1
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Wang Y, Gu Z, Cao L, Zhang B, Zhang S. Channel Competition and Control of Relaxation Pathways in S 1 State of Acrolein: Role of Conical Intersection and Surface Crossing. J Phys Chem A 2023; 127:8595-8601. [PMID: 37801298 DOI: 10.1021/acs.jpca.3c05376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/07/2023]
Abstract
Channel competition and further photochemical control of relaxation pathways in excited molecules are of primary importance in photochemistry and related areas. Acrolein, as the simplest and most typical α,β-enone, is suitable to provide a model for understanding the photochemistry and photophysics of α,β-enones. Here, the ultrafast dynamics in acrolein following S1(nπ*) excitation has been studied by time-resolved photoelectron imaging (TRPEI) and mass spectroscopy. The competition between intersystem crossing (ISC) and internal conversion (IC) is investigated. The key factor influencing the decay pathways and the relative contributions are revealed to be the position of the excitation relative to the energy of the S1/S0 conical intersection (CI), which is obtained to be 3.65-3.76 eV experimentally. If the excitation is above the CI, IC is superior to ISC and most excited molecules go back to the ground. Otherwise, ISC will dominate the relaxation and lead the triplet products formation. These results show the potential of affecting the dynamics and governing the fate of excited molecules by adjusting the excitation conditions from the point of view of chemical control.
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Affiliation(s)
- Yanmei Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Zhenfei Gu
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Ling Cao
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Bing Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
| | - Song Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, P. R. China
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2
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Dergachev ID, Dergachev VD, Rooein M, Mirzanejad A, Varganov SA. Predicting Kinetics and Dynamics of Spin-Dependent Processes. Acc Chem Res 2023; 56:856-866. [PMID: 36926853 DOI: 10.1021/acs.accounts.2c00843] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
ConspectusPredicting mechanisms and rates of nonadiabatic spin-dependent processes including photoinduced intersystem crossings, thermally activated spin-forbidden reactions, and spin crossovers in metal centers is a very active field of research. These processes play critical roles in transition-metal-based and metalloenzymatic catalysis, molecular magnets, light-harvesting materials, organic light-emitting diodes, photosensitizers for photodynamic therapy, and many other applications. Therefore, accurate modeling of spin-dependent processes in complex systems and on different time scales is important for many problems in chemistry, biochemistry, and materials sciences.Nonadiabatic statistical theory (NAST) and nonadiabatic molecular dynamics (NAMD) are two complementary approaches to modeling the kinetics and dynamics of spin-dependent processes. NAST predicts the probabilities and rate constants of nonradiative transitions between electronic states with different spin multiplicities using molecular properties at only few critical points on the potential energy surfaces (PESs), including the reactant minimum and the minimum energy crossing point (MECP) between two spin states. This makes it possible to obtain molecular properties for NAST calculations using accurate but often computationally expensive electronic structure methods, which is critical for predicting the rate constants of spin-dependent processes. Alternatively, NAST can be used to study spin-dependent processes in very large complex molecular systems using less computationally expensive electronic structure methods. The nuclear quantum effects, such as zero-point vibrational energy, tunneling, and interference between reaction paths can be easily incorporated. However, the statistical and local nature of NAST makes it more suitable for large systems and slow kinetics. In contrast, NAMD explores entire PESs of interacting electronic states, making it ideal for modeling fast barrierless spin-dependent processes. Because the knowledge of large portions of PESs is often needed, the simulations require a very large number of electronic structure calculations, which limits the NAMD applicability to relatively small molecular systems and ultrafast kinetics.In this Account, we discuss our contribution to the development of the NAST and NAMD approaches for predicting the rates and mechanism of spin-dependent processes. First, we briefly describe our NAST and NAMD implementations. The NAST implementation is an extension of the transition state theory to the processes involving two crossing potential energy surfaces of different spin multiplicities. The NAMD approach includes the trajectory surface hopping (TSH) and ab initio multiple spawning (AIMS) methods. Second, we discuss several applications of NAST and NAMD to model spin-dependent processes in different systems. The NAST applicability to large complex systems is demonstrated by the studies of the spin-forbidden isomerization of the active sites of metal-sulfur proteins. Our implementation of the MECP search algorithm within the fully ab initio fragment molecular orbital method allows applying NAST to systems with thousands of atoms, such as the solvated protein rubredoxin. Applications of NAMD to ultrafast spin-dependent processes are represented by the generalized AIMS simulations utilizing the fast GPU-based TeraChem electronic structure program to gain insight into the complex photoexcited state relaxation in 2-cyclopentenone.
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Affiliation(s)
- Ilya D Dergachev
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557-0216, United States
| | - Vsevolod D Dergachev
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557-0216, United States
| | - Mitra Rooein
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557-0216, United States
| | - Amir Mirzanejad
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557-0216, United States
| | - Sergey A Varganov
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557-0216, United States
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3
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Jeremias N, Peschel MT, Jaschke C, de Vivie-Riedle R, Bach T. Photochemical Ring Contraction of 5,5-Dialkylcyclopent-2-enones and in situ Trapping by Primary Amines. J Org Chem 2022; 88:6294-6303. [PMID: 35786889 DOI: 10.1021/acs.joc.2c01156] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
If substituted in the 5,5-position, cyclopent-2-enones undergo a smooth photochemical rearrangement to ketenes. A concomitant cyclopropane formation occurs due to a 1,3-shift of the C5 carbon atom from the carbonyl carbon atom (C1) to carbon atom C3. In this study, the cyclopropyl-substituted ketene intermediates were trapped in situ by primary amines providing an efficient entry into 2,2-disubstituted cyclopropaneacetic amides (24 examples, 49-95% yield). A remarkable feature of the reaction is the fact that the photochemical rearrangement can occur from either the first excited singlet (S1) or the respective triplet state (T1). In line with experimental results (triplet quenching, sensitization), XMS-CASPT2 calculations support the existence of efficient reaction pathways to the intermediate ketene both on the singlet and on the triplet hypersurface.
