1
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Mi XP, Lu H, Xu T, Früchtl H, van Mourik T, Paterson MJ, Kirk SR, Jenkins S. Response of the mechanical and chiral character of ethane to ultra-fast laser pulses. J Comput Chem 2023. [PMID: 37698200 DOI: 10.1002/jcc.27225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/25/2023] [Accepted: 08/27/2023] [Indexed: 09/13/2023]
Abstract
A pair of simulated left and right circularly polarized ultra-fast laser pulses of duration 20 femtoseconds that induce a mixture of excited states are applied to ethane. The response of the electron dynamics is investigated within the next generation quantum theory of atoms in molecules (NG-QTAIM) using third-generation eigenvector-trajectories which are introduced in this work. This enables an analysis of the mechanical and chiral properties of the electron dynamics of ethane without needing to subject the C-C bond to external torsions as was the case for second-generation eigenvector-trajectories. The mechanical properties, in particular, the bond-flexing and bond-torsion were found to increase depending on the plane of the applied laser pulses. The bond-flexing and bond-torsion, depending on the plane of polarization, increases or decreases after the laser pulses are switched off. This is explainable in terms of directionally-dependent effects of the long-lasting superpositions of excited states. The chiral properties correspond to the ethane molecule being classified as formally achiral consistent with previous NG-QTAIM investigations. Future planned investigations using ultra-fast circularly polarized lasers are briefly discussed.
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Affiliation(s)
- Xiao Peng Mi
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, China
| | - Hui Lu
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, China
| | - Tianlv Xu
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, China
| | - Herbert Früchtl
- EaStCHEM School of Chemistry, University of Saint Andrews, Fife, UK
| | - Tanja van Mourik
- EaStCHEM School of Chemistry, University of Saint Andrews, Fife, UK
| | - Martin J Paterson
- Institute of Chemical Sciences, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh, UK
| | - Steven R Kirk
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, China
| | - Samantha Jenkins
- Key Laboratory of Chemical Biology and Traditional Chinese Medicine Research and Key Laboratory of Resource National and Local Joint Engineering Laboratory for New Petro-chemical Materials and Fine Utilization of Resources, College of Chemistry and Chemical Engineering, Hunan Normal University, Changsha, China
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2
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Vanzan M, Gil G, Castaldo D, Nordlander P, Corni S. Energy Transfer to Molecular Adsorbates by Transient Hot Electron Spillover. Nano Lett 2023; 23:2719-2725. [PMID: 37010208 PMCID: PMC10103299 DOI: 10.1021/acs.nanolett.3c00013] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/02/2023] [Revised: 03/21/2023] [Indexed: 06/19/2023]
Abstract
Hot electron (HE) photocatalysis is one of the most intriguing fields of nanoscience, with a clear potential for technological impact. Despite much effort, the mechanisms of HE photocatalysis are not fully understood. Here we investigate a mechanism based on transient electron spillover on a molecule and subsequent energy release into vibrational modes. We use state-of-the-art real-time Time Dependent Density Functional Theory (rt-TDDFT), simulating the dynamics of a HE moving within linear chains of Ag or Au atoms, on which CO, N2, or H2O are adsorbed. We estimate the energy a HE can release into adsorbate vibrational modes and show that certain modes are selectively activated. The energy transfer strongly depends on the adsorbate, the metal, and the HE energy. Considering a cumulative effect from multiple HEs, we estimate this mechanism can transfer tenths of an eV to molecular vibrations and could play an important role in HE photocatalysis.
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Affiliation(s)
- Mirko Vanzan
- Department
of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
- Department
of Physics, University of Milan, Via Celoria 16, 20133 Milan, Italy
| | - Gabriel Gil
- Instituto
de Cibernetica, Matematica y Física, Calle E esq 15 Vedado, 10400 La Habana, Cuba
| | - Davide Castaldo
- Department
of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Peter Nordlander
- Department
of Physics and Astronomy, Rice University, Houston, Texas 77005, United States
| | - Stefano Corni
- Department
of Chemical Sciences, University of Padova, Via Marzolo 1, 35131 Padova, Italy
- CNR
Institute of Nanoscience, via Campi 213/A, 41125 Modena, Italy
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3
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Hanasaki K, Ali ZA, Choi M, Del Ben M, Wong BM. Implementation of real-time TDDFT for periodic systems in the open-source PySCF software package. J Comput Chem 2023; 44:980-987. [PMID: 36564979 DOI: 10.1002/jcc.27058] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 11/30/2022] [Accepted: 12/06/2022] [Indexed: 12/25/2022]
Abstract
We present a new implementation of real-time time-dependent density functional theory (RT-TDDFT) for calculating excited-state dynamics of periodic systems in the open-source Python-based PySCF software package. Our implementation uses Gaussian basis functions in a velocity gauge formalism and can be applied to periodic surfaces, condensed-phase, and molecular systems. As representative benchmark applications, we present optical absorption calculations of various molecular and bulk systems and a real-time simulation of field-induced dynamics of a (ZnO)4 molecular cluster on a periodic graphene sheet. We present representative calculations on optical response of solids to infinitesimal external fields as well as real-time charge-transfer dynamics induced by strong pulsed laser fields. Due to the widespread use of the Python language, our RT-TDDFT implementation can be easily modified and provides a new capability in the PySCF code for real-time excited-state calculations of chemical and material systems.
