1
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Sturm F, Herok C, Fischer I. Non-Radiative Deactivation in Isolated Quinoline. J Phys Chem A 2024. [PMID: 39303210 DOI: 10.1021/acs.jpca.4c04208] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/22/2024]
Abstract
The photophysics of the S2 1(ππ*) state of the polycyclic aromatic nitrogen-containing hydrocarbon (PANH) quinoline is investigated in a free jet using a picosecond laser system. A [1 + 1] multiphoton ionization spectrum yields the S2 origin at around 32 200 cm-1 and reveals several vibronic bands. In time-resolved experiments, quinoline is then excited between 312.2 and 279.7 nm. Probe wavelengths of 351 and 263.5 nm are employed. The dynamics is monitored by time-resolved photoelectron imaging. The images reveal a short-lived band at high electron kinetic energies with a ps lifetime and a band at lower electron kinetic energies that shows an offset at long delay times. In comparison with previous work, the offset is assigned to ionization from the T1 state. Lifetimes decrease from 45 ps at the S2 origin to 11 ps at +3550 cm-1. Most likely, the S2 1(ππ*) state deactivates by internal conversion to the S1 1(nπ*) state, followed by intersystem crossing to the triplet manifold.
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Affiliation(s)
- Floriane Sturm
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Christoph Herok
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany
| | - Ingo Fischer
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany
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2
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Makhija V, Gupta R, Neville S, Schuurman M, Francisco J, Kais S. Time Resolved Quantum Tomography in Molecular Spectroscopy by the Maximal Entropy Approach. J Phys Chem Lett 2024; 15:9525-9534. [PMID: 39264357 DOI: 10.1021/acs.jpclett.4c02368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2024]
Abstract
Attosecond science offers unprecedented precision in probing the initial moments of chemical reactions, revealing the dynamics of molecular electrons that shape reaction pathways. A fundamental question emerges: what role, if any, do quantum coherences between molecular electron states play in photochemical reactions? Answering this question necessitates quantum tomography─the determination of the electronic density matrix from experimental data, where the off-diagonal elements represent these coherences. The Maximal Entropy (MaxEnt) based Quantum State Tomography (QST) approach offers unique advantages in studying molecular dynamics, particularly with partial tomographic data. Here, we explore the application of MaxEnt-based QST on photoexcited ammonia, necessitating the operator form of observables specific to the performed measurements. We present two methodologies for constructing these operators: one leveraging Molecular Angular Distribution Moments (MADMs) which accurately capture the orientation-dependent vibronic dynamics of molecules and another utilizing Angular Momentum Coherence Operators to construct measurement operators for the full rovibronic density matrix in the symmetric top basis. A key revelation of our study is the direct link between Lagrange multipliers in the MaxEnt formalism and the unique set of MADMs. Additionally, we visualize the electron density within the molecular frame, demonstrating charge migration across the molecule. Furthermore, we achieve a groundbreaking milestone by constructing, for the first time, the entanglement entropy of the electronic subsystem─a metric that was previously inaccessible. The entropy vividly reveals and quantifies the effects of coupling between the excited electron and nuclear degrees of freedom. Consequently, our findings open new avenues for research in ultrafast molecular spectroscopy within the broader domain of quantum information science, offering profound implications for the study of molecular systems under excitation using quantum tomographic schemes.
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Affiliation(s)
- Varun Makhija
- Department of Chemistry and Physics, University of Mary Washington, Fredericksburg, Virginia 22401, United States
| | - Rishabh Gupta
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States
| | - Simon Neville
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Michael Schuurman
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Chemistry, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Joseph Francisco
- Department of Earth and Environmental Science and Department of Chemistry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, United States
| | - Sabre Kais
- Department of Electrical and Computer Engineering, North Carolina State University, Raleigh, North Carolina 27606, United States
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3
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Morrigan L, Neville SP, Gregory M, Boguslavskiy AE, Forbes R, Wilkinson I, Lausten R, Stolow A, Schuurman MS, Hockett P, Makhija V. Ultrafast Molecular Frame Quantum Tomography. PHYSICAL REVIEW LETTERS 2023; 131:193001. [PMID: 38000424 DOI: 10.1103/physrevlett.131.193001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/15/2023] [Revised: 09/05/2023] [Accepted: 10/03/2023] [Indexed: 11/26/2023]
Abstract
We develop and experimentally demonstrate a methodology for a full molecular frame quantum tomography (MFQT) of dynamical polyatomic systems. We exemplify this approach through the complete characterization of an electronically nonadiabatic wave packet in ammonia (NH_{3}). The method exploits both energy and time-domain spectroscopic data, and yields the lab frame density matrix (LFDM) for the system, the elements of which are populations and coherences. The LFDM fully characterizes electronic and nuclear dynamics in the molecular frame, yielding the time- and orientation-angle dependent expectation values of any relevant operator. For example, the time-dependent molecular frame electronic probability density may be constructed, yielding information on electronic dynamics in the molecular frame. In NH_{3}, we observe that electronic coherences are induced by nuclear dynamics which nonadiabatically drive electronic motions (charge migration) in the molecular frame. Here, the nuclear dynamics are rotational and it is nonadiabatic Coriolis coupling which drives the coherences. Interestingly, the nuclear-driven electronic coherence is preserved over longer timescales. In general, MFQT can help quantify entanglement between electronic and nuclear degrees of freedom, and provide new routes to the study of ultrafast molecular dynamics, charge migration, quantum information processing, and optimal control schemes.
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Affiliation(s)
- Luna Morrigan
- Department of Chemistry and Physics, University of Mary Washington, Fredericksburg, Virginia 22401, USA
| | - Simon P Neville
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Margaret Gregory
- Department of Chemistry and Physics, University of Mary Washington, Fredericksburg, Virginia 22401, USA
| | - Andrey E Boguslavskiy
- Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Ruaridh Forbes
- Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Iain Wilkinson
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Institute for Electronic Structure Dynamics, Helmholtz-Zentrum für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin, Germany
| | - Rune Lausten
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Albert Stolow
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
- NRC-uOttawa Joint Centre for Extreme and Quantum Photonics (JCEP), Ottawa, Ontario K1A 0R6, Canada
| | - Michael S Schuurman
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
| | - Paul Hockett
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Varun Makhija
- Department of Chemistry and Physics, University of Mary Washington, Fredericksburg, Virginia 22401, USA
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4
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Crane S, Garrow M, Lane PD, Robertson K, Waugh A, Woolley JM, Stavros VG, Paterson MJ, Greaves SJ, Townsend D. The Value of Different Experimental Observables: A Transient Absorption Study of the Ultraviolet Excitation Dynamics Operating in Nitrobenzene. J Phys Chem A 2023; 127:6425-6436. [PMID: 37494478 PMCID: PMC10424241 DOI: 10.1021/acs.jpca.3c02654] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2023] [Revised: 06/16/2023] [Indexed: 07/28/2023]
Abstract
Excess energy redistribution dynamics operating in nitrobenzene under hexane and isopropanol solvation were investigated using ultrafast transient absorption spectroscopy (TAS) with a 267 nm pump and a 340-750 nm white light continuum probe. The use of a nonpolar hexane solvent provides a proxy to the gas-phase environment, and the findings are directly compared with a recent time-resolved photoelectron imaging (TRPEI) study on nitrobenzene using the same excitation wavelength [L. Saalbach et al., J. Phys. Chem. A 2021, 125, 7174-7184]. Of note is the observation of a 1/e lifetime of 3.5-6.7 ps in the TAS data that was absent in the TRPEI measurements. This is interpreted as a dynamical signature of the T2 state in nitrobenzene─analogous to observations in the related nitronaphthalene system, and additionally supported by previous quantum chemistry calculations. The discrepancy between the TAS and TRPEI measurements is discussed, with the overall findings providing an example of how different spectroscopic techniques can exhibit varying sensitivity to specific steps along the overall reaction coordinate connecting reactants to photoproducts.
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Affiliation(s)
- Stuart
W. Crane
- Institute
of Photonics & Quantum Sciences, Heriot-Watt
University, Edinburgh EH14 4AS, U.K.
| | - Malcolm Garrow
- Institute
of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
| | - Paul D. Lane
- Institute
of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
| | - Kate Robertson
- Institute
of Photonics & Quantum Sciences, Heriot-Watt
University, Edinburgh EH14 4AS, U.K.
| | - Alex Waugh
- Institute
of Photonics & Quantum Sciences, Heriot-Watt
University, Edinburgh EH14 4AS, U.K.
| | - Jack M. Woolley
- Department
of Physics, University of Warwick, Coventry CV4 7AL, U.K.
| | - Vasilios G. Stavros
- School
of Chemistry, University of Birmingham, Edgbaston, Birmingham B15 2TT, U.K.
| | - Martin J. Paterson
- Institute
of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
| | - Stuart J. Greaves
- Institute
of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
| | - Dave Townsend
- Institute
of Photonics & Quantum Sciences, Heriot-Watt
University, Edinburgh EH14 4AS, U.K.
