1
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Kumar A, Malevich P, Mewes L, Wu S, Barham JP, Hauer J. Transient absorption spectroscopy based on uncompressed hollow core fiber white light proves pre-association between a radical ion photocatalyst and substrate. J Chem Phys 2023; 158:144201. [PMID: 37061463 DOI: 10.1063/5.0142225] [Citation(s) in RCA: 9] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/17/2023] Open
Abstract
We present a hollow-core fiber (HCF) based transient absorption experiment, with capabilities beyond common titanium:sapphire based setups. By spectral filtering of the HCF spectrum, we provide pump pulses centered at 425 nm with several hundred nJ of pulse energy at the sample position. By employing the red edge of the HCF output for seeding CaF2, we obtain smooth probing spectra in the range between 320 and 900 nm. We demonstrate the capabilities of our experiment by following the ultrafast relaxation dynamics of a radical cationic photocatalyst to prove its pre-association with an arene substrate, a phenomenon that was not detectable previously by steady-state spectroscopic techniques. The detected preassembly rationalizes the successful participation of radical ionic photocatalysts in single electron transfer reactions, a notion that has been subject to controversy in recent years.
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Affiliation(s)
- Ajeet Kumar
- Department of Chemistry and Catalysis Research Center (CRC), School of Natural Sciences, Technical University of Munich, 85748 Garching, Germany
| | - Pavel Malevich
- Department of Chemistry and Catalysis Research Center (CRC), School of Natural Sciences, Technical University of Munich, 85748 Garching, Germany
| | - Lars Mewes
- Department of Chemistry and Catalysis Research Center (CRC), School of Natural Sciences, Technical University of Munich, 85748 Garching, Germany
| | - Shangze Wu
- Universität Regensburg, Fakultät für Chemie und Pharmazie, 93040 Regensburg, Germany
| | - Joshua P Barham
- Universität Regensburg, Fakultät für Chemie und Pharmazie, 93040 Regensburg, Germany
| | - Jürgen Hauer
- Department of Chemistry and Catalysis Research Center (CRC), School of Natural Sciences, Technical University of Munich, 85748 Garching, Germany
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2
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Wilcken R, Gerwien A, Huber LA, Dube H, Riedle E. Quantitative
In‐Situ
NMR Illumination for Excitation and Kinetic Analysis of Molecular Motor Intermediates. CHEMPHOTOCHEM 2022. [DOI: 10.1002/cptc.202100232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Roland Wilcken
- Lehrstuhl für BioMolekulare Optik Ludwig-Maximilians-Universität München Oettingenstr. 67 80538 München Germany
- Chair of Organic Chemistry I Friedrich-Alexander-Universität Erlangen-Nürnberg Department of Chemistry and Pharmacy Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Aaron Gerwien
- Department Chemie Ludwig-Maximilians-Universität München Butenandtstr. 5–13 (Haus F) 81377 München Germany
| | - Ludwig Alexander Huber
- Department Chemie Ludwig-Maximilians-Universität München Butenandtstr. 5–13 (Haus F) 81377 München Germany
| | - Henry Dube
- Department Chemie Ludwig-Maximilians-Universität München Butenandtstr. 5–13 (Haus F) 81377 München Germany
- Chair of Organic Chemistry I Friedrich-Alexander-Universität Erlangen-Nürnberg Department of Chemistry and Pharmacy Nikolaus-Fiebiger-Str. 10 91058 Erlangen Germany
| | - Eberhard Riedle
- Lehrstuhl für BioMolekulare Optik Ludwig-Maximilians-Universität München Oettingenstr. 67 80538 München Germany
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3
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Marčiulionytė V, Jukna V, Tamošauskas G, Dubietis A. High repetition rate green-pumped supercontinuum generation in calcium fluoride. Sci Rep 2021; 11:15019. [PMID: 34294792 PMCID: PMC8298603 DOI: 10.1038/s41598-021-94411-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2021] [Accepted: 07/12/2021] [Indexed: 11/24/2022] Open
Abstract
We compare supercontinuum generation in \documentclass[12pt]{minimal}
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\begin{document}$$\hbox {CaF}_2$$\end{document}CaF2 crystal under tight and loose focusing of 150 fs, 515 nm second harmonic pulses from an amplified Yb:KGW laser at a repetition rate of 10 kHz. It is demonstrated that supercontinuum generation geometry applying loose focusing (\documentclass[12pt]{minimal}
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\begin{document}$$\hbox {NA}=0.004$$\end{document}NA=0.004) of the pump beam into a long (25 mm) \documentclass[12pt]{minimal}
