | - Masaaki Nakamura
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - Hsiu-Pu Chang
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan
| | - King-Chuen Lin
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan.,Institute of Atomic and Molecular Sciences, Academia Sinica, Taipei 10617, Taiwan
| | - Toshio Kasai
- Department of Chemistry, National Taiwan University, Taipei 10617, Taiwan.,Institute of Scientific and Industrial Research, Osaka University, Ibaraki, Osaka 567-0047, Japan
| | - Vincenzo Aquilanti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Perugia 06123, Italy.,Istituto di Struttura della Materia, Consiglio Nazionale delle Ricerche, Rome 00016, Italy
| | - Federico Palazzetti
- Dipartimento di Chimica, Biologia e Biotecnologie, Università di Perugia, Perugia 06123, Italy
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7
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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.
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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
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8
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Toulson BW, Borgwardt M, Wang H, Lackner F, Chatterley AS, Pemmaraju CD, Neumark DM, Leone SR, Prendergast D, Gessner O. Probing ultrafast C-Br bond fission in the UV photochemistry of bromoform with core-to-valence transient absorption spectroscopy. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2019; 6:054304. [PMID: 31649963 PMCID: PMC6800284 DOI: 10.1063/1.5113798] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/07/2019] [Accepted: 09/12/2019] [Indexed: 06/10/2023]
Abstract
UV pump-extreme UV (XUV) probe femtosecond transient absorption spectroscopy is used to study the 268 nm induced photodissociation dynamics of bromoform (CHBr3). Core-to-valence transitions at the Br(3d) absorption edge (∼70 eV) provide an atomic scale perspective of the reaction, sensitive to changes in the local valence electronic structure, with ultrafast time resolution. The XUV spectra track how the singly occupied molecular orbitals of transient electronic states develop throughout the C-Br bond fission, eventually forming radical Br and CHBr2 products. Complementary ab initio calculations of XUV spectral fingerprints are performed for transient atomic arrangements obtained from sampling excited-state molecular dynamics simulations. C-Br fission along an approximately C S symmetrical reaction pathway leads to a continuous change of electronic orbital characters and atomic arrangements. Two timescales dominate changes in the transient absorption spectra, reflecting the different characteristic motions of the light C and H atoms and the heavy Br atoms. Within the first 40 fs, distortion from C 3 v symmetry to form a quasiplanar CHBr2 by the displacement of the (light) CH moiety causes significant changes to the valence electronic structure. Displacement of the (heavy) Br atoms is delayed and requires up to ∼300 fs to form separate Br + CHBr2 products. We demonstrate that transitions between the valence-excited (initial) and valence + core-excited (final) state electronic configurations produced by XUV absorption are sensitive to the localization of valence orbitals during bond fission. The change in valence electron-core hole interaction provides a physical explanation for spectral shifts during the process of bond cleavage.
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Affiliation(s)
- Benjamin W. Toulson
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Mario Borgwardt
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Han Wang
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | | | | | - C. D. Pemmaraju
- Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory, Stanford, California 94025, USA
| | | | | | | | - Oliver Gessner
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
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9
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Muthiah B, Paredes-Roibás D, Kasai T, Lin KC. Photodissociation of CH 2BrI using cavity ring-down spectroscopy: in search of a BrI elimination channel. Phys Chem Chem Phys 2019; 21:13943-13949. [PMID: 30137071 DOI: 10.1039/c8cp04130j] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photodissociation of CH2BrI was investigated in search of unimolecular elimination of BrI via a primary channel using cavity ring-down absorption spectroscopy (CRDS) at 248 nm. The BrI spectra were acquired involving the first three ground vibrational levels corresponding to A3Π1 ← X1Σ+ transition. With the aid of spectral simulation, the BrI rotational lines were assigned. The nascent vibrational populations for v'' = 0, 1, and 2 levels are obtained with a population ratio of 1 : (0.58 ± 0.10) : (0.34 ± 0.05), corresponding to a Boltzmann-like vibrational temperature of 713 ± 49 K. The quantum yield of the ground state BrI elimination reaction is determined to be 0.044 ± 0.014. The CCSD(T)//B3LYP/MIDI! method was employed to explore the potential energy surface for the unimolecular elimination of BrI from CH2BrI.