- Institute
of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
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5
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Hollerith S, Zeiher J. Rydberg Macrodimers: Diatomic Molecules on the Micrometer Scale. J Phys Chem A 2023; 127:3925-3939. [PMID: 36977279 PMCID: PMC10184126 DOI: 10.1021/acs.jpca.2c08454] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2022] [Revised: 03/17/2023] [Indexed: 03/30/2023]
Abstract
Controlling molecular binding at the level of single atoms is one of the holy grails of quantum chemistry. Rydberg macrodimers─bound states between highly excited Rydberg atoms─provide a novel perspective in this direction. Resulting from binding potentials formed by the strong, long-range interactions of Rydberg states, Rydberg macrodimers feature bond lengths in the micrometer regime, exceeding those of conventional molecules by orders of magnitude. Using single-atom control in quantum gas microscopes, the unique properties of these exotic states can be studied with unprecedented control, including the response to magnetic fields or the polarization of light in their photoassociation. The high accuracy achieved in spectroscopic studies of macrodimers makes them an ideal testbed to benchmark Rydberg interactions, with direct relevance to quantum computing and information protocols where these are employed. This review provides a historic overview and summarizes the recent findings in the field of Rydberg macrodimers. Furthermore, it presents new data on interactions between macrodimers, leading to a phenomenon analogous to Rydberg blockade at the level of molecules, opening the path toward studying many-body systems of ultralong-range Rydberg molecules.
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Affiliation(s)
- Simon Hollerith
- Max-Planck-Institut
für Quantenoptik, 85748 Garching, Germany
| | - Johannes Zeiher
- Max-Planck-Institut
für Quantenoptik, 85748 Garching, Germany
- Munich
Center for Quantum Science and Technology (MCQST), 80799 Munich, Germany
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6
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Takatsuka K. Quantum Chaos in the Dynamics of Molecules. ENTROPY (BASEL, SWITZERLAND) 2022; 25:63. [PMID: 36673204 PMCID: PMC9857761 DOI: 10.3390/e25010063] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/22/2022] [Accepted: 12/22/2022] [Indexed: 06/17/2023]
Abstract
Quantum chaos is reviewed from the viewpoint of "what is molecule?", particularly placing emphasis on their dynamics. Molecules are composed of heavy nuclei and light electrons, and thereby the very basic molecular theory due to Born and Oppenheimer gives a view that quantum electronic states provide potential functions working on nuclei, which in turn are often treated classically or semiclassically. Therefore, the classic study of chaos in molecular science began with those nuclear dynamics particularly about the vibrational energy randomization within a molecule. Statistical laws in probabilities and rates of chemical reactions even for small molecules of several atoms are among the chemical phenomena requiring the notion of chaos. Particularly the dynamics behind unimolecular decomposition are referred to as Intra-molecular Vibrational energy Redistribution (IVR). Semiclassical mechanics is also one of the main research fields of quantum chaos. We herein demonstrate chaos that appears only in semiclassical and full quantum dynamics. A fundamental phenomenon possibly giving birth to quantum chaos is "bifurcation and merging" of quantum wavepackets, rather than "stretching and folding" of the baker's transformation and the horseshoe map as a geometrical foundation of classical chaos. Such wavepacket bifurcation and merging are indeed experimentally measurable as we showed before in the series of studies on real-time probing of nonadiabatic chemical reactions. After tracking these aspects of molecular chaos, we will explore quantum chaos found in nonadiabatic electron wavepacket dynamics, which emerges in the realm far beyond the Born-Oppenheimer paradigm. In this class of chaos, we propose a notion of Intra-molecular Nonadiabatic Electronic Energy Redistribution (INEER), which is a consequence of the chaotic fluxes of electrons and energy within a molecule.
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Affiliation(s)
- Kazuo Takatsuka
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan
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7
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Kotsina N, Jackson SL, Malcomson T, Paterson MJ, Townsend D. Photochemical carbon-sulfur bond cleavage in thioethers mediated via excited state Rydberg-to-valence evolution. Phys Chem Chem Phys 2022; 24:29423-29436. [PMID: 36453640 DOI: 10.1039/d2cp04789f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/03/2022]
Abstract
Time-resolved photoelectron imaging and supporting ab initio quantum chemistry calculations were used to investigate non-adiabatic excess energy redistribution dynamics operating in the saturated thioethers diethylsulfide, tetrahydrothiophene and thietane. In all cases, 200 nm excitation leads to molecular fragmentation on an ultrafast (<100 fs) timescale, driven by the evolution of Rydberg-to-valence orbital character along the S-C stretching coordinate. The C-S-C bending angle was also found to be a key coordinate driving initial internal conversion through the excited state Rydberg manifold, although only small angular displacements away from the ground state equilibrium geometry are required. Conformational constraints imposed by the cyclic ring structures of tetrahydrothiophene and thietane do not therefore influence dynamical timescales to any significant extent. Through use of a high-intensity 267 nm probe, we were also able to detect the presence of some transient (bi)radical species. These are extremely short lived, but they appear to confirm the presence of two competing excited state fragmentation channels - one proceeding directly from the initially prepared 4p manifold, and one involving non-adiabatic population of the 4s state. This is in addition to a decay pathway leading back to the S0 electronic ground state, which shows an enhanced propensity in the 5-membered ring system tetrahydrothiophene over the other two species investigated.
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Affiliation(s)
- Nikoleta Kotsina
- Institute of Photonics & Quantum Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Sebastian L Jackson
- Institute of Photonics & Quantum Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK
| | - Thomas Malcomson
- Department of Chemistry, University of Manchester, Oxford Road, Manchester, M13 9PL, UK
| | - Martin J Paterson
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
| | - Dave Townsend
- Institute of Photonics & Quantum Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.,Institute of Chemical Sciences, Heriot-Watt University, Edinburgh, EH14 4AS, UK.
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8
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Gregory M, Neville S, Schuurman M, Makhija V. A laboratory frame density matrix for ultrafast quantum molecular dynamics. J Chem Phys 2022; 157:164301. [DOI: 10.1063/5.0109607] [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
In most cases, the ultrafast dynamics of resonantly excited molecules are considered and almost always computed in the molecular frame, while experiments are carried out in the laboratory frame. Here, we provide a formalism in terms of a lab frame density matrix, which connects quantum dynamics in the molecular frame to those in the laboratory frame, providing a transparent link between computation and measurement. The formalism reveals that in any such experiment, the molecular frame dynamics vary for molecules in different orientations and that certain coherences, which are potentially experimentally accessible, are rejected by the orientation-averaged reduced vibronic density matrix. Instead, molecular angular distribution moments are introduced as a more accurate representation of experimentally accessible information. Furthermore, the formalism provides a clear definition of a molecular frame quantum tomography and specifies the requirements to perform such a measurement enabling the experimental imaging of molecular frame vibronic dynamics. Successful completion of such a measurement fully characterizes the molecular frame quantum dynamics for a molecule at any orientation in the laboratory frame.
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Affiliation(s)
- Margaret Gregory
- Department of Chemistry and Physics, University of Mary Washington, 1301 College Avenue, Fredericksburg, Virginia 22401, USA
| | - Simon Neville
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Michael Schuurman
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 150 Louis Pasteur, Ottawa, Ontario K1N 6N5, Canada
| | - Varun Makhija
- Department of Chemistry and Physics, University of Mary Washington, 1301 College Avenue, Fredericksburg, Virginia 22401, USA
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9
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Gibbard JA, Verlet JRR. Kasha's Rule and Koopmans' Correlations for Electron Tunnelling through Repulsive Coulomb Barriers in a Polyanion. J Phys Chem Lett 2022; 13:7797-7801. [PMID: 35973214 PMCID: PMC9421885 DOI: 10.1021/acs.jpclett.2c02145] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2022] [Accepted: 08/11/2022] [Indexed: 05/17/2023]
Abstract
The long-range electronic structure of polyanions is defined by the repulsive Coulomb barrier (RCB). Excited states can decay by resonant electron tunnelling through RCBs, but such decay has not been observed for electronically excited states other than the first excited state, suggesting a Kasha-type rule for resonant electron tunnelling. Using action spectroscopy, photoelectron imaging, and computational chemistry, we show that the fluorescein dianion, Fl2-, partially decays through electron tunnelling from the S2 excited state, thus demonstrating anti-Kasha behavior, and that resonant electron tunnelling adheres to Koopmans' correlations, thus disentangling different channels.