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\begin{document}$$\hbox {CaF}_2$$\end{document}CaF2 sample is advantageous in terms of supercontinuum spectral extent and durability of damage-free operation of the nonlinear material as compared to a commonly used supercontinuum generation setup which employs tight focusing (\documentclass[12pt]{minimal}
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\begin{document}$$\hbox {NA}=0.012$$\end{document}NA=0.012) into a short (5 mm) sample and to setup which uses tight focusing into a long (25 mm) sample. More specifically, loose focusing into a long sample showed remarkably longer (20 min) damage-free operation of the nonlinear material, which was not translated with respect of the pump beam, while in tight focusing condition the sample is damaged just within 2 min of operation, leading to a complete extinction of the supercontinuum spectrum. The evolution of optical degradation of the nonlinear material in time and its impact to supercontinuum spectrum is studied in terms of filament-induced luminescence due to self-trapped exciton emission and light scattering at the pump wavelength indicating the onset of optical damage. Our findings are supported by the numerical simulations which compare relevant parameters related to filament propagation in tight and loose focusing conditions.
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Affiliation(s)
- Vaida Marčiulionytė
- Laser Research Center, Vilnius University, Saulėtekio Avenue 10, LT, 10223, Vilnius, Lithuania
| | - Vytautas Jukna
- Laser Research Center, Vilnius University, Saulėtekio Avenue 10, LT, 10223, Vilnius, Lithuania
| | - Gintaras Tamošauskas
- Laser Research Center, Vilnius University, Saulėtekio Avenue 10, LT, 10223, Vilnius, Lithuania
| | - Audrius Dubietis
- Laser Research Center, Vilnius University, Saulėtekio Avenue 10, LT, 10223, Vilnius, Lithuania.
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4
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Lauenstein R, Mader SL, Derondeau H, Esezobor OZ, Block M, Römer AJ, Jandl C, Riedle E, Kaila VRI, Hauer J, Thyrhaug E, Hess CR. The central role of the metal ion for photoactivity: Zn- vs. Ni-Mabiq. Chem Sci 2021; 12:7521-7532. [PMID: 34163843 PMCID: PMC8171322 DOI: 10.1039/d0sc06096h] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Photoredox catalysts are integral components of artificial photosystems, and have recently emerged as powerful tools for catalysing numerous organic reactions. However, the development of inexpensive and efficient earth-abundant photoredox catalysts remains a challenge. We here present the photochemical and photophysical properties of a Ni–Mabiq catalyst ([NiII(Mabiq)]OTf (1); Mabiq = 2-4:6-8-bis(3,3,4,4-tetramethyldihydropyrrolo)-10-15-(2,2-biquinazolino)-[15]-1,3,5,8,10,14-hexaene1,3,7,9,11,14-N6)—and of a Zn-containing analogue ([ZnII(Mabiq)OTf] (2))—using steady state and time resolved optical spectroscopy, time-dependent density functional theory (TDDFT) calculations, and reactivity studies. The Ni and Zn complexes exhibit similar absorption spectra, but markedly different photochemical properties. These differences arise because the excited states of 2 are ligand-localized, whereas metal-centered states account for the photoactivity of 1. The distinct properties of the Ni and Zn complexes are manifest in their behavior in the photo-driven aza-Henry reaction and oxidative coupling of methoxybenzylamine. The development of earth-abundant photoredox catalysts remains a challenge. Studies of Ni- and Zn-Mabiq complexes demonstrate how the coordinating metal ion influences the photochemistry, photodynamics and reactivity of photocatalysts.![]()
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Affiliation(s)
- Raphael Lauenstein
- Department of Chemistry and Catalysis Research Center, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
| | - Sophie L Mader
- Department of Chemistry, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
| | - Henrieta Derondeau
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München Oettingenstr. 67 80538 Munich Germany
| | - Oaikhena Z Esezobor
- Department of Chemistry and Catalysis Research Center, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
| | - Matthias Block
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München Oettingenstr. 67 80538 Munich Germany
| | - Armin J Römer
- Department of Chemistry, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
| | - Christian Jandl
- Department of Chemistry and Catalysis Research Center, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
| | - Eberhard Riedle
- Lehrstuhl für BioMolekulare Optik, Fakultät für Physik, Ludwig-Maximilians-Universität München Oettingenstr. 67 80538 Munich Germany
| | - Ville R I Kaila
- Department of Chemistry, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