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Affiliation(s)
- Noah Jeremias
- School of Natural Sciences, Department of Chemistry and Catalysis Research Center (CRC), Technical University of Munich, Lichtenbergstrasse 4, 85747 Garching, Germany
| | - Martin T Peschel
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 11, 81377 München, Germany
| | - Constantin Jaschke
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 11, 81377 München, Germany
| | - Regina de Vivie-Riedle
- Department Chemie, Ludwig-Maximilians-Universität München, Butenandtstrasse 11, 81377 München, Germany
| | - Thorsten Bach
- School of Natural Sciences, Department of Chemistry and Catalysis Research Center (CRC), Technical University of Munich, Lichtenbergstrasse 4, 85747 Garching, Germany
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4
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Guo F, Wang H, Ye X, Tan CH. Advanced Synthesis Using Photocatalysis Involved Dual Catalytic System. European J Org Chem 2022. [DOI: 10.1002/ejoc.202200326] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Fenfen Guo
- Zhejiang University of Technology College of Pharmaceutical Science CHINA
| | - Hong Wang
- Zhejiang University of Technology College of Pharmaceutical Science CHINA
| | - Xinyi Ye
- Zhejiang University of Technology College of Pharmaceutical Science 18 Chaowang Road 310014 Hangzhou CHINA
| | - Choon-Hong Tan
- Nanyang Technological University School of Physical and Mathematical Sciences SINGAPORE
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5
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Mukherjee S, Varganov SA. Intersystem crossing and internal conversion dynamics with GAIMS-TeraChem: Excited state relaxation in 2-cyclopentenone. J Chem Phys 2021; 155:174107. [PMID: 34742200 DOI: 10.1063/5.0068040] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Excited states relaxation in complex molecules often involves two types of nonradiative transitions, internal conversion (IC) and intersystem crossing (ISC). In the situations when the timescales of IC and ISC are comparable, an interplay between these two types of transitions can lead to complex nonadiabatic dynamics on multiple electronic states of different characters and spin multiplicities. We demonstrate that the generalized ab initio multiple spawning (GAIMS) method interfaced with the fast graphics processing unit-based TeraChem electronic structure code can be used to model such nonadiabatic dynamics involving both the IC and ISC transitions in molecules of moderate size. We carried out 1500 fs GAIMS simulations leading to the creation of up to 2500 trajectory basis functions to study the excited states relaxation in 2-cyclopentenone. After a vertical excitation from the ground state to the bright S2 state, the molecule quickly relaxes to the S1 state via conical intersection. The following relaxation proceeds along two competing pathways: one involves IC to the ground state, and the other is dominated by ISC to the low-lying triplet states. The time constants describing the population transfer between the six lowest singlet and triplet states predicted by the GAIMS dynamics are in good agreement with the characteristic times of IC and ISC obtained from the analysis of the time-resolved photoelectron spectrum.
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Affiliation(s)
- Saikat Mukherjee
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557-0216, USA
| | - Sergey A Varganov
- Department of Chemistry, University of Nevada, Reno, 1664 N. Virginia Street, Reno, Nevada 89557-0216, USA
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6
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Peschel MT, Kabaciński P, Schwinger DP, Thyrhaug E, Cerullo G, Bach T, Hauer J, Vivie‐Riedle R. Activation of 2‐Cyclohexenone by BF
3
Coordination: Mechanistic Insights from Theory and Experiment. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202016653] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Affiliation(s)
- Martin T. Peschel
- Department Chemie Ludwig-Maximilians-Universität München 81377 München Germany
| | - Piotr Kabaciński
- IFN-CNR and Dipartimento di Fisica Politecnico di Milano 20133 Milano Italy
| | - Daniel P. Schwinger
- Department of Chemistry and Catalysis Research Center (CRC) Technische Universität München 85747 Garching Germany
| | - Erling Thyrhaug
- Department of Chemistry and Catalysis Research Center (CRC) Technische Universität München 85747 Garching Germany
| | - Giulio Cerullo
- IFN-CNR and Dipartimento di Fisica Politecnico di Milano 20133 Milano Italy
| | - Thorsten Bach
- Department of Chemistry and Catalysis Research Center (CRC) Technische Universität München 85747 Garching Germany
| | - Jürgen Hauer
- Department of Chemistry and Catalysis Research Center (CRC) Technische Universität München 85747 Garching Germany
| | - Regina Vivie‐Riedle
- Department Chemie Ludwig-Maximilians-Universität München 81377 München Germany
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7
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Peschel MT, Kabaciński P, Schwinger DP, Thyrhaug E, Cerullo G, Bach T, Hauer J, de Vivie-Riedle R. Activation of 2-Cyclohexenone by BF 3 Coordination: Mechanistic Insights from Theory and Experiment. Angew Chem Int Ed Engl 2021; 60:10155-10163. [PMID: 33595902 PMCID: PMC8252487 DOI: 10.1002/anie.202016653] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2020] [Revised: 02/01/2021] [Indexed: 11/22/2022]
Abstract
Lewis acids have recently been recognized as catalysts enabling enantioselective photochemical transformations. Mechanistic studies on these systems are however rare, either due to their absorption at wavelengths shorter than 260 nm, or due to the limitations of theoretical dynamic studies for larger complexes. In this work, we overcome these challenges and employ sub-30-fs transient absorption in the UV, in combination with a highly accurate theoretical treatment on the XMS-CASPT2 level. We investigate 2-cyclohexenone and its complex to boron trifluoride and analyze the observed dynamics based on trajectory calculations including non-adiabatic coupling and intersystem crossing. This approach explains all ultrafast decay pathways observed in the complex. We show that the Lewis acid remains attached to the substrate in the triplet state, which in turn explains why chiral boron-based Lewis acids induce a high enantioselectivity in photocycloaddition reactions.