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Affiliation(s)
- Kota Hanasaki
- Department of Chemical & Environmental Engineering, Materials Science & Engineering Program, Department of Chemistry, and Department of Physics & Astronomy, University of California-Riverside, Riverside, California, USA
| | - Zulfikhar A Ali
- Department of Chemical & Environmental Engineering, Materials Science & Engineering Program, Department of Chemistry, and Department of Physics & Astronomy, University of California-Riverside, Riverside, California, USA
| | - Min Choi
- Department of Chemical & Environmental Engineering, Materials Science & Engineering Program, Department of Chemistry, and Department of Physics & Astronomy, University of California-Riverside, Riverside, California, USA
| | - Mauro Del Ben
- Applied Mathematics & Computational Research Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Bryan M Wong
- Department of Chemical & Environmental Engineering, Materials Science & Engineering Program, Department of Chemistry, and Department of Physics & Astronomy, University of California-Riverside, Riverside, California, USA
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4
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Tremblay JC, Blanc A, Krause P, Giri S, Dixit G. Probing Electronic Symmetry Reduction during Charge Migration via Time-Resolved X-Ray Diffraction. Chemphyschem 2023; 24:e202200463. [PMID: 36166371 DOI: 10.1002/cphc.202200463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2022] [Revised: 09/19/2022] [Indexed: 01/19/2023]
Abstract
The present work focuses on probing ultrafast charge migration after symmetry-breaking excitation using ultrashort laser pulses. LiCN is chosen as prototypical system because it can be oriented in the laboratory frame and it possesses optically-accessible charge transfer states at low energies. The charge migration is simulated within the hybrid time-dependent density functional theory/configuration interaction framework. Time-resolved electronic current densities and simulated time-resolved x-ray diffraction signals are used to unravel the mechanism of charge migration. Our simulations demonstrate that specific choices of laser polarization lead to a control over the symmetry of the induced charge migration. Moreover, time-resolved x-ray diffraction signals are shown to encode transient symmetry reduction at intermediate times.
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Affiliation(s)
| | - Ambre Blanc
- CNRS-Université de Lorraine, LPCT, 57070, Metz, France
| | - Pascal Krause
- Theory of Electron Dynamics and Spectroscopy, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Hahn-Meitner Platz 1, 14109, Berlin, Germany
| | - Sucharita Giri
- Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
| | - Gopal Dixit
- Department of Physics, Indian Institute of Technology Bombay, Powai, Mumbai, 400076, India
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5
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Takatsuka K. Quantum Chaos in the Dynamics of Molecules. Entropy (Basel) 2022; 25:63. [PMID: 36673204 PMCID: PMC9857761 DOI: 10.3390/e25010063] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/07/2022] [Revised: 12/22/2022] [Accepted: 12/22/2022] [Indexed: 06/17/2023]
Abstract
Quantum chaos is reviewed from the viewpoint of "what is molecule?", particularly placing emphasis on their dynamics. Molecules are composed of heavy nuclei and light electrons, and thereby the very basic molecular theory due to Born and Oppenheimer gives a view that quantum electronic states provide potential functions working on nuclei, which in turn are often treated classically or semiclassically. Therefore, the classic study of chaos in molecular science began with those nuclear dynamics particularly about the vibrational energy randomization within a molecule. Statistical laws in probabilities and rates of chemical reactions even for small molecules of several atoms are among the chemical phenomena requiring the notion of chaos. Particularly the dynamics behind unimolecular decomposition are referred to as Intra-molecular Vibrational energy Redistribution (IVR). Semiclassical mechanics is also one of the main research fields of quantum chaos. We herein demonstrate chaos that appears only in semiclassical and full quantum dynamics. A fundamental phenomenon possibly giving birth to quantum chaos is "bifurcation and merging" of quantum wavepackets, rather than "stretching and folding" of the baker's transformation and the horseshoe map as a geometrical foundation of classical chaos. Such wavepacket bifurcation and merging are indeed experimentally measurable as we showed before in the series of studies on real-time probing of nonadiabatic chemical reactions. After tracking these aspects of molecular chaos, we will explore quantum chaos found in nonadiabatic electron wavepacket dynamics, which emerges in the realm far beyond the Born-Oppenheimer paradigm. In this class of chaos, we propose a notion of Intra-molecular Nonadiabatic Electronic Energy Redistribution (INEER), which is a consequence of the chaotic fluxes of electrons and energy within a molecule.