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Affiliation(s)
- Jemma A. Gibbard
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Jan R. R. Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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10
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Wang Y, Wei J, Cao L, Zhang B, Zhang S. The ultrafast nonradiative processes and photodissociation dynamics investigation of S1 state in propanal. J Chem Phys 2022; 156:074306. [DOI: 10.1063/5.0077490] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Yanmei Wang
- Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology CAS, China
| | - Jie Wei
- Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences, China
| | - Ling Cao
- Innovation Academy for Precision Measurement Science and Technology CAS, China
| | - Bing Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences, China
| | - Song Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics Chinese Academy of Sciences, China
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11
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Seidu I, Neville SP, MacDonell RJ, Schuurman MS. Resolving competing conical intersection pathways: time-resolved X-ray absorption spectroscopy of trans-1,3-butadiene. Phys Chem Chem Phys 2021; 24:1345-1354. [PMID: 34935809 DOI: 10.1039/d1cp05085k] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Time-resolved X-ray absorption spectroscopy is emerging as a uniquely powerful tool to probe coupled electronic-nuclear dynamics in photo-excited molecules. Theoretical studies to date have established that time-resolved X-ray absorption spectroscopy is an atom-specific probe of excited-state wave packet passage through a seam of conical intersections (CIs). However, in many molecular systems, there are competing dynamical pathways involving CIs of different electronic and nuclear character. Discerning these pathways remains an important challenge. Here, we demonstrate that time-resolved X-ray absorption spectroscopy (TRXAS) has the potential to resolve competing channels in excited-state non-adiabatic dynamics. Using the example of 1,3-butadiene, we show how TRXAS discerns the different electronic structures associated with passage through multiple conical intersections. trans-1,3-Butadiene exhibits a branching between polarized and radicaloid pathways associated with ethylenic "twisted-pyramidalized" and excited-state cis-trans isomerization dynamics, respectively. The differing electronic structures along these pathways give rise to different XAS signals, indicating the possibility of resolving them. Furthermore, this indicates that XAS, and other core-level spectroscopic techniques, offer the appealing prospect of directly probing the effects of selective chemical substitution and its ability to affect chemical control over excited-state molecular dynamics.
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Affiliation(s)
- Issaka Seidu
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.
| | - Simon P Neville
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.
| | - Ryan J MacDonell
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada
| | - Michael S Schuurman
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada. .,Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, K1N 6N5, Canada
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12
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Skov AB, Folkmann LM, Boguslavskiy AE, Röder A, Lausten R, Stolow A, Johnson MS, Pittelkow M, Nielsen OJ, Sølling TI, Hansen T. The Sulfolene Protecting Group: Observation of a Direct Photoinitiated Cheletropic Ring Opening. CHEMPHOTOCHEM 2021. [DOI: 10.1002/cptc.202100048] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Anders B. Skov
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 København Ø Denmark
| | - Linnea M. Folkmann
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 København Ø Denmark
| | - Andrey E. Boguslavskiy
- Joint Centre for Extreme Photonics National Research Council and University of Ottawa Ottawa ON, K1A 0R6 Canada
- Department of Physics University of Ottawa 150 Louis-Pasteur Pvt Ottawa ON, K1N 6N5 Canada
- Department of Chemistry University of Ottawa 150 Louis-Pasteur Pvt Ottawa ON K1N 6N5 Canada
- National Research Council Canada 100 Sussex Drive Ottawa ON K1N 5A2 Canada
| | - Anja Röder
- Joint Centre for Extreme Photonics National Research Council and University of Ottawa Ottawa ON, K1A 0R6 Canada
- Department of Chemistry University of Ottawa 150 Louis-Pasteur Pvt Ottawa ON K1N 6N5 Canada
| | - Rune Lausten
- National Research Council Canada 100 Sussex Drive Ottawa ON K1N 5A2 Canada
| | - Albert Stolow
- Joint Centre for Extreme Photonics National Research Council and University of Ottawa Ottawa ON, K1A 0R6 Canada
- Department of Physics University of Ottawa 150 Louis-Pasteur Pvt Ottawa ON, K1N 6N5 Canada
- Department of Chemistry University of Ottawa 150 Louis-Pasteur Pvt Ottawa ON K1N 6N5 Canada
- National Research Council Canada 100 Sussex Drive Ottawa ON K1N 5A2 Canada
| | - Matthew S. Johnson
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 København Ø Denmark
| | - Michael Pittelkow
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 København Ø Denmark
| | - Ole John Nielsen
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 København Ø Denmark
| | - Theis I. Sølling
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 København Ø Denmark
- King Fahd University of Petroleum and Minerals Bldg. 15, Rm. 6124 Dhahran 31261, Kingdom of Saudi Arabia
| | - Thorsten Hansen
- Department of Chemistry University of Copenhagen Universitetsparken 5 2100 København Ø Denmark
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13
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Saalbach L, Kotsina N, Crane SW, Paterson MJ, Townsend D. Ultraviolet Excitation Dynamics of Nitrobenzenes. J Phys Chem A 2021; 125:7174-7184. [PMID: 34379417 DOI: 10.1021/acs.jpca.1c04893] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Time-resolved photoelectron imaging was used to investigate nonadiabatic processes operating in the excited electronic states of nitrobenzene and three methyl-substituted derivatives: 3,5-, 2,6-, and 2,4-dimethylnitrobenzene. The primary goal was evaluating the dynamical impact of the torsional angle between the NO2 group and the benzene ring plane-something previously implicated in mediating the propensity for branching into different photodissociation pathways (NO vs NO2 elimination). Targeted, photoinitiated release of NO radicals is of interest for clinical medicine applications, and there is a need to establish basic structure-dynamics-function principles in systematically varied model systems following photoexcitation. Within our 200 ps experimental detection window, we observed no significant differences in the excited-state lifetimes exhibited by all species under study using a 267 nm pump and ionization with an intense 400 nm probe. In agreement with previous theoretical predictions, this suggests that the initial energy redistribution dynamics within the singlet and triplet manifolds are driven by motions localized predominantly on the NO2 group. Our findings also imply that both NO and NO2 elimination occur from a vibrationally hot ground state on extended (nanosecond) timescales, and any variations in NO vs NO2 branching upon site-selective methylation are due to steric effects influencing isomerization prior to dissociation.
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Affiliation(s)
- Lisa Saalbach
- Institute of Photonics & Quantum Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Nikoleta Kotsina
- Institute of Photonics & Quantum Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Stuart W Crane
- Institute of Photonics & Quantum Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Martin J Paterson
- Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
| | - Dave Townsend
- Institute of Photonics & Quantum Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.,Institute of Chemical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K
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14
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Chakraborty P, Liu Y, McClung S, Weinacht T, Matsika S. Time Resolved Photoelectron Spectroscopy as a Test of Electronic Structure and Nonadiabatic Dynamics. J Phys Chem Lett 2021; 12:5099-5104. [PMID: 34028278 DOI: 10.1021/acs.jpclett.1c00926] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
We compare different levels of theory for simulating excited state molecular dynamics and use time-resolved photoelectron spectroscopy measurements to benchmark the theory. We perform trajectory surface hopping simulations for uracil excited to the first bright state (ππ*) using three different levels of theory (CASSCF, MRCIS, and XMS-CASPT2) in order to understand the role of dynamical correlation in determining the excited state dynamics, with a focus on the coupling between different electronic states and internal conversion back to the ground state. These dynamics calculations are used to simulate the time-resolved photoelectron spectra. The comparison of the calculated and measured spectra allows us to draw conclusions regarding the relative insights and quantitative accuracy of the calculations at the three different levels of theory, demonstrating that detailed quantitative comparisons of time-resolved photoelectron spectra can be used to benchmark methodology.
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Affiliation(s)
- Pratip Chakraborty
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
| | - Yusong Liu
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, United States
| | - Samuel McClung
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, United States
| | - Thomas Weinacht
- Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794, United States
| | - Spiridoula Matsika
- Department of Chemistry, Temple University, Philadelphia, Pennsylvania 19122, United States
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15
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Kotsina N, Townsend D. Improved insights in time-resolved photoelectron imaging. Phys Chem Chem Phys 2021; 23:10736-10755. [DOI: 10.1039/d1cp00933h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We review new light source developments and data analysis considerations relevant to the time-resolved photoelectron imaging technique. Case studies illustrate how these themes may enhance understanding in studies of excited state molecular dynamics.
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Affiliation(s)
- Nikoleta Kotsina
- Institute of Photonics & Quantum Sciences
- Heriot-Watt University
- Edinburgh
- UK
| | - Dave Townsend
- Institute of Photonics & Quantum Sciences
- Heriot-Watt University
- Edinburgh
- UK
- Institute of Chemical Sciences
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16
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Zhou W, Ge L, Cooper GA, Crane SW, Evans MH, Ashfold MNR, Vallance C. Coulomb explosion imaging for gas-phase molecular structure determination: An ab initio trajectory simulation study. J Chem Phys 2020; 153:184201. [PMID: 33187401 DOI: 10.1063/5.0024833] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Coulomb explosion velocity-map imaging is a new and potentially universal probe for gas-phase chemical dynamics studies, capable of yielding direct information on (time-evolving) molecular structure. The approach relies on a detailed understanding of the mapping between the initial atomic positions within the molecular structure of interest and the final velocities of the fragments formed via Coulomb explosion. Comprehensive on-the-fly ab initio trajectory studies of the Coulomb explosion dynamics are presented for two prototypical small molecules, formyl chloride and cis-1,2-dichloroethene, in order to explore conditions under which reliable structural information can be extracted from fragment velocity-map images. It is shown that for low parent ion charge states, the mapping from initial atomic positions to final fragment velocities is complex and very sensitive to the parent ion charge state as well as many other experimental and simulation parameters. For high-charge states, however, the mapping is much more straightforward and dominated by Coulombic interactions (moderated, if appropriate, by the requirements of overall spin conservation). This study proposes minimum requirements for the high-charge regime, highlights the need to work in this regime in order to obtain robust structural information from fragment velocity-map images, and suggests how quantitative structural information may be extracted from experimental data.