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Affiliation(s)
- Martin T Peschel
- Department Chemie, Ludwig-Maximilians-Universität München, 81377, München, Germany
| | - Piotr Kabaciński
- IFN-CNR and Dipartimento di Fisica, Politecnico di Milano, 20133, Milano, Italy
| | - Daniel P Schwinger
- Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Erling Thyrhaug
- Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Giulio Cerullo
- IFN-CNR and Dipartimento di Fisica, Politecnico di Milano, 20133, Milano, Italy
| | - Thorsten Bach
- Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Jürgen Hauer
- Department of Chemistry and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
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8
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Lee YR, Kim MH, Kwon CH. Probing the Photoionization Dynamics of 2-Cyclopenten-1-one via High-Resolution VUV-MATI Spectroscopy. J Phys Chem A 2021; 125:2356-2363. [PMID: 33724025 DOI: 10.1021/acs.jpca.1c01093] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
2-Cyclopenten-1-one (2CP), which is a cyclic enone, has been considered an important precursor because of its versatile functionality in the synthesis of natural products and materials for biofuels. Here, we report the adiabatic ionization energy (AIE) and cationic structure of 2CP in the ionic transition between the neutral S0 and the cationic D0 states probed by high-resolution vacuum ultraviolet mass-analyzed threshold ionization (VUV-MATI) spectroscopy. From the 0-0 band position in the VUV-MATI spectrum supported by the VUV-photoionization efficiency curve, the AIE of 2CP was determined to be 9.3477 ± 0.0004 eV (75,395 ± 3 cm-1), which is in good agreement with the reference value but much more accurate. The measured MATI spectrum combined with the Franck-Condon fitting at the B3LYP/cc-pVTZ level revealed that the cationic structure of 2CP is twisted with the C1 symmetry, whereas the neutral 2CP has the CS symmetry. The results indicate that geometrical changes induced by ionization are mainly attributed to the electron removal from the highest occupied molecular orbital, which consists of nonbonding orbitals on the oxygen atom in the carbonyl group interacting with the σ orbitals in the molecular plane of 2CP. Consequently, lowering the C1 symmetry for cationic 2CP led to the promotions of the ring-bending and ring-twisting modes in the MATI spectrum, which correspond to the ring puckering and C═C twisting in the S0 state, respectively.
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Affiliation(s)
- Yu Ran Lee
- New and Renewable Energy Research Center, Ewha Womans University, Seoul 03760, South Korea
| | - Myung Hwa Kim
- Department of Chemistry and Nanoscience, Ewha Womans University, Seoul 03760, South Korea
| | - Chan Ho Kwon
- Department of Chemistry, Kangwon National University, Chuncheon 24341, South Korea
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9
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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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10
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Tymann DC, Benedix L, Iovkova L, Pallach R, Henke S, Tymann D, Hiersemann M. Photochemical Approach to the Cyclohepta[b]indole Scaffold by Annulative Two-Carbon Ring-Expansion. Chemistry 2020; 26:11974-11978. [PMID: 32463529 PMCID: PMC7540574 DOI: 10.1002/chem.202002581] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2020] [Indexed: 12/12/2022]
Abstract
We report on the implementation of the concept of a photochemically elicited two-carbon homologation of a π-donor-π-acceptor substituted chromophore by triple-bond insertion. Implementing a phenyl connector between the slide-in module and the chromophore enabled the synthesis of cylohepta[b]indole-type building blocks by a metal-free annulative one-pot two-carbon ring expansion of the five-membered chromophore. Post-irradiative structural elaboration provided founding members of the indolo[2,3-d]tropone family of compounds. Control experiments in combination with computational chemistry on this multibond reorganization process founded the basis for a mechanistic hypothesis.
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Affiliation(s)
| | - Lars Benedix
- Fakultät für Chemie und Chemische BiologieTU Dortmund44227DortmundGermany
| | - Lyuba Iovkova
- Fakultät für Chemie und Chemische BiologieTU Dortmund44227DortmundGermany
| | - Roman Pallach
- Fakultät für Chemie und Chemische BiologieTU Dortmund44227DortmundGermany
| | - Sebastian Henke
- Fakultät für Chemie und Chemische BiologieTU Dortmund44227DortmundGermany
| | - David Tymann
- Fakultät für Chemie und Chemische BiologieTU Dortmund44227DortmundGermany
| | - Martin Hiersemann
- Fakultät für Chemie und Chemische BiologieTU Dortmund44227DortmundGermany
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11
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Geng T, Ehrmaier J, Schalk O, Richings GW, Hansson T, Worth G, Thomas RD. Time-Resolved Photoelectron Spectroscopy Studies of Isoxazole and Oxazole. J Phys Chem A 2020; 124:3984-3992. [PMID: 32242664 PMCID: PMC7304896 DOI: 10.1021/acs.jpca.9b11788] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
![]()
The
excited state relaxation pathways of isoxazole and oxazole
upon excitation with UV-light were investigated by nonadiabatic ab
initio dynamics simulations and time-resolved photoelectron spectroscopy.
Excitation of the bright ππ*-state of isoxazole predominantly
leads to ring-opening dynamics. Both the initially excited ππ*-state
and the dissociative πσ*-state offer a combined barrier-free
reaction pathway, such that ring-opening, defined as a distance of
more than 2 Å between two neighboring atoms, occurs within 45
fs. For oxazole, in contrast, the excited state dynamics is about
twice as slow (85 fs) and the quantum yield for ring-opening is lower.
This is caused by a small barrier between the ππ*-state
and the πσ*-state along the reaction path, which suppresses
direct ring-opening. Theoretical findings are consistent with the
measured time-resolved photoelectron spectra, confirming the timescales
and the quantum yields for the ring-opening channel. The results indicate
that a combination of time-resolved photoelectron spectroscopy and
excited state dynamics simulations can explain the dominant reaction
pathways for this class of molecules. As a general rule, we suggest
that the antibonding σ*-orbital located between the oxygen atom
and a neighboring atom of a five-membered heterocyclic system provides
a driving force for ring-opening reactions, which is modified by the
presence and position of additional nitrogen atoms.