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Affiliation(s)
- Balaganesh Muthiah
- Department of Chemistry, National Taiwan Univeristy, Taipei 106, Taiwan.
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10
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Geneaux R, Marroux HJB, Guggenmos A, Neumark DM, Leone SR. Transient absorption spectroscopy using high harmonic generation: a review of ultrafast X-ray dynamics in molecules and solids. PHILOSOPHICAL TRANSACTIONS. SERIES A, MATHEMATICAL, PHYSICAL, AND ENGINEERING SCIENCES 2019; 377:20170463. [PMID: 30929624 PMCID: PMC6452051 DOI: 10.1098/rsta.2017.0463] [Citation(s) in RCA: 75] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 11/27/2018] [Indexed: 05/07/2023]
Abstract
Attosecond science opened the door to observing nuclear and electronic dynamics in real time and has begun to expand beyond its traditional grounds. Among several spectroscopic techniques, X-ray transient absorption spectroscopy has become key in understanding matter on ultrafast time scales. In this review, we illustrate the capabilities of this unique tool through a number of iconic experiments. We outline how coherent broadband X-ray radiation, emitted in high-harmonic generation, can be used to follow dynamics in increasingly complex systems. Experiments performed in both molecules and solids are discussed at length, on time scales ranging from attoseconds to picoseconds, and in perturbative or strong-field excitation regimes. This article is part of the theme issue 'Measurement of ultrafast electronic and structural dynamics with X-rays'.
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Affiliation(s)
- Romain Geneaux
- Department of Chemistry, University of California, Berkeley 94720, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, CA, USA
| | - Hugo J. B. Marroux
- Department of Chemistry, University of California, Berkeley 94720, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, CA, USA
| | - Alexander Guggenmos
- Department of Chemistry, University of California, Berkeley 94720, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, CA, USA
| | - Daniel M. Neumark
- Department of Chemistry, University of California, Berkeley 94720, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, CA, USA
| | - Stephen R. Leone
- Department of Chemistry, University of California, Berkeley 94720, CA, USA
- Department of Physics, University of California, Berkeley 94720, CA, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley 94720, CA, USA
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11
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Horton SL, Liu Y, Forbes R, Makhija V, Lausten R, Stolow A, Hockett P, Marquetand P, Rozgonyi T, Weinacht T. Excited state dynamics of CH 2I 2 and CH 2BrI studied with UV pump VUV probe photoelectron spectroscopy. J Chem Phys 2019; 150:174201. [PMID: 31067867 DOI: 10.1063/1.5086665] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
We compare the excited state dynamics of diiodomethane (CH2I2) and bromoiodomethane (CH2BrI) using time resolved photoelectron spectroscopy. A 4.65 eV UV pump pulse launches a dissociative wave packet on excited states of both molecules and the ensuing dynamics are probed via photoionization using a 7.75 eV probe pulse. The resulting photoelectrons are measured with the velocity map imaging technique for each pump-probe delay. Our measurements highlight differences in the dynamics for the two molecules, which are interpreted with high-level ab initio molecular dynamics (trajectory surface hopping) calculations. Our analysis allows us to associate features in the photoelectron spectrum with different portions of the excited state wave packet represented by different trajectories. The excited state dynamics in bromoiodomethane are simple and can be described in terms of direct dissociation along the C-I coordinate, whereas the dynamics in diiodomethane involve internal conversion and motion along multiple dimensions.
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Affiliation(s)
- Spencer L Horton
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA
| | - Yusong Liu
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA
| | - Ruaridh Forbes
- Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada
| | - Varun Makhija
- Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada
| | - Rune Lausten
- National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Albert Stolow
- Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada
| | - Paul Hockett
- National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Philipp Marquetand
- Faculty of Chemistry, Institute of Theoretical Chemistry, University of Vienna, Währinger Str. 17, 1090 Wien, Austria
| | - Tamás Rozgonyi
- Institute of Materials and Environmental Chemistry, Research Centre for Natural Sciences, Hungarian Academy of Sciences, Magyar Tudósok Körútja 2, Budapest 1117, Hungary
| | - Thomas Weinacht
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA
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12
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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.