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Affiliation(s)
- Weiwei Zhou
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Rd., Oxford OX1 3TA, United Kingdom
| | - Lingfeng Ge
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Graham A Cooper
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Stuart W Crane
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Michael H Evans
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Michael N R Ashfold
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, United Kingdom
| | - Claire Vallance
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory, 12 Mansfield Rd., Oxford OX1 3TA, United Kingdom
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17
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Fenwick KL, England DG, Bustard PJ, Fraser JM, Sussman BJ. Carving out configurable ultrafast pulses from a continuous wave source via the optical Kerr effect. OPTICS EXPRESS 2020; 28:24845-24853. [PMID: 32907016 DOI: 10.1364/oe.399878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Accepted: 07/30/2020] [Indexed: 06/11/2023]
Abstract
Wavelength-tunable, time-locked pairs of ultrafast pulses are crucial in modern-day time-resolved measurements. We demonstrate a simple means of generating configurable optical pulse sequences: sub-picosecond pulses are carved out from a continuous wave laser via pump-induced optical Kerr switching in 10 cm of a commercial single-mode fiber. By introducing dispersion to the pump, the near transform-limited switched pulse duration is tuned between 305-570 fs. Two- and four-pulse signal trains are also generated by adding birefringent α-BBO plates in the pump beam. These results highlight an ultrafast light source with intrinsic timing stability and pulse-to-pulse phase coherence, where pulse generation could be adapted to wavelengths ranging from ultraviolet to infrared.
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18
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Anstöter CS, Curchod BFE, Verlet JRR. Geometric and electronic structure probed along the isomerisation coordinate of a photoactive yellow protein chromophore. Nat Commun 2020; 11:2827. [PMID: 32499507 PMCID: PMC7272410 DOI: 10.1038/s41467-020-16667-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 05/15/2020] [Indexed: 01/29/2023] Open
Abstract
Understanding the connection between the motion of the nuclei in a molecule and the rearrangement of its electrons lies at the heart of chemistry. While many experimental methods have been developed to probe either the electronic or the nuclear structure on the timescale of atomic motion, very few have been able to capture both these changes in concert. Here, we use time-resolved photoelectron imaging to probe the isomerisation coordinate on the excited state of an isolated model chromophore anion of the photoactive yellow protein. By probing both the electronic structure changes as well as nuclear dynamics, we are able to uniquely measure isomerisation about a specific bond. Our results demonstrate that the photoelectron signal dispersed in time, energy and angle combined with calculations can track the evolution of both electronic and geometric structure along the adiabatic state, which in turn defines that chemical transformation. Resolving concerted nuclear and electronic motion in real-time is a primary goal in chemistry. The authors monitor nuclear and valence electronic dynamics in the excited state single-bond isomerisation of a chromophore of photoactive yellow protein, using time-resolved photoelectron imaging and electronic structure calculations.
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Affiliation(s)
- Cate S Anstöter
- Department of Chemistry, Durham University, Durham, DH1 3LE, UK
| | | | - Jan R R Verlet
- Department of Chemistry, Durham University, Durham, DH1 3LE, UK.
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19
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Verlet JRR, Anstöter CS, Bull JN, Rogers JP. Role of Nonvalence States in the Ultrafast Dynamics of Isolated Anions. J Phys Chem A 2020; 124:3507-3519. [PMID: 32233436 PMCID: PMC7212518 DOI: 10.1021/acs.jpca.0c01260] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
Nonvalence states
of neutral molecules (Rydberg states) play important
roles in nonadiabatic dynamics of excited states. In anions, such
nonadiabatic transitions between nonvalence and valence states have
been much less explored even though they are believed to play important
roles in electron capture and excited state dynamics of anions. The
aim of this Feature Article is to provide an overview of recent experimental
observations, based on time-resolved photoelectron imaging, of valence
to nonvalence and nonvalence to valence transitions in anions and
to demonstrate that such dynamics may be commonplace in the excited
state dynamics of molecular anions and cluster anions.
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Affiliation(s)
- Jan R R Verlet
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - Cate S Anstöter
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
| | - James N Bull
- School of Chemistry, Norwich Research Park, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Joshua P Rogers
- Department of Chemistry, Durham University, Durham DH1 3LE, United Kingdom
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20
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Patel K, Bittner ER. Mixed Quantum Classical Simulations of Charge-Transfer Dynamics in a Model Light-Harvesting Complex. II. Transient Vibrational Analysis. J Phys Chem B 2020; 124:2158-2167. [PMID: 32118439 DOI: 10.1021/acs.jpcb.0c00203] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
We perform dynamics simulations of donor-bridge-acceptor triads following photoexcitation and correlate nuclear motions with the charge-transfer event using the short-time Fourier transform technique. Broadly, the porphyrin bridges undergo higher energy vibrations, whereas the fullerene acceptors undergo low energy modes. Aryl side groups exhibit torsional motions relative to the porphyrin. Aryl linkers between the bridge and acceptor are restricted from such motions and therefore express ring distortion modes. Finally, we find an amide linker mode that is directionally sensitive to electron motion. This work supports the notion of vibrationally coupled ultrafast charge transfer found in both experimental and theoretical studies and lays a foundational method for identifying key vibrational modes for parametrizing future theoretical models.
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Affiliation(s)
- Kush Patel
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States
| | - Eric R Bittner
- Department of Chemistry, University of Houston, Houston, Texas 77204, United States.,Department of Physics, Durham University, South Road, Durham DH1 3LE, United Kingdom
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21
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Heim P, Mai S, Thaler B, Cesnik S, Avagliano D, Bella-Velidou D, Ernst WE, González L, Koch M. Revealing Ultrafast Population Transfer between Nearly Degenerate Electronic States. J Phys Chem Lett 2020; 11:1443-1449. [PMID: 31918552 PMCID: PMC7052817 DOI: 10.1021/acs.jpclett.9b03462] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2019] [Accepted: 01/10/2020] [Indexed: 06/10/2023]
Abstract
The response of a molecule to photoexcitation is governed by the coupling of its electronic states. However, if the energetic spacing between the electronically excited states at the Franck-Condon window becomes sufficiently small, it is infeasible to selectively excite and monitor individual states with conventional time-resolved spectroscopy, preventing insight into the energy transfer and relaxation dynamics of the molecule. Here, we demonstrate how the combination of time-resolved spectroscopy and extensive surface hopping dynamics simulations with a global fit approach on individually excited ensembles overcomes this limitation and resolves the dynamics in the n3p Rydberg states in acetone. Photoelectron transients of the three closely spaced states n3px, n3py, and n3pz are used to validate the theoretical results, which in turn allow retrieving a comprehensive kinetic model describing the mutual interactions of these states for the first time.
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Affiliation(s)
- Pascal Heim
- Institute
of Experimental Physics, Graz University
of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Sebastian Mai
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, A-1090 Vienna, Austria
| | - Bernhard Thaler
- Institute
of Experimental Physics, Graz University
of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Stefan Cesnik
- Institute
of Experimental Physics, Graz University
of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Davide Avagliano
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, A-1090 Vienna, Austria
| | - Dimitra Bella-Velidou
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, A-1090 Vienna, Austria
| | - Wolfgang E. Ernst
- Institute
of Experimental Physics, Graz University
of Technology, Petersgasse 16, A-8010 Graz, Austria
| | - Leticia González
- Institute
of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, A-1090 Vienna, Austria
| | - Markus Koch
- Institute
of Experimental Physics, Graz University
of Technology, Petersgasse 16, A-8010 Graz, Austria
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22
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Wolf TJA, Parrish RM, Myhre RH, Martínez TJ, Koch H, Gühr M. Observation of Ultrafast Intersystem Crossing in Thymine by Extreme Ultraviolet Time-Resolved Photoelectron Spectroscopy. J Phys Chem A 2019; 123:6897-6903. [PMID: 31319031 DOI: 10.1021/acs.jpca.9b05573] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We studied the photoinduced ultrafast relaxation dynamics of the nucleobase thymine using gas-phase time-resolved photoelectron spectroscopy. By employing extreme ultraviolet pulses from high harmonic generation for photoionization, we substantially extend our spectral observation window with respect to previous studies. This enables us to follow relaxation of the excited state population all the way to low-lying electronic states including the ground state. In thymine, we observe relaxation from the optically bright 1ππ* state of thymine to a dark 1nπ* state within 80 ± 30 fs. The 1nπ* state relaxes further within 3.5 ± 0.3 ps to a low-lying electronic state. By comparison with quantum chemical simulations, we can unambiguously assign its spectroscopic signature to the 3ππ* state. Hence, our study draws a comprehensive picture of the relaxation mechanism of thymine including ultrafast intersystem crossing to the triplet manifold.