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Affiliation(s)
- Ting Geng
- Department of Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Johannes Ehrmaier
- Department of Chemistry, Technical University of Munich, Lichtenbergstr. 4, 85748 Garching, Germany
| | - Oliver Schalk
- Department of Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden.,Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Gareth W Richings
- Department of Chemistry and Centre for Scientific Computing, University of Warwick, CV4 7AL Coventry, U.K
| | - Tony Hansson
- Department of Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Graham Worth
- Department of Chemistry, University College London, 20 Gordon Street, WC1H 0AJ London, U.K
| | - Richard D Thomas
- Department of Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
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12
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Schalk O, Galiana J, Geng T, Larsson TL, Thomas RD, Fdez. Galván I, Hansson T, Vacher M. Competition between ring-puckering and ring-opening excited state reactions exemplified on 5H-furan-2-one and derivatives. J Chem Phys 2020; 152:064301. [DOI: 10.1063/1.5129366] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Oliver Schalk
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - Joachim Galiana
- Department of Chemistry–Ångström Laboratory, Uppsala University, P.O. Box 538, SE-751 21 Uppsala, Sweden
- Department of Chemistry, École normale supérieure de Lyon, 69342 Lyon, France
| | - Ting Geng
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
| | - Tobias L. Larsson
- Department of Chemistry–Ångström Laboratory, Uppsala University, P.O. Box 538, SE-751 21 Uppsala, Sweden
| | - Richard D. Thomas
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
| | - Ignacio Fdez. Galván
- Department of Chemistry–Ångström Laboratory, Uppsala University, P.O. Box 538, SE-751 21 Uppsala, Sweden
- Department of Chemistry–BMC, Uppsala University, P.O. Box 576, SE-751 23 Uppsala, Sweden
| | - Tony Hansson
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
| | - Morgane Vacher
- Department of Chemistry–Ångström Laboratory, Uppsala University, P.O. Box 538, SE-751 21 Uppsala, Sweden
- Laboratoire CEISAM - UMR CNRS 6230, Université de Nantes, 44300 Nantes, France
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13
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Kotsina N, Candelaresi M, Saalbach L, Zawadzki MM, Crane SW, Sparling C, Townsend D. Short-wavelength probes in time-resolved photoelectron spectroscopy: an extended view of the excited state dynamics in acetylacetone. Phys Chem Chem Phys 2020; 22:4647-4658. [DOI: 10.1039/d0cp00068j] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Time-resolved photoelectron spectroscopy using a vacuum ultraviolet probe brings new insight to the excited state dynamics operating in acetylacetone.
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Affiliation(s)
- Nikoleta Kotsina
- Institute of Photonics & Quantum Sciences
- Heriot-Watt University
- Edinburgh
- UK
| | - Marco Candelaresi
- Institute of Photonics & Quantum Sciences
- Heriot-Watt University
- Edinburgh
- UK
| | - Lisa Saalbach
- Institute of Photonics & Quantum Sciences
- Heriot-Watt University
- Edinburgh
- UK
| | | | - Stuart W. Crane
- Institute of Photonics & Quantum Sciences
- Heriot-Watt University
- Edinburgh
- UK
| | - Chris Sparling
- 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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14
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Rowell KN, Kable SH, Jordan MJT. Structural Effects on the Norrish Type I α-Bond Cleavage of Tropospherically Important Carbonyls. J Phys Chem A 2019; 123:10381-10396. [DOI: 10.1021/acs.jpca.9b05534] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Keiran N. Rowell
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
| | - Scott H. Kable
- School of Chemistry, University of New South Wales, Sydney, New South Wales 2052, Australia
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15
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Zhu GZ, Cheung LF, Liu Y, Qian CH, Wang LS. Resonant Two-Photon Photoelectron Imaging and Intersystem Crossing from Excited Dipole-Bound States of Cold Anions. J Phys Chem Lett 2019; 10:4339-4344. [PMID: 31314535 DOI: 10.1021/acs.jpclett.9b01743] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
We report the observation of a dipole-bound state (DBS) 659 cm-1 below the electron detachment threshold of cryogenically cooled deprotonated 4,4'-biphenol anion (bPh-) and 19 of its lowest vibrational levels. Resonant two-photon photoelectron imaging (R2P-PEI) via the vibrational levels of the DBS displays a sharp peak with a constant binding energy. This observation indicates vertical detachment from the vibrational levels of the DBS to the corresponding neutral levels with the conservation of the vibrational energy, suggesting that the highly diffuse electron in the DBS has little effect on the neutral core. The R2P-PEI spectra also exhibit two features at lower binding energies, which come from intersystem crossings from the DBS to two lower-lying valence-bound triplet excited states of bPh-. The current study discloses the first R2P-PEI spectra from vibrational excited states of a DBS and direct spectroscopic evidence of transitions from a DBS to valence-bound states of anions.
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Affiliation(s)
- Guo-Zhu Zhu
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Ling Fung Cheung
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Yuan Liu
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Chen-Hui Qian
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
| | - Lai-Sheng Wang
- Department of Chemistry , Brown University , Providence , Rhode Island 02912 , United States
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16
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Poplata S, Bauer A, Storch G, Bach T. Intramolecular [2+2] Photocycloaddition of Cyclic Enones: Selectivity Control by Lewis Acids and Mechanistic Implications. Chemistry 2019; 25:8135-8148. [PMID: 30983074 PMCID: PMC6618137 DOI: 10.1002/chem.201901304] [Citation(s) in RCA: 38] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Indexed: 11/16/2022]
Abstract
The intramolecular [2+2] photocycloaddition of 3‐alkenyl‐2‐cycloalkenones was performed in an enantioselective fashion (nine representative examples, 54–86 % yield, 76–96 % ee) upon irradiation at λ=366 nm in the presence of an AlBr3‐activated oxazaborolidine as the Lewis acid. An extensive screening of proline‐derived oxazaborolidines showed that the enantioface differentiation depends strongly on the nature of the aryl group at the 3‐position of the heterocycle. DFT calculations of the Lewis acid–substrate complex indicate that attractive dispersion forces may be responsible for a change of the binding mode. The catalytic [2+2] photocycloaddition was shown to proceed on the triplet hypersurface with a quantum yield of 0.05. The positive effect of Lewis acids on the outcome of a given intramolecular [2+2] photocycloaddition was illustrated by optimizing the key step in a concise total synthesis of the sesquiterpene (±)‐italicene.
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Affiliation(s)
- Saner Poplata
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Andreas Bauer
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Golo Storch
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, 85747, Garching, Germany
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17
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Schalk O, Larsen MAB, Skov AB, Liisberg MB, Geng T, Sølling TI, Thomas RD. Time-Resolved Photoelectron Studies of Thiophene and 2,5-Dimethylthiophene. J Phys Chem A 2018; 122:8809-8818. [DOI: 10.1021/acs.jpca.8b06728] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- O. Schalk
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - M. A. B. Larsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - A. B. Skov
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - M. B. Liisberg
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - T. Geng
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
| | - T. I. Sølling
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen, Denmark
| | - R. D. Thomas
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
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18
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Schalk O, Geng T, Hansson T, Thomas RD. The ring-opening channel and the influence of Rydberg states on the excited state dynamics of furan and its derivatives. J Chem Phys 2018; 149:084303. [PMID: 30193494 DOI: 10.1063/1.5024655] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
One important relaxation pathway for photo-excited five-membered heterocyclic organic molecules is ring-opening via a dissociative πσ* state. In this study, we investigate the influence of this pathway in furan and several hydrogenated and methylated derivatives by combining time-resolved photoelectron spectroscopy with time-dependent density functional theory and coupled cluster calculations. We find strong experimental evidence that the ring-opening channel is the major relaxation channel in furan, 2,3-dihydrofuran, and 2-methylfuran (2-MF). In 2,5-dimethylfuran (25-DMF), however, we observe that the molecules relax either via a π3s Rydberg state or through a direct return to the ground state by undergoing ring-puckering motions. From the supporting calculations, for 2-MF and 25-DMF, we predict that there is strong mixing between the πσ* state and the π3s Rydberg state along the ring opening pathway. However, in 25-DMF, no crossing between the πσ*/π3s state and the initially excited ππ* state can be found along the ring opening coordinate, effectively blocking this channel.