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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
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13
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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.
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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
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14
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Yang Z, Schnorr K, Bhattacherjee A, Lefebvre PL, Epshtein M, Xue T, Stanton JF, Leone SR. Electron-Withdrawing Effects in the Photodissociation of CH2ICl To Form CH2Cl Radical, Simultaneously Viewed Through the Carbon K and Chlorine L2,3 X-ray Edges. J Am Chem Soc 2018; 140:13360-13366. [DOI: 10.1021/jacs.8b08303] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Affiliation(s)
- Zheyue Yang
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Kirsten Schnorr
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Aditi Bhattacherjee
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Pierre-Louis Lefebvre
- Quantum Theory Project, Departments of Chemistry and Physics, University of Florida, Gainesville, Florida 32611, United States
| | - Michael Epshtein
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Tian Xue
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - John F. Stanton
- Quantum Theory Project, Departments of Chemistry and Physics, University of Florida, Gainesville, Florida 32611, United States
| | - Stephen R. Leone
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department of Physics, University of California, Berkeley, California 94720, United States
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15
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Bhattacherjee A, Schnorr K, Oesterling S, Yang Z, Xue T, de Vivie-Riedle R, Leone SR. Photoinduced Heterocyclic Ring Opening of Furfural: Distinct Open-Chain Product Identification by Ultrafast X-ray Transient Absorption Spectroscopy. J Am Chem Soc 2018; 140:12538-12544. [DOI: 10.1021/jacs.8b07155] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Affiliation(s)
- Aditi Bhattacherjee
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Kirsten Schnorr
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Sven Oesterling
- Department of Chemistry, Ludwig-Maximilians-Universität München, München 81377, Germany
| | - Zheyue Yang
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Tian Xue
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | | | - Stephen R. Leone
- Department of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department of Physics, University of California, Berkeley, California 94720, United States
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16
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Marcellini M, Nasedkin A, Zietz B, Petersson J, Vincent J, Palazzetti F, Malmerberg E, Kong Q, Wulff M, van der Spoel D, Neutze R, Davidsson J. Transient isomers in the photodissociation of bromoiodomethane. J Chem Phys 2018; 148:134307. [PMID: 29626862 DOI: 10.1063/1.5005595] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
The photochemistry of halomethanes is fascinating for the complex cascade reactions toward either the parent or newly synthesized molecules. Here, we address the structural rearrangement of photodissociated CH2IBr in methanol and cyclohexane, probed by time-resolved X-ray scattering in liquid solution. Upon selective laser cleavage of the C-I bond, we follow the reaction cascade of the two geminate geometrical isomers, CH2I-Br and CH2Br-I. Both meta-stable isomers decay on different time scales, mediated by solvent interaction, toward the original parent molecule. We observe the internal rearrangement of CH2Br-I to CH2I-Br in cyclohexane by extending the time window up to 3 μs. We track the photoproduct kinetics of CH2Br-I in methanol solution where only one isomer is observed. The effect of the polarity of solvent on the geminate recombination pathways is discussed.