| | - Jürgen Hauer
- Department of Chemistry and Catalysis Research Center, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
| | - Erling Thyrhaug
- Department of Chemistry and Catalysis Research Center, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
| | - Corinna R Hess
- Department of Chemistry and Catalysis Research Center, Technical University of Munich Lichtenbergstr. 4, 85747 Garching Germany
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5
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Zhou Y, Gurzadyan GG, Ni W, Gelin MF, Sun L. Upper Excited State Photophysics of Malachite Green in Solution and Films. J Phys Chem B 2020; 124:4293-4302. [PMID: 32366105 DOI: 10.1021/acs.jpcb.0c01737] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Relaxation pathways of upper excited electronic states of malachite green (MG) in ethanol and in films are studied by steady-state and time-resolved spectroscopic techniques. In contrast to ethanol, where MG emits weak short-lived spectrally well separated S2 and S1 fluorescence with the lifetimes ∼0.3 and ∼0.9 ps, MG films show a much stronger broadband fluorescence within 430-700 nm, revealing multiexponential kinetics with the characteristic decay times τ1 ≈ 1 ps, τ2 ≈ 10 ps, τ3 ≈ 0.05-0.8 ns, and τ4 ≈ 2-3 ns. By the analysis of spectroscopic responses of MG in ethanol and in films as well as by theoretical modeling, we demonstrate that significant increase of fluorescence lifetimes and substantial enhancement of fluorescence intensity in MG films are stipulated by the decrease of efficiency of the S2 → S1 and S1 → S0 internal conversion, which in turn is caused by hindrance of rotation of MG's phenyl rings controlling the S2/S1 and S1/S0 conical intersections. These findings indicate that MG films may become promising non-Kasha materials (with reasonable S2 emission) with numerous photophysical and photochemical applications.
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Affiliation(s)
- Yichen Zhou
- State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, Dalian University of Technology, 116024 Dalian, China
| | - Gagik G Gurzadyan
- State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, Dalian University of Technology, 116024 Dalian, China
| | - Wenjun Ni
- State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, Dalian University of Technology, 116024 Dalian, China
| | - Maxim F Gelin
- School of Sciences, Hangzhou Dianzi University, 310018 Hangzhou, China
| | - Licheng Sun
- State Key Laboratory of Fine Chemicals, Institute of Artificial Photosynthesis, Dalian University of Technology, 116024 Dalian, China.,Department of Chemistry, School of Engineering Sciences in Chemistry, Biotechnology and Health, KTH Royal Institute of Technology, 10044 Stockholm, Sweden
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6
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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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7
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Adamu AI, Habib MS, Petersen CR, Lopez JEA, Zhou B, Schülzgen A, Bache M, Amezcua-Correa R, Bang O, Markos C. Deep-UV to Mid-IR Supercontinuum Generation driven by Mid-IR Ultrashort Pulses in a Gas-filled Hollow-core Fiber. Sci Rep 2019; 9:4446. [PMID: 30872762 PMCID: PMC6418117 DOI: 10.1038/s41598-019-39302-2] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2018] [Accepted: 01/21/2019] [Indexed: 11/09/2022] Open
Abstract
Supercontinuum (SC) generation based on ultrashort pulse compression constitutes one of the most promising technologies towards ultra-wide bandwidth, high-brightness, and spatially coherent light sources for applications such as spectroscopy and microscopy. Here, multi-octave SC generation in a gas-filled hollow-core antiresonant fiber (HC-ARF) is reported spanning from 200 nm in the deep ultraviolet (DUV) to 4000 nm in the mid-infrared (mid-IR) having an output energy of 5 μJ. This was obtained by pumping at the center wavelength of the first anti-resonant transmission window (2460 nm) with ~100 fs pulses and an injected pulse energy of ~8 μJ. The mechanism behind the extreme spectral broadening relies upon intense soliton-plasma nonlinear dynamics which leads to efficient soliton self-compression and phase-matched dispersive wave (DW) emission in the DUV region. The strongest DW is observed at 275 nm which corresponds to the calculated phase-matching wavelength of the pump. Furthermore, the effect of changing the pump pulse energy and gas pressure on the nonlinear dynamics and their direct impact on SC generation was investigated. This work represents another step towards gas-filled fiber-based coherent sources, which is set to have a major impact on applications spanning from DUV to mid-IR.