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Affiliation(s)
- O Schalk
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
| | - T Geng
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
| | - T Hansson
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
| | - R D Thomas
- Department of Physics, AlbaNova University Center, Stockholm University, 106 91 Stockholm, Sweden
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19
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Rodrigues NDN, Staniforth M, Young JD, Peperstraete Y, Cole-Filipiak NC, Gord JR, Walsh PS, Hewett DM, Zwier TS, Stavros VG. Towards elucidating the photochemistry of the sunscreen filter ethyl ferulate using time-resolved gas-phase spectroscopy. Faraday Discuss 2018; 194:709-729. [PMID: 27711798 DOI: 10.1039/c6fd00079g] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultrafast time-resolved ion yield (TR-IY) and velocity map imaging spectroscopies are employed to reveal the relaxation dynamics after photoexcitation in ethyl 4-hydroxy-3-methoxycinnamate (ethyl ferulate, EF), an active ingredient in commercially available sunscreens. In keeping with a bottom-up strategy, the building blocks of EF, 2-methoxy-4-vinylphenol (MVP) and 4-hydroxy-3-methoxycinnamyl alcohol (coniferyl alcohol, ConA), were also studied to assist in our understanding of the dynamics of EF as we build up in molecular complexity. In contrast to the excited state dynamics of MVP and ConA, which are described by a single time constant (>900 ps), the dynamics of EF are described by three time constants (15 ± 4 ps, 148 ± 47 ps, and >900 ps). A mechanism is proposed involving internal conversion (IC) between the initially excited S1(11ππ*) and S2(11nπ*) states followed by intramolecular vibrational redistribution (IVR) on both states, in competition with intersystem crossing onto neighbouring triplet states (15 ± 4 ps). IVR and IC within the triplet manifold then ensues (148 ± 47 ps) to populate a low-lying triplet state (>900 ps). Importantly, the fluorescence spectrum of EF at the S1 origin, along with the associated lifetime (6.9 ± 0.1 ns), suggests that population is trapped, during initial IVR, on the S1(11ππ*) state. This serves to demonstrate the complex, competing dynamics in this sunscreen filter molecule.
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Affiliation(s)
- N D N Rodrigues
- University of Warwick, Department of Chemistry, CV4 7AL, Coventry, UK.
| | - M Staniforth
- University of Warwick, Department of Chemistry, CV4 7AL, Coventry, UK.
| | - J D Young
- University of Warwick, Department of Chemistry, CV4 7AL, Coventry, UK.
| | - Y Peperstraete
- University of Warwick, Department of Chemistry, CV4 7AL, Coventry, UK. and ENS de Cachan, 61 Avenue du Président Wilson, 94230, Cachan, France
| | - N C Cole-Filipiak
- University of Warwick, Department of Chemistry, CV4 7AL, Coventry, UK.
| | - J R Gord
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA
| | - P S Walsh
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA
| | - D M Hewett
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA
| | - T S Zwier
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, USA
| | - V G Stavros
- University of Warwick, Department of Chemistry, CV4 7AL, Coventry, UK.
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20
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Oesterling S, Schalk O, Geng T, Thomas RD, Hansson T, de Vivie-Riedle R. Substituent effects on the relaxation dynamics of furan, furfural and β-furfural: a combined theoretical and experimental approach. Phys Chem Chem Phys 2018; 19:2025-2035. [PMID: 28009022 DOI: 10.1039/c6cp06240g] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
For the series furan, furfural and β-furfural we investigated the effect of substituents and their positioning on the photoinduced relaxation dynamics in a combined theoretical and experimental approach. Using time resolved photoelectron spectroscopy with a high intensity probe pulse, we can, for the first time, follow the whole deactivation process of furan through a two photon probe signal. Using the extended 2-electron 2-orbital model [Nenov et al., J. Chem. Phys., 2011, 135, 034304] we explain the formation of one central conical intersection and predict the influence of the aldehyde group of the derivatives on its geometry. This, as well as the relaxation mechanisms from photoexcitation to the final outcome was investigated using a variety of theoretical methods. Complete active space self consistent field was used for on-the-fly calculations while complete active space perturbation theory and coupled cluster theory were used to accurately describe critical configurations. Experiment and theory show the relaxation dynamics of furfural and β-furfural to be slowed down, and together they disclose an additional deactivation pathway, which is attributed to the nO lonepair state introduced with the aldehyde group.
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Affiliation(s)
- Sven Oesterling
- Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany.
| | - Oliver Schalk
- Department of Physics, Stockholm University, AlbaNova University Centre, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Ting Geng
- Department of Physics, Stockholm University, AlbaNova University Centre, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Richard D Thomas
- Department of Physics, Stockholm University, AlbaNova University Centre, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Tony Hansson
- Department of Physics, Stockholm University, AlbaNova University Centre, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Regina de Vivie-Riedle
- Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstr. 5-13, 81377 München, Germany.
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21
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Soep B, Mestdagh JM, Briant M, Gaveau MA, Poisson L. Direct observation of slow intersystem crossing in an aromatic ketone, fluorenone. Phys Chem Chem Phys 2018; 18:22914-20. [PMID: 27485671 DOI: 10.1039/c6cp04308a] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Direct measurements of Single vibronic Level InterSystem Crossing (SLISC) have been performed on the fluorenone molecule in the gas phase, by time resolved photoelectron and photoion spectroscopy. Vibronic transitions above the S1 nπ* origin were excited in the 432-420 nm region and the decay of S1 and growth of T1(3)ππ* could be observed within a 10 ns time domain. The ionization potential is measured as 8.33 ± 0.04 eV. The energy of the first excited triplet state of fluorenone, T1 has been characterized directly at 18 640 ± 250 cm(-1). The internal conversion of S1 to S0 is found to amount to ∼15% of the population decay, thus ISC is the dominant electronic relaxation process. ISC, although favored by the S1(1)nπ*-T1(3)ππ* coupling scheme, is 3 orders of magnitude less efficient than in the similar molecule benzophenone. Thus, the planarity of the fluorenone molecule disfavors the exploration of the configuration space where surface crossings would create high ISC probability, which occurs in benzophenone through surface crossings. The time evolution of S1 fluorenone is well accounted for by the statistical decay of individual levels into a quasi-continuum of T1 vibronic levels.