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Affiliation(s)
- Moreno Marcellini
- Department of Chemistry-Ångström Laboratory, Uppsala University, P.O. Box 462, SE-751 20 Uppsala, Sweden
| | - Alexandr Nasedkin
- Department of Chemistry-Ångström Laboratory, Uppsala University, P.O. Box 462, SE-751 20 Uppsala, Sweden
| | - Burkhard Zietz
- Department of Chemistry-Ångström Laboratory, Uppsala University, P.O. Box 462, SE-751 20 Uppsala, Sweden
| | - Jonas Petersson
- Department of Chemistry-Ångström Laboratory, Uppsala University, P.O. Box 462, SE-751 20 Uppsala, Sweden
| | - Jonathan Vincent
- Department of Chemistry-Ångström Laboratory, Uppsala University, P.O. Box 462, SE-751 20 Uppsala, Sweden
| | - Federico Palazzetti
- Universitá di Perugia, Dipartimento di Chimica, Biologia e Biotecnologie, 06123 Perugia, Italy
| | - Erik Malmerberg
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-405 30 Gothenburg, Sweden
| | - Qingyu Kong
- Argonne National Laboratory's, Xray Science Division, 9700 S Cass Ave., Argonne, Illinois 60439, USA
| | - Michael Wulff
- European Synchrotron Radiation Facility, B.P. 220, F-380 43 Grenoble Cedex, France
| | - David van der Spoel
- Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, P.O. Box 596, SE-751 24 Uppsala, Sweden
| | - Richard Neutze
- Department of Chemistry and Molecular Biology, University of Gothenburg, SE-405 30 Gothenburg, Sweden
| | - Jan Davidsson
- Department of Chemistry-Ångström Laboratory, Uppsala University, P.O. Box 462, SE-751 20 Uppsala, Sweden
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17
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Pan C, Zhang Y, Lee JD, Kidwell NM. Imaging the Dynamics of CH2BrI Photodissociation in the Near Ultraviolet Region. J Phys Chem A 2018; 122:3728-3734. [PMID: 29600858 DOI: 10.1021/acs.jpca.7b12268] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Changen Pan
- Department of Chemistry, The College of William and Mary, Williamsburg, Virginia 23187-8795, United States
| | - Yi Zhang
- Department of Chemistry, The College of William and Mary, Williamsburg, Virginia 23187-8795, United States
| | - Joseph D. Lee
- Department of Chemistry, The College of William and Mary, Williamsburg, Virginia 23187-8795, United States
| | - Nathanael M. Kidwell
- Department of Chemistry, The College of William and Mary, Williamsburg, Virginia 23187-8795, United States
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18
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Murillo-Sánchez ML, Marggi Poullain S, Bajo JJ, Corrales ME, González-Vázquez J, Solá IR, Bañares L. Halogen-atom effect on the ultrafast photodissociation dynamics of the dihalomethanes CH2ICl and CH2BrI. Phys Chem Chem Phys 2018; 20:20766-20778. [PMID: 30020280 DOI: 10.1039/c8cp03600d] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Real time photodissociation of dihalomethanes has been measured by femtosecond velocity map imaging to disentangle the effect of the halogen-atom on the carbon–iodine cleavage dynamics.
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Affiliation(s)
- Marta L. Murillo-Sánchez
- Departamento de Química Física
- Facultad de Ciencias Químicas
- Universidad Complutense de Madrid
- 28040 Madrid
- Spain
| | - Sonia Marggi Poullain
- Departamento de Química
- Módulo 13
- Facultad de Ciencias
- Universidad Autónoma de Madrid
- 28049 Madrid
| | - Juan J. Bajo
- Departamento de Química Física
- Facultad de Ciencias Químicas
- Universidad Complutense de Madrid
- 28040 Madrid
- Spain
| | - María E. Corrales
- Departamento de Química Física
- Facultad de Ciencias Químicas
- Universidad Complutense de Madrid
- 28040 Madrid
- Spain
| | - Jesús González-Vázquez
- Departamento de Química
- Módulo 13
- Facultad de Ciencias
- Universidad Autónoma de Madrid
- 28049 Madrid
| | - Ignacio R. Solá
- Departamento de Química Física
- Facultad de Ciencias Químicas
- Universidad Complutense de Madrid
- 28040 Madrid
- Spain
| | - Luis Bañares
- Departamento de Química Física
- Facultad de Ciencias Químicas
- Universidad Complutense de Madrid
- 28040 Madrid
- Spain
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19
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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.
