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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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2
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Liu Y, Rozgonyi T, Marquetand P, Weinacht T. Excited-state dynamics of CH 2I 2 and CH 2IBr studied with UV-pump VUV-probe momentum-resolved photoion spectroscopy. J Chem Phys 2020; 153:184304. [PMID: 33187419 DOI: 10.1063/5.0026177] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We perform time-resolved ionization spectroscopy measurements of the excited state dynamics of CH2I2 and CH2IBr following photoexcitation in the deep UV. The fragment ions produced by ionization with a vacuum-ultraviolet probe pulse are measured with velocity map imaging, and the momentum resolved yields are compared with trajectory surface hopping calculations of the measurement observable. Together with recent time-resolved photoelectron spectroscopy measurements of the same dynamics, these results provide a detailed picture of the coupled electronic and nuclear dynamics involved. Our measurements highlight the non-adiabatic coupling between electronic states, which leads to notable differences in the dissociation dynamics for the two molecules.
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Affiliation(s)
- Yusong Liu
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA
| | - Tamás Rozgonyi
- Wigner Research Centre for Physics, P.O. Box 49, H-1525 Budapest, Hungary
| | - Philipp Marquetand
- University of Vienna, Faculty of Chemistry, Institute of Theoretical Chemistry, Währinger Straße 17, 1090 Wien, Austria
| | - Thomas Weinacht
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, USA
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3
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Marggi Poullain S, Chicharro DV, Zanchet A, Rubio-Lago L, García-Vela A, Bañares L. The 3s versus 3p Rydberg state photodissociation dynamics of the ethyl radical. Phys Chem Chem Phys 2019; 21:23017-23025. [PMID: 31599893 DOI: 10.1039/c9cp04273c] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The photodissociation dynamics of the ethyl radical following excitation into the 3s and 3p Rydberg states are revisited in a joint experimental and theoretical study. Two different methods to produce the ethyl radical, pyrolysis and in situ photolysis, are employed in order to modify the initial ro-vibrational energy distribution characterizing the ethyl radical beam. H-atom velocity map images following excitation of the radical at 243 nm and at 201 nm are presented and discussed along with ab initio potential energy curves focussing on the bridged C2v geometry. The reported results show that the dynamics following excitation to the 3s Rydberg state is insensitive to the initial internal energy of the parent radical, in contrast to the dynamics on the 3p Rydberg state, which is strongly modified. The role of the bridged C2v geometry on both photodynamics is highlighted and discussed.
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Affiliation(s)
- Sonia Marggi Poullain
- Departamento de Química, Módulo 13, Facultad de Ciencias, Universidad Autónoma de Madrid, 28049 Madrid, Spain
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4
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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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5
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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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6
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Corrales ME, González-Vázquez J, de Nalda R, Bañares L. Coulomb Explosion Imaging for the Visualization of a Conical Intersection. J Phys Chem Lett 2019; 10:138-143. [PMID: 30561209 DOI: 10.1021/acs.jpclett.8b03726] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Coulomb explosion imaging is proposed as a method to directly map the presence of conical intersections encountered by a propagating wave packet in a molecular system. The case of choice is the nonadiabatic coupling between two dissociative surfaces in the methyl iodide molecule, probed by Coulomb explosion with short, intense near-infrared pulses causing multiple ionization. On-the-fly multidimensional trajectory calculations with surface hopping using perturbation theory and including spin-orbit coupling are performed to visualize the dynamics through the conical intersection and compare with experimental results. The possibilities and limitations of the technique are examined and discussed.
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Affiliation(s)
- M E Corrales
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC) , Facultad de Ciencias Químicas, Universidad Complutense de Madrid , 28040 Madrid , Spain
- Centro de Láseres Ultrarrápidos , Facultad de Ciencias Químicas, Universidad Complutense de Madrid , 28040 Madrid , Spain
| | - J González-Vázquez
- Departamento de Química and Institute for Advanced Research in Chemical Sciences (IAdChem), Módulo 13 , Facultad de Ciencias, Universidad Autónoma de Madrid , 28049 Madrid , Spain
| | - R de Nalda
- Instituto de Química Física Rocasolano, CSIC , C/Serrano 119 , 28006 Madrid , Spain
| | - L Bañares
- Departamento de Química Física (Unidad Asociada I+D+i al CSIC) , Facultad de Ciencias Químicas, Universidad Complutense de Madrid , 28040 Madrid , Spain
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7
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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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8
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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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