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Affiliation(s)
- Benoît Soep
- Université Paris-Saclay, Bat 522 C.E.N. Saclay, F-91191 Gif-sur-Yvette Cedex, France.
| | - Jean-Michel Mestdagh
- Université Paris-Saclay, Bat 522 C.E.N. Saclay, F-91191 Gif-sur-Yvette Cedex, France.
| | - Marc Briant
- Université Paris-Saclay, Bat 522 C.E.N. Saclay, F-91191 Gif-sur-Yvette Cedex, France.
| | - Marc-André Gaveau
- Université Paris-Saclay, Bat 522 C.E.N. Saclay, F-91191 Gif-sur-Yvette Cedex, France.
| | - Lionel Poisson
- Université Paris-Saclay, Bat 522 C.E.N. Saclay, F-91191 Gif-sur-Yvette Cedex, France.
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22
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23
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Schalk O, Boguslavskiy AE. Anisotropy in Time-Resolved Photoelectron Spectroscopy in the Gas Phase. J Phys Chem A 2017; 121:9612-9618. [PMID: 29190096 DOI: 10.1021/acs.jpca.7b10490] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Transient absorption anisotropy is a well-established technique in time-resolved liquid phase spectroscopy. Here, we show how the technique is applied in the gas phase for time-resolved photoelectron spectroscopy and what type of additional information can be obtained as compared to other techniques. We exemplify its use by presenting results on rotational revivals in pyrazine after excitation at 324 nm and provide new insights into two recent experiments: (i) the difference between Rydberg and valence state excitation after one- and two-photon absorption in butadiene and (ii) excitation to the two lowest lying vibronic modes of the degenerate π3p Rydberg state in 1-azabicyclo[2.2.0]octane. Going forward, we expect the technique to be used on a regular basis, especially with the advent of high harmonic probe sources and liquid beam setups where other techniques to extract polarization-dependent information such as velocity map imaging cannot easily be applied.
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Affiliation(s)
- Oliver Schalk
- National Research Council Canada , 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.,Department of Physics, AlbaNova University Centre, Stockholm University , Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Andrey E Boguslavskiy
- National Research Council Canada , 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.,Department of Chemistry, University of Ottawa , 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
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24
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Bhattacherjee A, Pemmaraju CD, Schnorr K, Attar AR, Leone SR. Ultrafast Intersystem Crossing in Acetylacetone via Femtosecond X-ray Transient Absorption at the Carbon K-Edge. J Am Chem Soc 2017; 139:16576-16583. [DOI: 10.1021/jacs.7b07532] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Affiliation(s)
- Aditi Bhattacherjee
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Chaitanya Das Pemmaraju
- Theory
Institute for Materials and Energy Spectroscopies, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Kirsten Schnorr
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Andrew R. Attar
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Stephen R. Leone
- Department
of Chemistry, University of California, Berkeley, California 94720, United States
- Chemical
Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department
of Physics, University of California, Berkeley, California 94720, United States
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25
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Geng T, Schalk O, Neville SP, Hansson T, Thomas RD. Dynamics in higher lying excited states: Valence to Rydberg transitions in the relaxation paths of pyrrole and methylated derivatives. J Chem Phys 2017; 146:144307. [DOI: 10.1063/1.4979681] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ting Geng
- Department of Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Oliver Schalk
- Department of Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Simon P. Neville
- Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Tony Hansson
- Department of Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Richard D. Thomas
- Department of Physics, AlbaNova University Centre, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
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26
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Brenninger C, Pöthig A, Bach T. Brønsted Acid Catalysis in Visible-Light-Induced [2+2] Photocycloaddition Reactions of Enone Dithianes. Angew Chem Int Ed Engl 2017; 56:4337-4341. [PMID: 28319302 PMCID: PMC5396283 DOI: 10.1002/anie.201700837] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 02/09/2017] [Indexed: 12/15/2022]
Abstract
1,3-Dithiane-protected enones (enone dithianes) were found to undergo an intramolecular [2+2] photocycloaddition under visible-light irradiation (λ=405 nm) in the presence of a Brønsted acid (7.5-10 mol %). Key to the success of the reaction is presumably the formation of colored thionium ions, which are intermediates of the catalytic cycle. Cyclobutanes were thus obtained in very good yields (78-90 %). It is also shown that the dithiane moiety can be reductively or oxidatively removed without affecting the photochemically constructed ring skeleton.