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Affiliation(s)
- Abubakar I Adamu
- DTU Fotonik, Technical University of Denmark, Kgs., DK, 2800, Lyngby, Denmark.
| | - Md Selim Habib
- CREOL, The College of Optics and Photonics, University of Central Florida, FL, 32816, Orlando, USA
| | | | - J Enrique Antonio Lopez
- CREOL, The College of Optics and Photonics, University of Central Florida, FL, 32816, Orlando, USA
| | - Binbin Zhou
- DTU Fotonik, Technical University of Denmark, Kgs., DK, 2800, Lyngby, Denmark
| | - Axel Schülzgen
- CREOL, The College of Optics and Photonics, University of Central Florida, FL, 32816, Orlando, USA
| | - Morten Bache
- DTU Fotonik, Technical University of Denmark, Kgs., DK, 2800, Lyngby, Denmark
| | - Rodrigo Amezcua-Correa
- CREOL, The College of Optics and Photonics, University of Central Florida, FL, 32816, Orlando, USA
| | - Ole Bang
- DTU Fotonik, Technical University of Denmark, Kgs., DK, 2800, Lyngby, Denmark
| | - Christos Markos
- DTU Fotonik, Technical University of Denmark, Kgs., DK, 2800, Lyngby, Denmark.
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8
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Kearns NM, Jones AC, Kunz MB, Allen RT, Flach JT, Zanni MT. Two-Dimensional White-Light Spectroscopy Using Supercontinuum from an All-Normal Dispersion Photonic Crystal Fiber Pumped by a 70 MHz Yb Fiber Oscillator. J Phys Chem A 2019; 123:3046-3055. [DOI: 10.1021/acs.jpca.9b02206] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Nicholas M. Kearns
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Andrew C. Jones
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Miriam Bohlmann Kunz
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Ryan T. Allen
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Jessica T. Flach
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Martin T. Zanni
- Department of Chemistry, University of Wisconsin—Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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9
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Letrun R, Lang B, Yushchenko O, Wilcken R, Svechkarev D, Kolodieznyi D, Riedle E, Vauthey E. Excited-state dynamics of a molecular dyad with two orthogonally-oriented fluorophores. Phys Chem Chem Phys 2018; 20:30219-30230. [PMID: 30489576 DOI: 10.1039/c8cp05356a] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
The excited-state dynamics of a T-shaped bichromophoric molecule, consisting of two strong fluorophores, diphenyloxazole and diphenylpyrazoline, directly linked in an orthogonal geometry, was investigated. Despite the weak coupling ensured by this geometry and confirmed by the electronic absorption spectra, this dyad exhibits only weak fluorescence in both apolar and polar solvents, with fluorescence lifetimes ranging from 200 ps in CHX to 10 ps in ACN. Ultrafast spectroscopic measurements reveal that the fluorescence quenching in polar solvents is due to the population of a charge-separated state. In non-polar solvents, this process is energetically not feasible, and a quenching due to an efficient intersystem crossing (ISC) to the triplet manifold is proposed, based on quantum-chemical calculations. This process occurs via the spin-orbit charge-transfer (SOCT) ISC mechanism, which is enabled by the charge-transfer character acquired by the S1 state of the dyad upon structural relaxation and by the orthogonal arrangement of the molecular orbitals involved in the transition. The same mechanism is proposed to explain why the recombination of the charge-separated state is faster in medium than in highly polar solvents, as well as to account for the fast decay of the lowest triplet state to the ground state.