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Affiliation(s)
- Thomas J A Wolf
- Stanford PULSE Institute , SLAC National Accelerator Laboratory , Menlo Park , California 94025 , United States
| | - Robert M Parrish
- Stanford PULSE Institute , SLAC National Accelerator Laboratory , Menlo Park , California 94025 , United States.,Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Rolf H Myhre
- Department of Chemistry , Norwegian University of Science and Technology , NO-7491 Trondheim , Norway
| | - Todd J Martínez
- Stanford PULSE Institute , SLAC National Accelerator Laboratory , Menlo Park , California 94025 , United States.,Department of Chemistry , Stanford University , Stanford , California 94305 , United States
| | - Henrik Koch
- Scuola Normale Superiore , Piazza dei Cavalieri, 7 , 56126 Pisa , PI , Italy
| | - Markus Gühr
- Stanford PULSE Institute , SLAC National Accelerator Laboratory , Menlo Park , California 94025 , United States.,Institut für Physik und Astronomie , Universität Potsdam , 14476 Potsdam , Germany
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23
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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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24
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Steglich M, Knopp G, Hemberger P. How the methyl group position influences the ultrafast deactivation in aromatic radicals. Phys Chem Chem Phys 2019; 21:581-588. [DOI: 10.1039/c8cp06087h] [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
Excited xylyl (methyl–benzyl) radical isomers have been studied by femtosecond time-resolved photoelectron spectroscopy and mass spectrometry.
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Affiliation(s)
| | - Gregor Knopp
- Paul Scherrer Institute
- CH-5232 Villigen-PSI
- Switzerland
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25
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Ashfold MNR, Ingle RA, Karsili TNV, Zhang J. Photoinduced C–H bond fission in prototypical organic molecules and radicals. Phys Chem Chem Phys 2019; 21:13880-13901. [DOI: 10.1039/c8cp07454b] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
We survey and assess current knowledge regarding the primary photochemistry of hydrocarbon molecules and radicals.
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Affiliation(s)
| | | | | | - Jingsong Zhang
- Department of Chemistry
- University of California at Riverside
- Riverside
- USA
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26
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Issler K, Röder A, Hirsch F, Poisson L, Fischer I, Mitrić R, Petersen J. Excited state dynamics and time-resolved photoelectron spectroscopy of para-xylylene. Faraday Discuss 2018; 212:83-100. [PMID: 30238117 DOI: 10.1039/c8fd00083b] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We investigated the excited-state dynamics of para-xylylene using a combination of field-induced surface hopping (FISH) simulations and time-resolved ionisation experiments. Our simulations predict an ultrafast decay of the initially excited bright state (S2/S3) to the S1 state on a sub-100 fs time scale, followed by return to the ground state within ∼1 ps. This is accompanied by a transient change of the biradical character of the molecule, as monitored by calculating natural orbital occupation numbers. Specifically, the initially low biradicality is increased by electronic excitation as well as by vibrational activation. Experimentally, para-xylylene was generated by pyrolysis from [2,2]paracyclophane and excited with 266 nm radiation into the S2/S3 bright state. The subsequent dynamics were followed using ionisation as the probe step, with both mass spectra and photoelectron spectra recorded as a function of pump-probe delay. The observed decay of photoelectron and photoion intensities closely matches the theoretical predictions and is consistent with the sequential mechanism found in the simulations. This mechanism exhibits characteristic signatures in both time-resolved mass and photoelectron spectra, in particular in the appearance of fragment ions that are exclusively generated from the S1 state. This allows for a separation of the S2 and S1 dynamics in the photoelectron and mass spectra. An excellent agreement between the observed and the simulated ion signal is observed.
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Affiliation(s)
- Kevin Issler
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
| | - Anja Röder
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany. and LIDYL, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France.
| | - Florian Hirsch
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
| | - Lionel Poisson
- LIDYL, CEA, CNRS, Université Paris-Saclay, CEA Saclay, 91191 Gif-sur-Yvette, France.
| | - Ingo Fischer
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
| | - Roland Mitrić
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
| | - Jens Petersen
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
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27
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Dsouza R, Cheng X, Li Z, Miller RJD, Kochman MA. Oscillatory Photoelectron Signal of N-Methylmorpholine as a Test Case for the Algebraic-Diagrammatic Construction Method of Second Order. J Phys Chem A 2018; 122:9688-9700. [DOI: 10.1021/acs.jpca.8b10241] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Raison Dsouza
- Max Planck Institute for the Structure and Dynamics of Matter, Bldg. 99 (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Xinxin Cheng
- Max Planck Institute for the Structure and Dynamics of Matter, Bldg. 99 (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany
- Hamburg Centre for Ultrafast Imaging (CUI), Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Zheng Li
- Max Planck Institute for the Structure and Dynamics of Matter, Bldg. 99 (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany
| | - R. J. Dwayne Miller
- Max Planck Institute for the Structure and Dynamics of Matter, Bldg. 99 (CFEL), Luruper Chaussee 149, 22761 Hamburg, Germany
- Hamburg Centre for Ultrafast Imaging (CUI), Universität Hamburg, Luruper Chaussee 149, 22761 Hamburg, Germany
- Department of Chemistry and Physics, University of Toronto, 80 St. George Street, Toronto, Ontario M5S 3H6, Canada
| | - Michał Andrzej Kochman
- Department of Physics, Chemistry and Biology (IFM), Linköping University, 581 83 Linköping, Sweden
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28
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Mignolet B, Kanno M, Shimakura N, Koseki S, Remacle F, Kono H, Fujimura Y. Ultrafast nonradiative transition pathways in photo-excited pyrazine: Ab initio analysis of time-resolved vacuum ultraviolet photoelectron spectrum. Chem Phys 2018. [DOI: 10.1016/j.chemphys.2018.07.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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29
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Thaler B, Ranftl S, Heim P, Cesnik S, Treiber L, Meyer R, Hauser AW, Ernst WE, Koch M. Femtosecond photoexcitation dynamics inside a quantum solvent. Nat Commun 2018; 9:4006. [PMID: 30275442 PMCID: PMC6167364 DOI: 10.1038/s41467-018-06413-9] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Accepted: 08/29/2018] [Indexed: 11/13/2022] Open
Abstract
The observation of chemical reactions on the time scale of the motion of electrons and nuclei has been made possible by lasers with ever shortened pulse lengths. Superfluid helium represents a special solvent that permits the synthesis of novel classes of molecules that have eluded dynamical studies so far. However, photoexcitation inside this quantum solvent triggers a pronounced response of the solvation shell, which is not well understood. Here, we present a mechanistic description of the solvent response to photoexcitation of indium (In) dopant atoms inside helium nanodroplets (HeN), obtained from femtosecond pump–probe spectroscopy and time-dependent density functional theory simulations. For the In–HeN system, part of the excited state electronic energy leads to expansion of the solvation shell within 600 fs, initiating a collective shell oscillation with a period of about 30 ps. These coupled electronic and nuclear dynamics will be superimposed on intrinsic photoinduced processes of molecular systems inside helium droplets. Femtosecond laser spectroscopy has contributed to our understanding of structure and function of matter. Here, the authors explore the applicability of superfluid helium nanodroplets as a sample preparation method that allows investigation of previously inaccessible classes of tailor-made or fragile molecular systems.
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Affiliation(s)
- Bernhard Thaler
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Sascha Ranftl
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Pascal Heim
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Stefan Cesnik
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Leonhard Treiber
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Ralf Meyer
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Andreas W Hauser
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Wolfgang E Ernst
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria
| | - Markus Koch
- Institute of Experimental Physics, Graz University of Technology, Petersgasse 16, 8010, Graz, Austria.