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Affiliation(s)
- Christoph Brenninger
- Department Chemie and Catalysis Research Center (CRC)Technische Universität MünchenLichtenbergstrasse 485747GarchingGermany
| | - Alexander Pöthig
- Department Chemie and Catalysis Research Center (CRC)Technische Universität MünchenLichtenbergstrasse 485747GarchingGermany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC)Technische Universität MünchenLichtenbergstrasse 485747GarchingGermany
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27
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Brenninger C, Pöthig A, Bach T. Brønsted-Säure-Katalyse der [2+2]-Photocycloaddition von Enondithianen bei Bestrahlung mit sichtbarem Licht. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201700837] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Christoph Brenninger
- Department Chemie und Catalysis Research Center (CRC); Technische Universität München; Lichtenbergstr. 4 85747 Garching Deutschland
| | - Alexander Pöthig
- Department Chemie und Catalysis Research Center (CRC); Technische Universität München; Lichtenbergstr. 4 85747 Garching Deutschland
| | - Thorsten Bach
- Department Chemie und Catalysis Research Center (CRC); Technische Universität München; Lichtenbergstr. 4 85747 Garching Deutschland
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28
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MacDonell RJ, Schalk O, Geng T, Thomas RD, Feifel R, Hansson T, Schuurman MS. Excited state dynamics of acrylonitrile: Substituent effects at conical intersections interrogated via time-resolved photoelectron spectroscopy and ab initio simulation. J Chem Phys 2016. [DOI: 10.1063/1.4962170] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Ryan J. MacDonell
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, D’Iorio Hall, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Oliver Schalk
- Department of Physics, AlbaNova University Center, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Ting Geng
- Department of Physics, AlbaNova University Center, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Richard D. Thomas
- Department of Physics, AlbaNova University Center, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Raimund Feifel
- Department of Physics, University of Gothenburg, Origovägen 6B, 412 96 Gothenburg, Sweden
| | - Tony Hansson
- Department of Physics, AlbaNova University Center, Stockholm University, Roslagstullsbacken 21, 106 91 Stockholm, Sweden
| | - Michael S. Schuurman
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, D’Iorio Hall, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
- National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
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29
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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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30
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Champenois EG, Shivaram NH, Wright TW, Yang CS, Belkacem A, Cryan JP. Involvement of a low-lying Rydberg state in the ultrafast relaxation dynamics of ethylene. J Chem Phys 2016; 144:014303. [DOI: 10.1063/1.4939220] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Elio G. Champenois
- Graduate Group in Applied Science and Technology, University of California, Berkeley, California 94720, USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Niranjan H. Shivaram
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - Travis W. Wright
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Chemistry, University of California at Davis, Davis, California 95616, USA
| | - Chan-Shan Yang
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan
| | - Ali Belkacem
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
| | - James P. Cryan
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, USA
- PULSE Institute for Ultrafast Energy Science, SLAC National Accelerator Laboratory, Menlo Park, California 94025, USA
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31
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Neville SP, Wang Y, Boguslavskiy AE, Stolow A, Schuurman MS. Substituent effects on dynamics at conical intersections: Allene and methyl allenes. J Chem Phys 2016; 144:014305. [DOI: 10.1063/1.4938561] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Simon P. Neville
- Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
| | - Yanmei Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, People’s Republic of China
| | - Andrey E. Boguslavskiy
- Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
- National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa ON K1N 6N5, Canada
| | - Albert Stolow
- Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
- National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
- Department of Physics, University of Ottawa, 150 Louis Pasteur, Ottawa ON K1N 6N5, Canada
| | - Michael S. Schuurman
- Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario K1N 6N5, Canada
- National Research Council of Canada, 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
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32
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Cao J, Xie ZZ. Internal conversion and intersystem crossing in α,β-enones: a combination of electronic structure calculations and dynamics simulations. Phys Chem Chem Phys 2016; 18:6931-45. [DOI: 10.1039/c5cp06833a] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The geometrical constraint of the ring gives rise to a smaller spin–orbital coupling in the singlet–triplet crossing region, resulting in a lower intersystem crossing rate.
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Affiliation(s)
- Jun Cao
- Guizhou Provincial Key Laboratory of Computational Nano-material Science
- Guizhou Education University
- Guiyang
- China
- Guizhou Synergetic Innovation Center of Scientific Big Data for Advanced Manufacturing Technology
| | - Zhi-Zhong Xie
- Department of Chemistry
- School of Chemistry
- Chemical Engineering and Life Sciences
- Wuhan University of Technology
- Wuhan 430070
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Larsen MAB, Thøgersen J, Stephansen AB, Peon J, Sølling TI, Keiding SR. Transient IR Spectroscopic Observation of Singlet and Triplet States of 2-Nitrofluorene: Revisiting the Photophysics of Nitroaromatics. J Phys Chem A 2015; 120:28-35. [DOI: 10.1021/acs.jpca.5b09125] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Martin A. B. Larsen
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Jan Thøgersen
- Department
of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Anne B. Stephansen
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Jorge Peon
- Instituto
de Química, Universidad Nacional Autónoma de México, Circuito
Exterior, Ciudad Universitaria 04510, D.F. México
| | - Theis I. Sølling
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Søren R. Keiding
- Department
of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
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Falklöf O, Durbeej B, Norman P. Inter-Excited-State Phosphorescence in the Four-Component Relativistic Kohn–Sham Approximation: A Case Study on Lumiflavin. J Phys Chem A 2015; 119:11911-21. [DOI: 10.1021/acs.jpca.5b08908] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Affiliation(s)
- Olle Falklöf
- Division of Theoretical
Chemistry, IFM, Linköping University, SE-581 83 Linköping, Sweden
| | - Bo Durbeej
- Division of Theoretical
Chemistry, IFM, Linköping University, SE-581 83 Linköping, Sweden
| | - Patrick Norman
- Division of Theoretical
Chemistry, IFM, Linköping University, SE-581 83 Linköping, Sweden
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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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36
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Ernst HA, Wolf TJA, Schalk O, González-García N, Boguslavskiy AE, Stolow A, Olzmann M, Unterreiner AN. Ultrafast Dynamics of o-Nitrophenol: An Experimental and Theoretical Study. J Phys Chem A 2015; 119:9225-35. [PMID: 26266823 DOI: 10.1021/acs.jpca.5b04900] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The photolysis of o-nitrophenol (o-NP), a typical push-pull molecule, is of current interest in atmospheric chemistry as a possible source of nitrous acid (HONO). To characterize the largely unknown photolysis mechanism, the dynamics of the lowest lying excited singlet state (S1) of o-NP was investigated by means of femtosecond transient absorption spectroscopy in solution, time-resolved photoelectron spectroscopy (TRPES) in the gas phase and quantum chemical calculations. Evidence of the unstable aci-nitro isomer is provided both in the liquid and in the gas phase. Our results indicate that the S1 state displays strong charge transfer character, which triggers excited state proton transfer from the OH to the NO2 group as evidenced by a temporal shift of 20 fs of the onset of the photoelectron spectrum. The proton transfer itself is found to be coupled to an out-of-plane rotation of the newly formed HONO group, finally leading to a conical intersection between S1 and the ground state S0. In solution, return to S0 within 0.2-0.3 ps was monitored by stimulated emission. As a competitive relaxation channel, ultrafast intersystem crossing to the upper triplet manifold on a subpicosecond time scale occurs both in solution and in the gas phase. Due to the ultrafast singlet dynamics, we conclude that the much discussed HONO split-off is likely to take place in the triplet manifold.