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Affiliation(s)
- Romain Letrun
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest-Ansermet, CH-1211 Geneva 4, Switzerland.
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10
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Schüppel F, Roos MK, de Vivie-Riedle R. Ultrafast non-adiabatic dynamics of excited diphenylmethyl bromide elucidated by quantum dynamics and semi-classical on-the-fly dynamics. Phys Chem Chem Phys 2018; 20:22753-22761. [PMID: 30140797 DOI: 10.1039/c8cp03257b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Carbocations and carboradicals are key intermediates in organic chemistry. Typically UV laser excitation is used to induce homolytical or heterolytical bond cleavage in suitable precursor molecules. Of special interest hereby are diphenylmethyl compounds (Ph2CH-X) with X = Cl, Br as a leaving group as they form diphenylmethyl radicals (Ph2CH˙) and cations (Ph2CH+) within a femtosecond time scale in polar solvents. In this work, we build on our methodology developed for the chlorine case and investigate the photodissociation reaction of Ph2CH-Br by state-of-the-art theoretical methods. On the one hand, we employ specially adapted reactive coordinates for a grid-based wave packet dynamics in reduced dimensionality using the Wilson G-matrix ansatz for the kinetic part of the Hamiltonian. On the other hand, we use full-dimensional semiclassical on-the-fly dynamics with Tully's fewest switches surface hopping routine for comparison. We apply both methods to explain remarkable differences in experimental transient absorption measurements for Cl or Br as the leaving group. The wave packet motion, visible only for the bromine leaving group, can be related to the crucial role of the central carbon atom, which undergoes rehybridization from sp3 to sp2 during the photoinduced bond cleavage. Comparable features are the two consecutive conical intersections near the Franck-Condon region controlling the product splitting to Ph2CH˙/Br˙ and Ph2CH+/Br- as well as the difference in delay time for the respective product formation.
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Affiliation(s)
- Franziska Schüppel
- Department of Chemistry, Ludwig-Maximilians-Universität München, Butenandtstraße 5-13, 81377 Munich, Germany.
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11
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Lang B. Photometrics of ultrafast and fast broadband electronic transient absorption spectroscopy: State of the art. THE REVIEW OF SCIENTIFIC INSTRUMENTS 2018; 89:093112. [PMID: 30278696 DOI: 10.1063/1.5039457] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Accepted: 08/30/2018] [Indexed: 06/08/2023]
Abstract
The physical limits of the photometric resolution in broadband electronic transient absorption spectroscopy are discussed together with solutions for how to reach these limits in practice. In the first part, quantitative expressions for the noise contributions to the transient absorption signal are derived and experimentally tested. Experimental approaches described in the literature are discussed and compared on this basis. Guide-lines for designing a setup are established. In the second part, a method for obtaining nearly shot-noise limited kinetics with photometric resolution of the order of 100 μOD in overall measurement times of a few minutes from femtosecond to microsecond time scale is presented. The results are discussed in view of other experiments of step-scan type which are subject to a background or to correlated noise. Finally, detailed information is provided on how to obtain transient absorption spectra where counting statistics are the sole source of noise. A method for how to suppress outliers without introducing bias is discussed. An application example is given to demonstrate the achievable signal-to-noise level and the fast acquisition time.