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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
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20
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Attar AR, Bhattacherjee A, Pemmaraju CD, Schnorr K, Closser KD, Prendergast D, Leone SR. Femtosecond x-ray spectroscopy of an electrocyclic ring-opening reaction. Science 2017; 356:54-59. [PMID: 28386006 DOI: 10.1126/science.aaj2198] [Citation(s) in RCA: 181] [Impact Index Per Article: 25.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Revised: 01/24/2017] [Accepted: 02/22/2017] [Indexed: 01/30/2023]
Abstract
The ultrafast light-activated electrocyclic ring-opening reaction of 1,3-cyclohexadiene is a fundamental prototype of photochemical pericyclic reactions. Generally, these reactions are thought to proceed through an intermediate excited-state minimum (the so-called pericyclic minimum), which leads to isomerization via nonadiabatic relaxation to the ground state of the photoproduct. Here, we used femtosecond (fs) soft x-ray spectroscopy near the carbon K-edge (~284 electron volts) on a tabletop apparatus to directly reveal the valence electronic structure of this transient intermediate state. The core-to-valence spectroscopic signature of the pericyclic minimum observed in the experiment was characterized, in combination with time-dependent density functional theory calculations, to reveal overlap and mixing of the frontier valence orbital energy levels. We show that this transient valence electronic structure arises within 60 ± 20 fs after ultraviolet photoexcitation and decays with a time constant of 110 ± 60 fs.
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Affiliation(s)
- Andrew R Attar
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Aditi Bhattacherjee
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - C D Pemmaraju
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.,Theory Institute for Materials and Energy Spectroscopies, SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Kirsten Schnorr
- Department of Chemistry, University of California, Berkeley, CA 94720, USA.,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Kristina D Closser
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - David Prendergast
- The Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Stephen R Leone
- Department of Chemistry, University of California, Berkeley, CA 94720, USA. .,Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA.,Department of Physics, University of California, Berkeley, CA 94720, USA
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21
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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
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22
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Drescher L, Galbraith MCE, Reitsma G, Dura J, Zhavoronkov N, Patchkovskii S, Vrakking MJJ, Mikosch J. Communication: XUV transient absorption spectroscopy of iodomethane and iodobenzene photodissociation. J Chem Phys 2016; 145:011101. [DOI: 10.1063/1.4955212] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
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23
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Bhattacherjee A, Attar AR, Leone SR. Transition state region in the A-Band photodissociation of allyl iodide—A femtosecond extreme ultraviolet transient absorption study. J Chem Phys 2016; 144:124311. [DOI: 10.1063/1.4944930] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Aditi Bhattacherjee
- Department of Chemistry, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Andrew R. Attar
- Department of Chemistry, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Stephen R. Leone
- Department of Chemistry, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Physics, University of California, Berkeley, California 94720, USA
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24
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Attar AR, Bhattacherjee A, Leone SR. Direct Observation of the Transition-State Region in the Photodissociation of CH3I by Femtosecond Extreme Ultraviolet Transient Absorption Spectroscopy. J Phys Chem Lett 2015; 6:5072-7. [PMID: 26636176 DOI: 10.1021/acs.jpclett.5b02489] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Femtosecond extreme ultraviolet (XUV) pulses produced by high harmonic generation are used to probe the transition-state region in the 266 nm photodissociation of CH3I by the real-time evolution of core-to-valence transitions near the iodine N-edge at 45-60 eV. During C-I bond breaking, new core-to-valence electronic states appear in the spectra, which decay concomitantly with the rise of the atomic iodine resonances of I((2)P3/2) and I*((2)P1/2). The short-lived features are assigned to repulsive valence-excited transition-state regions of (3)Q0 and (1)Q1, which can connect to transient core-excited states via promotion of 4d(I) core electrons. A simplified one-electron transition picture is described that accurately predicts the relative energies of the transient states observed. The transition-state resonances reach a maximum at ∼40 fs and decay to complete C-I dissociation in ∼90 fs, representing the shortest-lived chemical transition state observed by core-level, XUV, or X-ray spectroscopy.
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Affiliation(s)
- Andrew R Attar
- Department of Chemistry, University of California , Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Aditi Bhattacherjee
- Department of Chemistry, University of California , Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Stephen R Leone
- Department of Chemistry, University of California , Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
- Department of Physics, University of California , Berkeley, California 94720, United States
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