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Affiliation(s)
- Hanna A Ernst
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany
| | - Thomas J A Wolf
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany.,Stanford PULSE Institute, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States
| | - Oliver Schalk
- AlbaNova University Centre, Stockholm University , Roslagstullsbacken 21, 10691 Stockholm, Sweden.,National Research Council of Canada , 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Núria González-García
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany
| | - Andrey E Boguslavskiy
- National Research Council of Canada , 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Albert Stolow
- National Research Council of Canada , 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.,Departments of Chemistry & Physics, University of Ottawa , 10 Marie Curie, Ottawa, Ontario K1N 6N5 Canada
| | - Matthias Olzmann
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany
| | - Andreas-Neil Unterreiner
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany
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37
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Chergui M. Empirical rules of molecular photophysics in the light of ultrafast spectroscopy. PURE APPL CHEM 2015. [DOI: 10.1515/pac-2014-0939] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
AbstractThe advent of ultrafast laser spectroscopy has allowed entirely new possibilities for the investigation of the ultrafast photophysics of inorganic metal-based molecular complexes. In this review we show different regimes where non-Kasha behavior shows up. We also demonstrate that while ultrafast intersystem crossing is a common observation in metal complexes, the ISC rates do not scale with the magnitude of the spin-orbit coupling constant. Structural dynamics and density of states play a crucial role in such ultrafast ISC processes, which are not limited to molecules containing heavy atoms.
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Affiliation(s)
- Majed Chergui
- 1Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie Ultrarapide, ISIC, Faculté des Sciences de Base, Station 6, CH-1015 Lausanne, Switzerland
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Abstract
The properties of transition metal complexes are interesting not only for their potential applications in solar energy conversion, OLEDs, molecular electronics, biology, photochemistry, etc. but also for their fascinating photophysical properties that call for a rethinking of fundamental concepts. With the advent of ultrafast spectroscopy over 25 years ago and, more particularly, with improvements in the past 10-15 years, a new area of study was opened that has led to insightful observations of the intramolecular relaxation processes such as internal conversion (IC), intersystem crossing (ISC), and intramolecular vibrational redistribution (IVR). Indeed, ultrafast optical spectroscopic tools, such as fluorescence up-conversion, show that in many cases, intramolecular relaxation processes can be extremely fast and even shorter than time scales of vibrations. In addition, more and more examples are appearing showing that ultrafast ISC rates do not scale with the magnitude of the metal spin-orbit coupling constant, that is, that there is no heavy-atom effect on ultrafast time scales. It appears that the structural dynamics of the system and the density of states play a crucial role therein. While optical spectroscopy delivers an insightful picture of electronic relaxation processes involving valence orbitals, the photophysics of metal complexes involves excitations that may be centered on the metal (called metal-centered or MC) or the ligand (called ligand-centered or LC) or involve a transition from one to the other or vice versa (called MLCT or LMCT). These excitations call for an element-specific probe of the photophysics, which is achieved by X-ray absorption spectroscopy. In this case, transitions from core orbitals to valence orbitals or higher allow probing the electronic structure changes induced by the optical excitation of the valence orbitals, while also delivering information about the geometrical rearrangement of the neighbor atoms around the atom of interest. With the emergence of new instruments such as X-ray free electron lasers (XFELs), it is now possible to perform ultrafast laser pump/X-ray emission probe experiments. In this case, one probes the density of occupied states. These core-level spectroscopies and other emerging ones, such as photoelectron spectroscopy of solutions, are delivering a hitherto unseen degree of detail into the photophysics of metal-based molecular complexes. In this Account, we will give examples of applications of the various methods listed above to address specific photophysical processes.
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Affiliation(s)
- Majed Chergui
- Ecole Polytechnique Fédérale de Lausanne, Laboratoire de Spectroscopie
Ultrarapide, ISIC, Faculté des Sciences de Base, Station 6, CH-1015 Lausanne, Switzerland
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Dean JC, Kusaka R, Walsh PS, Allais F, Zwier TS. Plant Sunscreens in the UV-B: Ultraviolet Spectroscopy of Jet-Cooled Sinapoyl Malate, Sinapic Acid, and Sinapate Ester Derivatives. J Am Chem Soc 2014; 136:14780-95. [PMID: 25295994 DOI: 10.1021/ja5059026] [Citation(s) in RCA: 97] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jacob C. Dean
- Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, United States
| | - Ryoji Kusaka
- Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, United States
| | - Patrick S. Walsh
- Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, United States
| | - Florent Allais
- AgroParisTech, Chaire Agro-Biotechnologies
Industrielles (ABI), 247
rue Paul Vaillant-Couturier, F-51100 Reims, France
- AgroParisTech, UMR 782 GMPA, Site de Grignon, F-78850 Thiverval-Grignon, France
- INRA, UMR 782 GMPA, Site de Grignon, F-78850 Thiverval-Grignon, France
| | - Timothy S. Zwier
- Department
of Chemistry, Purdue University, West Lafayette, Indiana 47907-2084, United States
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40
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Wolf TJA, Kuhlman TS, Schalk O, Martínez TJ, Møller KB, Stolow A, Unterreiner AN. Hexamethylcyclopentadiene: time-resolved photoelectron spectroscopy and ab initio multiple spawning simulations. Phys Chem Chem Phys 2014; 16:11770-9. [DOI: 10.1039/c4cp00977k] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Time-resolved photoelectron spectroscopy and ab initio multiple spawning dynamical simulations of hexamethylcyclopentadiene reveal wavepacket evolution in a distinct degree of freedom.
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Affiliation(s)
- T. J. A. Wolf
- Institut für Physikalische Chemie and Center for Functional Nanostructures (CFN)
- Karlsruhe Institute of Technology (KIT)
- 76131 Karlsruhe, Germany
- Stanford PULSE Institute
- Menlo Park, USA
| | - T. S. Kuhlman
- Department of Chemistry
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - O. Schalk
- Stockholm University
- AlbaNova University Center
- , Sweden
- National Research Council
- , Canada
| | - T. J. Martínez
- Stanford PULSE Institute
- Menlo Park, USA
- Department of Chemistry
- Stanford University
- Stanford, USA
| | - K. B. Møller
- Department of Chemistry
- Technical University of Denmark
- DK-2800 Kgs. Lyngby, Denmark
| | - A. Stolow
- National Research Council
- , Canada
- Department of Chemistry
- University of Ottawa
- Canada
| | - A.-N. Unterreiner
- Institut für Physikalische Chemie and Center for Functional Nanostructures (CFN)
- Karlsruhe Institute of Technology (KIT)
- 76131 Karlsruhe, Germany
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