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Affiliation(s)
- Bernhard Lang
- Department of Physical Chemistry, University of Geneva, 30 Quai Ernest Ansermet, CH-1211 Genève 4, Switzerland
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12
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Ultraviolet Transient Absorption Spectrometer with Sub-20-fs Time Resolution. APPLIED SCIENCES-BASEL 2018. [DOI: 10.3390/app8060989] [Citation(s) in RCA: 38] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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13
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Abstract
The dynamics of chemical reactions in liquid solutions are now amenable to direct study using ultrafast laser spectroscopy techniques and advances in computer simulation methods. The surrounding solvent affects the chemical reaction dynamics in numerous ways, which include: (i) formation of complexes between reactants and solvent molecules; (ii) modifications to transition state energies and structures relative to the reactants and products; (iii) coupling between the motions of the reacting molecules and the solvent modes, and exchange of energy; (iv) solvent caging of reactants and products; and (v) structural changes to the solvation shells in response to the changing chemical identity of the solutes, on timescales which may be slower than the reactive events. This article reviews progress in the study of bimolecular chemical reaction dynamics in solution, concentrating on reactions which occur on ground electronic states. It illustrates this progress with reference to recent experimental and computational studies, and considers how the various ways in which a solvent affects the chemical reaction dynamics can be unravelled. Implications are considered for research in fields such as mechanistic synthetic chemistry.
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Affiliation(s)
- Andrew J Orr-Ewing
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, UK.
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14
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Kowalewski M, Fingerhut BP, Dorfman KE, Bennett K, Mukamel S. Simulating Coherent Multidimensional Spectroscopy of Nonadiabatic Molecular Processes: From the Infrared to the X-ray Regime. Chem Rev 2017; 117:12165-12226. [DOI: 10.1021/acs.chemrev.7b00081] [Citation(s) in RCA: 81] [Impact Index Per Article: 11.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
Affiliation(s)
- Markus Kowalewski
- Department
of Chemistry and Department of Physics and Astronomy, University of California, Irvine, California 92697-2025, United States
| | - Benjamin P. Fingerhut
- Max-Born-Institut für Nichtlineare Optik und Kurzzeitspektroskopie, D-12489 Berlin, Germany
| | - Konstantin E. Dorfman
- State
Key Laboratory of Precision Spectroscopy, East China Normal University, Shanghai 200062, China
| | - Kochise Bennett
- Department
of Chemistry and Department of Physics and Astronomy, University of California, Irvine, California 92697-2025, United States
| | - Shaul Mukamel
- Department
of Chemistry and Department of Physics and Astronomy, University of California, Irvine, California 92697-2025, United States
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15
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Riedle E, Roos MK, Thallmair S, Sailer CF, Krebs N, Fingerhut BP, de Vivie-Riedle R. Ultrafast photochemistry with two product channels: Wavepacket motion through two distinct conical intersections. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.02.086] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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16
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Pijeau S, Foster D, Hohenstein EG. Excited-State Dynamics of a Benzotriazole Photostabilizer: 2-(2′-Hydroxy-5′-methylphenyl)benzotriazole. J Phys Chem A 2017; 121:6377-6387. [DOI: 10.1021/acs.jpca.7b04504] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
Affiliation(s)
- Shiela Pijeau
- Department
of Chemistry and Biochemistry, The City College of New York, New York, New York 10031, United States
| | - Donneille Foster
- Department
of Chemistry and Biochemistry, The City College of New York, New York, New York 10031, United States
| | - Edward G. Hohenstein
- Department
of Chemistry and Biochemistry, The City College of New York, New York, New York 10031, United States
- Ph.D.
Program in Chemistry, The Graduate Center of the City University of New York, New York, New York 10016, United States
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17
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Pijeau S, Foster D, Hohenstein EG. Excited-State Dynamics of 2-(2′-Hydroxyphenyl)benzothiazole: Ultrafast Proton Transfer and Internal Conversion. J Phys Chem A 2017; 121:4595-4605. [DOI: 10.1021/acs.jpca.7b01215] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Affiliation(s)
- Shiela Pijeau
- Department
of Chemistry and Biochemistry, The City College of New York, New York, New York 10031, United States
| | - Donneille Foster
- Department
of Chemistry and Biochemistry, The City College of New York, New York, New York 10031, United States
| | - Edward G. Hohenstein
- Department
of Chemistry and Biochemistry, The City College of New York, New York, New York 10031, United States
- Ph.D.