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30
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Affiliation(s)
- Helen H. Fielding
- Department of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK
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31
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Boguslavskiy AE, Schalk O, Gador N, Glover WJ, Mori T, Schultz T, Schuurman MS, Martínez TJ, Stolow A. Excited state non-adiabatic dynamics of the smallest polyene, trans 1,3-butadiene. I. Time-resolved photoelectron-photoion coincidence spectroscopy. J Chem Phys 2018; 148:164302. [DOI: 10.1063/1.5016452] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Affiliation(s)
- Andrey E. Boguslavskiy
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Chemistry, University of Ottawa, Ottawa, Ontario K1A 0R6, Canada
| | - Oliver Schalk
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Niklas Gador
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - William J. Glover
- Department of Chemistry and PULSE Institute, Stanford University, Stanford, California 94305, USA
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - Toshifumi Mori
- Department of Chemistry and PULSE Institute, Stanford University, Stanford, California 94305, USA
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - Thomas Schultz
- Ulsan National Institute of Science and Technology, Ulju-gun, Ulsan 44919, South Korea
| | - Michael S. Schuurman
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Chemistry, University of Ottawa, Ottawa, Ontario K1A 0R6, Canada
| | - Todd J. Martínez
- Department of Chemistry and PULSE Institute, Stanford University, Stanford, California 94305, USA
- SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, California 94025, USA
| | - Albert Stolow
- National Research Council Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Chemistry, University of Ottawa, Ottawa, Ontario K1A 0R6, Canada
- Department of Physics, University of Ottawa, Ottawa, Ontario K1N 6N5, Canada
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32
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Affiliation(s)
- Michael S. Schuurman
- National Research Council of Canada, Ottawa, Ontario K1A 06A, Canada
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1A 0R6, Canada
| | - Albert Stolow
- National Research Council of Canada, Ottawa, Ontario K1A 06A, Canada
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, Ottawa, Ontario K1A 0R6, Canada
- Department of Physics, University of Ottawa, Ottawa, Ontario K1A 0R6, Canada
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Ultrafast 25-fs relaxation in highly excited states of methyl azide mediated by strong nonadiabatic coupling. Proc Natl Acad Sci U S A 2017; 114:E11072-E11081. [PMID: 29109279 DOI: 10.1073/pnas.1712566114] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Highly excited electronic states are challenging to explore experimentally and theoretically-due to the large density of states and the fact that small structural changes lead to large changes in electronic character with associated strong nonadiabatic dynamics. They can play a key role in astrophysical and ionospheric chemistry, as well as the detonation chemistry of high-energy density materials. Here, we implement ultrafast vacuum-UV (VUV)-driven electron-ion coincidence imaging spectroscopy to directly probe the reaction pathways of highly excited states of energetic molecules-in this case, methyl azide. Our data, combined with advanced theoretical simulations, show that photoexcitation of methyl azide by a 10-fs UV pulse at 8 eV drives fast structural changes and strong nonadiabatic coupling that leads to relaxation to other excited states on a surprisingly fast timescale of 25 fs. This ultrafast relaxation differs from dynamics occurring on lower excited states, where the timescale required for the wavepacket to reach a region of strong nonadiabatic coupling is typically much longer. Moreover, our theoretical calculations show that ultrafast relaxation of the wavepacket to a lower excited state occurs along one of the conical intersection seams before reaching the minimum energy conical intersection. These findings are important for understanding the unique strongly coupled non-Born-Oppenheimer molecular dynamics of VUV-excited energetic molecules. Although such observations have been predicted for many years, this study represents one of the few where such strongly coupled non-Born-Oppenheimer molecular dynamics of VUV-excited energetic molecules have been conclusively observed directly, making it possible to identify the ultrafast reaction pathways.
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Zhou M, Zeng C, Sfeir MY, Cotlet M, Iida K, Nobusada K, Jin R. Evolution of Excited-State Dynamics in Periodic Au 28, Au 36, Au 44, and Au 52 Nanoclusters. J Phys Chem Lett 2017; 8:4023-4030. [PMID: 28796513 DOI: 10.1021/acs.jpclett.7b01597] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Understanding the correlation between the atomic structure and optical properties of gold nanoclusters is essential for exploration of their functionalities and applications involving light harvesting and electron transfer. We report the femto-nanosecond excited state dynamics of a periodic series of face-centered cubic (FCC) gold nanoclusters (including Au28, Au36, Au44, and Au52), which exhibit a set of unique features compared with other similar sized clusters. Molecular-like ultrafast Sn → S1 internal conversions (i.e., radiationless electronic transitions) are observed in the relaxation dynamics of FCC periodic series. Excited-state dynamics with near-HOMO-LUMO gap excitation lacks ultrafast decay component, and only the structural relaxation dominates in the dynamical process, which proves the absence of core-shell relaxation. Interestingly, both the relaxation of the hot carriers and the band-edge carrier recombination become slower as the size increases. The evolution in excited-state properties of this FCC series offers new insight into the structure-dependent properties of metal nanoclusters, which will benefit their optical energy harvesting and photocatalytic applications.
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Affiliation(s)
- Meng Zhou
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Chenjie Zeng
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
| | - Matthew Y Sfeir
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973, United States
| | - Mircea Cotlet
- Center for Functional Nanomaterials, Brookhaven National Laboratory , Upton, New York 11973, United States
| | - Kenji Iida
- Department of Theoretical and Computational Molecular Science, Institute for Molecular Science , Myodaiji, Okazaki, 444-8585, Japan
- Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University Katsura , Kyoto 615-8520, Japan
| | - Katsuyuki Nobusada
- Department of Theoretical and Computational Molecular Science, Institute for Molecular Science , Myodaiji, Okazaki, 444-8585, Japan
- Elements Strategy Initiative for Catalysts and Batteries (ESICB), Kyoto University Katsura , Kyoto 615-8520, Japan
| | - Rongchao Jin
- Department of Chemistry, Carnegie Mellon University , Pittsburgh, Pennsylvania 15213, United States
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36
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Monitoring non-adiabatic dynamics in CS2 with time- and energy-resolved photoelectron spectra of wavepackets. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.02.014] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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37
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Observing Femtosecond Fragmentation Using Ultrafast X-ray-Induced Auger Spectra. APPLIED SCIENCES-BASEL 2017. [DOI: 10.3390/app7070681] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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38
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Wolf TJA, Myhre RH, Cryan JP, Coriani S, Squibb RJ, Battistoni A, Berrah N, Bostedt C, Bucksbaum P, Coslovich G, Feifel R, Gaffney KJ, Grilj J, Martinez TJ, Miyabe S, Moeller SP, Mucke M, Natan A, Obaid R, Osipov T, Plekan O, Wang S, Koch H, Gühr M. Probing ultrafast ππ*/nπ* internal conversion in organic chromophores via K-edge resonant absorption. Nat Commun 2017; 8:29. [PMID: 28642477 PMCID: PMC5481431 DOI: 10.1038/s41467-017-00069-7] [Citation(s) in RCA: 113] [Impact Index Per Article: 16.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2017] [Accepted: 04/28/2017] [Indexed: 11/09/2022] Open
Abstract
Many photoinduced processes including photosynthesis and human vision happen in organic molecules and involve coupled femtosecond dynamics of nuclei and electrons. Organic molecules with heteroatoms often possess an important excited-state relaxation channel from an optically allowed ππ* to a dark nπ* state. The ππ*/nπ* internal conversion is difficult to investigate, as most spectroscopic methods are not exclusively sensitive to changes in the excited-state electronic structure. Here, we report achieving the required sensitivity by exploiting the element and site specificity of near-edge soft X-ray absorption spectroscopy. As a hole forms in the n orbital during ππ*/nπ* internal conversion, the absorption spectrum at the heteroatom K-edge exhibits an additional resonance. We demonstrate the concept using the nucleobase thymine at the oxygen K-edge, and unambiguously show that ππ*/nπ* internal conversion takes place within (60 ± 30) fs. High-level-coupled cluster calculations confirm the method's impressive electronic structure sensitivity for excited-state investigations.Many photo-induced processes such as photosynthesis occur in organic molecules, but their femtosecond excited-state dynamics are difficult to track. Here, the authors exploit the element and site selectivity of soft X-ray absorption to sensitively follow the ultrafast ππ*/nπ* electronic relaxation of hetero-organic molecules.
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Affiliation(s)
- T J A Wolf
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - R H Myhre
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
- Department of Chemistry, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway
| | - J P Cryan
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - S Coriani
- Dipartimento di Scienze Chimiche e Farmaceutiche, Università degli Studi di Trieste, Piazzale Europa 1, Trieste, IT-34127, Italy
- Department of Chemistry, Technical University of Denmark, 2800, Kongens Lyngby, Denmark
| | - R J Squibb
- Department of Physics, University of Gothenburg, SE-412 96, Gothenburg, Sweden
| | - A Battistoni
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - N Berrah
- Department of Physics, University of Connecticut, 2152 Hillside Road, Storrs, CT, 06269, USA
| | - C Bostedt
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
- Argonne National Laboratory, 9700 Cass Avenue, Lemont, IL, 60439, USA
- Department of Physics and Astronomy, Northwestern University, 2145 Sheridan Road, Evanston, IL, 60208, USA
| | - P Bucksbaum
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
- Department of Physics, Stanford University, 382 Via Pueblo Mall, Stanford, CA, 94305, USA
| | - G Coslovich
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - R Feifel
- Department of Physics, University of Gothenburg, SE-412 96, Gothenburg, Sweden
| | - K J Gaffney
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
- Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - J Grilj
- Laboratory of Ultrafast Spectroscopy, Ecole Polytechnique Federal de Lausanne, Lausanne, CH-1015, Switzerland
| | - T J Martinez
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305, USA
| | - S Miyabe
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
- Department of Chemistry, Stanford University, 333 Campus Drive, Stanford, CA, 94305, USA
- Laser Technology Laboratory, RIKEN, Wako, Saitama, 351-0198, Japan
| | - S P Moeller
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - M Mucke
- Department of Physics and Astronomy, Uppsala University, Box 516, SE-751 20, Uppsala, Sweden
| | - A Natan
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - R Obaid
- Department of Physics, University of Connecticut, 2152 Hillside Road, Storrs, CT, 06269, USA
| | - T Osipov
- Linac Coherent Light Source, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - O Plekan
- Elettra-Sincrotrone Trieste, Strada Statale 14-km 163,5 AREA Science Park, IT-34149, Basovizza, Trieste, Italy
| | - S Wang
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA
| | - H Koch
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA.