Program in Chemistry, The Graduate Center of the City University of New York, New York, New York 10016, United States
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18
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Kearns NM, Mehlenbacher RD, Jones AC, Zanni MT. Broadband 2D electronic spectrometer using white light and pulse shaping: noise and signal evaluation at 1 and 100 kHz. OPTICS EXPRESS 2017; 25:7869-7883. [PMID: 28380905 DOI: 10.1364/oe.25.007869] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
We have developed a broad bandwidth two-dimensional electronic spectrometer that operates shot-to-shot at repetition rates up to 100 kHz using an acousto-optic pulse shaper. It is called a two-dimensional white-light (2D-WL) spectrometer because the input is white-light supercontinuum. Methods for 100 kHz data collection are studied to understand how laser noise is incorporated into 2D spectra during measurement. At 100 kHz, shot-to-shot scanning of the delays and phases of the pulses in the pulse sequence produces a 2D spectrum 13-times faster and with the same signal-to-noise as using mechanical stages and a chopper. Comparing 100 to 1 kHz repetition rates, data acquisition time is decreased by a factor of 200, which is beyond the improvement expected by the repetition rates alone due to reduction in 1/f noise. These improvements arise because shot-to-shot readout and modulation of the pulse train at 100 kHz enables the electronic coherences to be measured faster than the decay in correlation between laser intensities. Using white light supercontinuum for the pump and probe pulses produces high signal-to-noise spectra on samples with optical densities <0.1 within a few minutes of averaging and an instrument response time of <46 fs thereby demonstrating that that simple broadband continuum sources, although weak, are sufficient to create high quality 2D spectra with >200 nm bandwidth.
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19
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Carpenter BK, Harvey JN, Orr-Ewing AJ. The Study of Reactive Intermediates in Condensed Phases. J Am Chem Soc 2016; 138:4695-705. [DOI: 10.1021/jacs.6b01761] [Citation(s) in RCA: 74] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Barry K. Carpenter
- School
of Chemistry, Cardiff University, Park Place, Cardiff CF10 3AT, U.K
| | - Jeremy N. Harvey
- Department
of Chemistry, KU Leuven, Celestijnen Laan 200F, B-3001 Heverlee, Belgium
| | - Andrew J. Orr-Ewing
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.K
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20
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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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21
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Affiliation(s)
- Andrew J. Orr-Ewing
- School of Chemistry, University of Bristol, Bristol BS8 1TS, United Kingdom;
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22
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Harris SJ, Murdock D, Grubb MP, Clark IP, Greetham GM, Towrie M, Ashfold MNR. Tracking a Paternò–Büchi Reaction in Real Time Using Transient Electronic and Vibrational Spectroscopies. J Phys Chem A 2014; 118:10240-5. [DOI: 10.1021/jp507958y] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Stephanie J. Harris
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Daniel Murdock
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Michael P. Grubb
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
| | - Ian P. Clark
- Central
Laser Facility, Research Complex at Harwell, Science and Technology
Facilities Council, Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, United Kingdom
| | - Gregory M. Greetham
- Central
Laser Facility, Research Complex at Harwell, Science and Technology
Facilities Council, Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, United Kingdom
| | - Michael Towrie
- Central
Laser Facility, Research Complex at Harwell, Science and Technology
Facilities Council, Rutherford Appleton Laboratory, Didcot, Oxfordshire, OX11 0QX, United Kingdom
| | - Michael N. R. Ashfold
- School
of Chemistry, University of Bristol, Cantock’s Close, Bristol, BS8 1TS, United Kingdom
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23
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Verma PK, Koch F, Steinbacher A, Nuernberger P, Brixner T. Ultrafast UV-Induced Photoisomerization of Intramolecularly H-Bonded Symmetric β-Diketones. J Am Chem Soc 2014; 136:14981-9. [DOI: 10.1021/ja508059p] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Affiliation(s)
- Pramod Kumar Verma
- Institut für Physikalische
und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Federico Koch
- Institut für Physikalische