- Department of Chemistry, Norwegian University of Science and Technology, NO-7491, Trondheim, Norway.
| | - M Gühr
- Stanford PULSE Institute, SLAC National Accelerator Laboratory, 2575 Sand Hill Road, Menlo Park, CA, 94025, USA.
- Institut für Physik und Astronomie, Universität Potsdam, Karl-Liebknecht-Straße 24/25, DE-14476, Potsdam, Germany.
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Röder A, Humeniuk A, Giegerich J, Fischer I, Poisson L, Mitrić R. Femtosecond time-resolved photoelectron spectroscopy of the benzyl radical. Phys Chem Chem Phys 2017; 19:12365-12374. [PMID: 28453017 DOI: 10.1039/c7cp01437f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
We present a joint experimental and computational study of the nonradiative deactivation of the benzyl radical, C7H7, after UV excitation. Femtosecond time-resolved photoelectron imaging was applied to investigate the photodynamics of the radical. The experiments were accompanied by excited state dynamics simulations using surface hopping. Benzyl has been excited at 265 nm into the D-band (ππ*) and the dynamics was probed using probe wavelengths of 398 nm or 798 nm. At a probe wavelength of 398 nm a single time constant of around 70-80 fs was observed. When the dynamics was probed at 798 nm, a second time constant τ2 = 1.5 ps was visible, which can be attributed to further non-radiative deactivation to the lower-lying D1/D2 states.
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Affiliation(s)
- A Röder
- Institute of Physical and Theoretical Chemistry, University of Würzburg, Am Hubland, D-97074 Würzburg, Germany.
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40
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Vaissier V, Sakai VG, Li X, Cabral JT, Nelson J, Barnes PRF. How mobile are dye adsorbates and acetonitrile molecules on the surface of TiO 2 nanoparticles? A quasi-elastic neutron scattering study. Sci Rep 2016; 6:39253. [PMID: 27991538 PMCID: PMC5171786 DOI: 10.1038/srep39253] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2016] [Accepted: 11/22/2016] [Indexed: 01/01/2023] Open
Abstract
Motions of molecules adsorbed to surfaces may control the rate of charge transport within monolayers in systems such as dye sensitized solar cells. We used quasi-elastic neutron scattering (QENS) to evaluate the possible dynamics of two small dye moieties, isonicotinic acid (INA) and bis-isonicotinic acid (BINA), attached to TiO2 nanoparticles via carboxylate groups. The scattering data indicate that moieties are immobile and do not rotate around the anchoring groups on timescales between around 10 ps and a few ns (corresponding to the instrumental range). This gives an upper limit for the rate at which conformational fluctuations can assist charge transport between anchored molecules. Our observations suggest that if the conformation of larger dye molecules varies with time, it does so on longer timescales and/or in parts of the molecule which are not directly connected to the anchoring group. The QENS measurements also indicate that several layers of acetonitrile solvent molecules are immobilized at the interface with the TiO2 on the measurement time scale, in reasonable agreement with recent classical molecular dynamics results.
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Affiliation(s)
- Valerie Vaissier
- Department of Physcis, Imperial College London, London, SW72AZ, United Kingdom
- Centre for Plastics Electronics, Imperial College London, SW72AZ, United Kingdom
| | - Victoria Garcia Sakai
- ISIS Pulsed neutron and Muon Source, Rutherford Appleton Laboratory, Didcot, OX11 0QX, United Kingdom
| | - Xiaoe Li
- Department of Chemistry, Imperial College London, London, SW72AZ, United Kingdom
| | - João T. Cabral
- Centre for Plastics Electronics, Imperial College London, SW72AZ, United Kingdom
- Department of Chemical Engineering, Imperial College London, London, SW72AZ, United Kingdom
| | - Jenny Nelson
- Department of Physcis, Imperial College London, London, SW72AZ, United Kingdom
- Centre for Plastics Electronics, Imperial College London, SW72AZ, United Kingdom
| | - Piers R. F. Barnes
- Department of Physcis, Imperial College London, London, SW72AZ, United Kingdom
- Centre for Plastics Electronics, Imperial College London, SW72AZ, United Kingdom
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41
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Ruckenbauer M, Mai S, Marquetand P, González L. Revealing Deactivation Pathways Hidden in Time-Resolved Photoelectron Spectra. Sci Rep 2016; 6:35522. [PMID: 27762396 PMCID: PMC5071879 DOI: 10.1038/srep35522] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2016] [Accepted: 09/27/2016] [Indexed: 11/09/2022] Open
Abstract
Time-resolved photoelectron spectroscopy is commonly employed with the intention to monitor electronic excited-state dynamics occurring in a neutral molecule. With the help of theory, we show that when excited-state processes occur on similar time scales the different relaxation pathways are completely obscured in the total photoionization signal recorded in the experiment. Using non-adiabatic molecular dynamics and Dyson norms, we calculate the photoionization signal of cytosine and disentangle the transient contributions originating from the different deactivation pathways of its tautomers. In the simulations, the total signal from the relevant keto and enol tautomers can be decomposed into contributions either from the neutral electronic state populations or from the distinct mechanistic pathways across the multiple potential surfaces. The lifetimes corresponding to these contributions cannot be extracted from the experiment, thereby illustrating that new experimental setups are necessary to unravel the intricate non-adiabatic pathways occurring in polyatomic molecules after irradiation by light.
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Affiliation(s)
- Matthias Ruckenbauer
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
| | - Sebastian Mai
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
| | - Philipp Marquetand
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
| | - Leticia González
- Institute of Theoretical Chemistry, Faculty of Chemistry, University of Vienna, Währinger Str. 17, 1090 Vienna, Austria
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42
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Anstöter CS, Bull JN, Verlet JR. Ultrafast dynamics of temporary anions probed through the prism of photodetachment. INT REV PHYS CHEM 2016. [DOI: 10.1080/0144235x.2016.1203522] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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43
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Schalk O, Geng T, Thompson T, Baluyot N, Thomas RD, Tapavicza E, Hansson T. Cyclohexadiene Revisited: A Time-Resolved Photoelectron Spectroscopy and ab Initio Study. J Phys Chem A 2016; 120:2320-9. [DOI: 10.1021/acs.jpca.5b10928] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Oliver Schalk
- Department
of Chemical Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Ting Geng
- Department
of Chemical Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Travis Thompson
- Department
of Chemistry and Biochemistry, California State University, Long Beach, 1250 Bellflower Boulevard, Long Beach, California 90840-9507, United States
| | - Noel Baluyot
- Department
of Chemistry and Biochemistry, California State University, Long Beach, 1250 Bellflower Boulevard, Long Beach, California 90840-9507, United States
| | - Richard D. Thomas
- Department
of Chemical Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Enrico Tapavicza
- Department
of Chemistry and Biochemistry, California State University, Long Beach, 1250 Bellflower Boulevard, Long Beach, California 90840-9507, United States
| | - Tony Hansson
- Department
of Chemical Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
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44
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Yang J, Guehr M, Vecchione T, Robinson MS, Li R, Hartmann N, Shen X, Coffee R, Corbett J, Fry A, Gaffney K, Gorkhover T, Hast C, Jobe K, Makasyuk I, Reid A, Robinson J, Vetter S, Wang F, Weathersby S, Yoneda C, Centurion M, Wang X. Diffractive imaging of a rotational wavepacket in nitrogen molecules with femtosecond megaelectronvolt electron pulses. Nat Commun 2016; 7:11232. [PMID: 27046298 PMCID: PMC4822053 DOI: 10.1038/ncomms11232] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2015] [Accepted: 03/03/2016] [Indexed: 11/13/2022] Open
Abstract
Imaging changes in molecular geometries on their natural femtosecond timescale with sub-Angström spatial precision is one of the critical challenges in the chemical sciences, as the nuclear geometry changes determine the molecular reactivity. For photoexcited molecules, the nuclear dynamics determine the photoenergy conversion path and efficiency. Here we report a gas-phase electron diffraction experiment using megaelectronvolt (MeV) electrons, where we captured the rotational wavepacket dynamics of nonadiabatically laser-aligned nitrogen molecules. We achieved a combination of 100 fs root-mean-squared temporal resolution and sub-Angstrom (0.76 Å) spatial resolution that makes it possible to resolve the position of the nuclei within the molecule. In addition, the diffraction patterns reveal the angular distribution of the molecules, which changes from prolate (aligned) to oblate (anti-aligned) in 300 fs. Our results demonstrate a significant and promising step towards making atomically resolved movies of molecular reactions.
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Affiliation(s)
- Jie Yang
- Department of Physics and Astronomy, University of Nebraska-Lincoln, 855 N 16th Street, Lincoln, Nebraska 68588, USA
| | - Markus Guehr
- PULSE Institute, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
- Institute of Physics and Astronomy, Potsdam University, Potsdam 14476, Germany
| | | | - Matthew S. Robinson
- Department of Physics and Astronomy, University of Nebraska-Lincoln, 855 N 16th Street, Lincoln, Nebraska 68588, USA
| | - Renkai Li
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Nick Hartmann
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Xiaozhe Shen
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Ryan Coffee
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Jeff Corbett
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Alan Fry
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Kelly Gaffney
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Tais Gorkhover
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Carsten Hast
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Keith Jobe
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Igor Makasyuk
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Alexander Reid
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Joseph Robinson
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Sharon Vetter
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Fenglin Wang
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | | | - Charles Yoneda
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
| | - Martin Centurion
- Department of Physics and Astronomy, University of Nebraska-Lincoln, 855 N 16th Street, Lincoln, Nebraska 68588, USA
| | - Xijie Wang
- SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
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45
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Liu Y, Gerber T, Qin C, Jin F, Knopp G. Visualizing competing intersystem crossing and internal conversion with a complementary measurement. J Chem Phys 2016; 144:084201. [PMID: 26931694 DOI: 10.1063/1.4942124] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
A complementary measurement method based on a home-built double-sided velocity map imaging setup is introduced. This method can simultaneously obtain time-resolved photoelectron imaging and fragment ion imaging. It has been successfully applied to investigate the ultrafast dynamics of the second singlet electronically excited state (S2) in m-xylene. Time-resolved photoelectron and ion signals derived from the initial populated S2 state are tracked following two-photon absorption of a pump pulse. Time-of-flight mass spectra (TOFMS) show that there are dominant parent ions and one fragment ions with methyl loss during such a process. According to the measured photoelectron images and fragment ions images, transient kinetic energy distributions and angular distributions of the generated photoelectrons and fragments are obtained and analyzed. Compared to stand-alone photoelectron imaging, the obtained fragment ion imaging is powerful for further understanding the mechanisms especially when the dissociation occurs during the pump-probe ionization. Two competing channels intersystem crossing T3←S2 and internal conversion S1←S2 are attributed to the deactivation of the S2 state. A lifetime of ∼50 fs for the initially excited S2 state, of ∼276 fs for the secondary populated S1 state, and of 5.76 ps for the T3 state is inferred.
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Affiliation(s)
- Yuzhu Liu
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, People's Republic of China
| | | | - Chaochao Qin
- Henan Normal University, Xinxiang 453007, People's Republic of China
| | - Feng Jin
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology, Nanjing 210044, People's Republic of China
| | - Gregor Knopp
- Paul Scherrer Institute, 5232 Villigen, Switzerland
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46
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Brazard J, Bizimana LA, Gellen T, Carbery WP, Turner DB. Experimental Detection of Branching at a Conical Intersection in a Highly Fluorescent Molecule. J Phys Chem Lett 2016; 7:14-9. [PMID: 26647278 DOI: 10.1021/acs.jpclett.5b02476] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Conical intersections are molecular configurations at which adiabatic potential-energy surfaces touch. They are predicted to be ubiquitous, yet condensed-phase experiments have focused on the few systems with clear spectroscopic signatures of negligible fluorescence, high photoactivity, or femtosecond electronic kinetics. Although rare, these signatures have become diagnostic for conical intersections. Here we detect a coherent surface-crossing event nearly two picoseconds after optical excitation in a highly fluorescent molecule that has no photoactivity and nanosecond electronic kinetics. Time-frequency analysis of high-sensitivity measurements acquired using sub-8 fs pulses reveals phase shifts of the signal due to branching of the wavepacket through a conical intersection. The time-frequency analysis methodology demonstrated here on a model compound will enable studies of conical intersections in molecules that do not exhibit their diagnostic signatures. Improving the ability to detect conical intersections will enrich the understanding of their mechanistic role in molecular photochemistry.
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Affiliation(s)
- Johanna Brazard
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003, United States
| | - Laurie A Bizimana
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003, United States
| | - Tobias Gellen
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003, United States
| | - William P Carbery
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003, United States
| | - Daniel B Turner
- Department of Chemistry, New York University , 100 Washington Square East, New York, New York 10003, United States
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47
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Schalk O, Stenrup M, Geng T, Lindh R, Thomas RD, Feifel R, Hansson T. Influence of Alkoxy Groups on the Photoinduced Dynamics of Organic Molecules Exemplified on Alkyl Vinyl Ethers. J Phys Chem A 2015; 119:11105-12. [DOI: 10.1021/acs.jpca.5b06592] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- O. Schalk
- Department
of Chemical Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | | | - T. Geng
- Department
of Chemical Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | | | - R. D. Thomas
- Department
of Chemical Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - R. Feifel
- Department
of Physics, University of Gothenburg, Origovägen 6B, 412 96 Gothenburg, Sweden
| | - T. Hansson
- Department
of Chemical Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
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48
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Liu Y, Gerber T, Radi P, Knopp G. Ultrafast imaging of electronic relaxation in n-propylbenzene: Direct observation of intermediate state. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 149:54-58. [PMID: 25942085 DOI: 10.1016/j.saa.2015.04.050] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2015] [Revised: 04/13/2015] [Accepted: 04/16/2015] [Indexed: 06/04/2023]
Abstract
The ultrafast dynamics of the second singlet electronically excited state (S2) in n-propylbenzene has been investigated by femtosecond time-resolved photoelectron imaging coupled with photofragmentation spectroscopy. The intermediate state for the deactivation of the S2 state is observed by transient photoelectron kinetic energy distributions and photoelectron angular distributions. An ultrafast electronic relaxation process on timescale of the fitted ∼50 fs was observed in the S2 state by time-resolved photoelectron imaging and it is attributed to the S1←S2 internal conversion (IC). The time constant of 1.23 (±0.2) ps is determined for the further deactivation of the intermediate S1 state.
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Affiliation(s)
- Yuzhu Liu
- School of Physics and Optoelectronic Engineering, Nanjing University of Information Science & Technology, 210044 Nanjing, China.
| | | | - Peter Radi
- Paul Scherrer Institute, 5232 Villigen, Switzerland
| | - Gregor Knopp
- Paul Scherrer Institute, 5232 Villigen, Switzerland
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49
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Wilhelm MJ, Smith JM, Dai HL. Spectral reconstruction analysis for enhancing signal-to-noise in time-resolved spectroscopies. J Chem Phys 2015; 143:124204. [DOI: 10.1063/1.4931581] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Michael J. Wilhelm
- Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, Pennsylvania 19122, USA
| | - Jonathan M. Smith
- Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, Pennsylvania 19122, USA
| | - Hai-Lung Dai
- Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, Pennsylvania 19122, USA
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50
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Iikubo R, Fujiwara T, Sekikawa T, Harabuchi Y, Satoh S, Taketsugu T, Kayanuma Y. Time-Resolved Photoelectron Spectroscopy of Dissociating 1,2-Butadiene Molecules by High Harmonic Pulses. J Phys Chem Lett 2015; 6:2463-2468. [PMID: 26266720 DOI: 10.1021/acs.jpclett.5b00943] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Using 42 nm high harmonic pulses, the dissociation dynamics of 1,2-butadiene was investigated by time-resolved photoelectron spectroscopy (TRPES), enabling us to observe dynamical changes of multiple molecular orbitals (MOs) with higher temporal resolution than conventional light sources. Because each lower-lying occupied MO has particular spatial electron distribution, the structural dynamics of photochemical reaction can be revealed. On the femtosecond time scale, a short-lived excited state with a lifetime of 37 ± 15 fs and the coherent oscillation of the photoelectron yield stimulated by Hertzberg-Teller coupling were observed. Ab initio molecular dynamics simulations in the electronically excited state find three relaxation pathways from the vertically excited structure in S1 to the ground state, and one of them is the dominant relaxation pathway, observed as the short-lived excited state. On the picosecond time scale, the photoelectron yields related to the C-C bond decreased upon photoexcitation, indicating C-C bond cleavage.
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Affiliation(s)
- Ryo Iikubo
- †Department of Applied Physics, Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628, Japan
| | - Takehisa Fujiwara
- †Department of Applied Physics, Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628, Japan
| | - Taro Sekikawa
- †Department of Applied Physics, Faculty of Engineering, Hokkaido University, Kita 13 Nishi 8, Kita-ku, Sapporo 060-8628, Japan
| | - Yu Harabuchi
- ‡Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan
| | - Sota Satoh
- ‡Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan
| | - Tetsuya Taketsugu
- ‡Department of Chemistry, Faculty of Science, Hokkaido University, Kita 10 Nishi 8, Kita-ku, Sapporo 060-0810, Japan
| | - Yosuke Kayanuma
- §Materials and Structures Laboratory, Tokyo Institute of Technology, 4259 Nagatsuta, Midori-ku, Yokohama 226-8503, Japan
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