und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Andreas Steinbacher
- Institut für Physikalische
und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Patrick Nuernberger
- Institut für Physikalische
und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Tobias Brixner
- Institut für Physikalische
und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
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24
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Laptenok SP, Addison K, Heisler IA, Meech SR. Excited state structural dynamics in higher lying electronic states: S2 state of malachite green. Chem Phys Lett 2014. [DOI: 10.1016/j.cplett.2014.05.050] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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25
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Schalk O, Schuurman MS, Wu G, Lang P, Mucke M, Feifel R, Stolow A. Internal Conversion versus Intersystem Crossing: What Drives the Gas Phase Dynamics of Cyclic α,β-Enones? J Phys Chem A 2014; 118:2279-87. [DOI: 10.1021/jp4124937] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Oliver Schalk
- Department
of Physics, AlbaNova University Center, Stockholm University, Roslagstullsbacken 21, 109 61 Stockholm, Sweden
- Lehrstuhl für
BioMolekulare Optik, Ludwig-Maximilians-Universität, Oettingenstraße 67, 80538 München, Germany
- National Research Council of Canada, 100 Sussex Drive, Ottawa K1A 0R6, Canada
| | | | - Guorong Wu
- National Research Council of Canada, 100 Sussex Drive, Ottawa K1A 0R6, Canada
- State
Key Laboratory of Molecular Reaction Dynamics, Dalian
Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, P. R. China
- Synergetic Innovation Center of Quantum Information & Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026, P. R. China
| | - Peter Lang
- Lehrstuhl für
BioMolekulare Optik, Ludwig-Maximilians-Universität, Oettingenstraße 67, 80538 München, Germany
| | - Melanie Mucke
- Department
of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden
| | - Raimund Feifel
- Department
of Physics and Astronomy, Uppsala University, Box 516, 751 20 Uppsala, Sweden
| | - Albert Stolow
- National Research Council of Canada, 100 Sussex Drive, Ottawa K1A 0R6, Canada
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26
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Lee SN, Park J, Lim M, Joo T. Identification of an emitting molecular species by time-resolved fluorescence applied to the excited state dynamics of pigment yellow 101. Phys Chem Chem Phys 2014; 16:9394-402. [DOI: 10.1039/c3cp54546f] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Time-resolved fluorescence (TRF) with a resolution higher than the periods of vibrations may provide the vibrational spectrum of an emitting species by directly recording the vibrational wave packet motions in time.
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Affiliation(s)
- Seung Noh Lee
- Department of Chemistry
- Pohang University of Science and Technology (POSTECH)
- Pohang, South Korea
| | - Jaeheung Park
- Department of Chemistry and Chemistry Institute for Functional Materials
- Busan National University
- Busan, South Korea
| | - Manho Lim
- Department of Chemistry and Chemistry Institute for Functional Materials
- Busan National University
- Busan, South Korea
| | - Taiha Joo
- Department of Chemistry
- Pohang University of Science and Technology (POSTECH)
- Pohang, South Korea
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27
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Harris SJ, Murdock D, Grubb MP, Greetham GM, Clark IP, Towrie M, Ashfold MNR. Transient electronic and vibrational absorption studies of the photo-Claisen and photo-Fries rearrangements. Chem Sci 2014. [DOI: 10.1039/c3sc52893f] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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28
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Arruda BC, Sension RJ. Ultrafast polyene dynamics: the ring opening of 1,3-cyclohexadiene derivatives. Phys Chem Chem Phys 2014; 16:4439-55. [DOI: 10.1039/c3cp54767a] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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29
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Ashfold MNR. Photoinitiated quantum molecular dynamics: Concluding Remarks. Faraday Discuss 2013; 163:545-51. [DOI: 10.1039/c3fd00090g] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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30
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Stolow A. The three pillars of photo-initiated quantum molecular dynamics. Faraday Discuss 2013; 163:9-32; discussion 117-38. [DOI: 10.1039/c3fd90021e] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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