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Affiliation(s)
- Kazuo Takatsuka
- Fukui Institute for Fundamental Chemistry, Kyoto University, Kyoto 606-8103, Japan
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6
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Schäfer JL, Langkabel F, Bande A. Three- Electron Dynamics of the Interparticle Coulombic Decay in Doubly Excited Clusters with One-Dimensional Continuum Confinement. Molecules 2022; 27. [PMID: 36557847 DOI: 10.3390/molecules27248713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 10/27/2022] [Revised: 12/02/2022] [Accepted: 12/05/2022] [Indexed: 12/13/2022]
Abstract
A detailed analysis of the electronic structure and decay dynamics in a symmetric system with three electrons in three linearly aligned binding sites representing quantum dots (QDs) is given. The two outer A QDs are two-level potentials and can act as (virtual) photon emitters, whereas the central B QD can be ionized from its one level into a continuum confined on the QD axis upon absorbing virtual photons in the inter-Coulombic decay (ICD) process. Two scenarios in such an ABA array are explored. One ICD process is from a singly excited resonance state, whose decay releasing one virtual photon we find superimposed with resonance energy transfer among both A QDs. Moreover, the decay-process manifold for a doubly excited (DE) resonance is explored, in which collective ICD among all three sites and excited ICD among the outer QDs engage. Rates for all processes are found to be extremely low, although ICD rates with two neighbors are predicted to double compared to ICD among two sites only. The slowing is caused by Coulomb barriers imposed from ground or excited state electrons in the A sites. Outliers occur on the one hand at short distances, where the charge transfer among QDs mixes the possible decay pathways. On the other hand, we discovered a shape resonance-enhanced DE-ICD pathway, in which an excited and localized B* shape resonance state forms, which is able to decay quickly into the final ICD continuum.
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7
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Steves MA, Rajabpour S, Wang K, Dong C, He W, Quek SY, Robinson JA, Knappenberger KL. Atomic-Level Structure Determines Electron-Phonon Scattering Rates in 2-D Polar Metal Heterostructures. ACS Nano 2021; 15:17780-17789. [PMID: 34665593 DOI: 10.1021/acsnano.1c05944] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
The electron dynamics of atomically thin 2-D polar metal heterostructures, which consisted of a few crystalline metal atomic layers intercalated between hexagonal silicon carbide and graphene grown from the silicon carbide, were studied using nearly degenerate transient absorption spectroscopy. Optical pumping created charge carriers in both the 2-D metals and graphene components. Wavelength-dependent probing suggests that graphene-to-metal carrier transfer occurred on a sub-picosecond time scale. Following rapid (<300 fs) carrier-carrier scattering, charge carriers monitored through the metal interband transition relaxed through several consecutive cooling mechanisms that included sub-picosecond carrier-phonon scattering and dissipation to the silicon carbide substrate over tens of picoseconds. By studying 2-D In, 2-D Ga, and a Ga/In alloy, we resolved accelerated electron-phonon scattering rates upon alloy formation as well as structural influences on the excitation of in-plane phonon shear modes. More rapid cooling in alloys is attributed to increased lattice disorder, which was observed through correlative polarization-resolved second harmonic generation and electron microscopy. This connection between the electronic relaxation rates, far-field optical responses, and metal lattice disorder is made possible by the intimate relation between nonlinear optical properties and atomic-level structure in these materials. These studies provided insights into electronic carrier dynamics in 2-D crystalline elemental metals, including resolving contributions from specific components of a 2-D metal-containing heterojunction. The correlative ultrafast spectroscopy and nonlinear microscopy results suggest that the energy dissipation rates can be tuned through atomic-level structures.
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Affiliation(s)
- Megan A Steves
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Siavash Rajabpour
- Department of Chemical Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ke Wang
- Materials Characterization Laboratory, Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Chengye Dong
- 2D Crystal Consortium, Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Wen He
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive, Singapore 117456, Singapore
- Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore 117456, Singapore
| | - Su Ying Quek
- Department of Materials Science and Engineering, National University of Singapore, 9 Engineering Drive, Singapore 117456, Singapore
- Centre for Advanced 2D Materials, National University of Singapore, 6 Science Drive 2, Singapore 117456, Singapore
- Department of Physics, National University of Singapore, Singapore 117456, Singapore
- NUS Graduate School Integrative Sciences and Engineering Programme, National University of Singapore, Singapore 117456, Singapore
| | - Joshua A Robinson
- 2D Crystal Consortium, Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Center for 2D and Layered Materials, Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Materials Science and Engineering, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Kenneth L Knappenberger
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
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8
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Fagan AM, Jeffries WR, Knappenberger KL, Schaak RE. Synthetic Control of Hot-Electron Thermalization Efficiency in Size-Tunable Au-Pt Hybrid Nanoparticles. ACS Nano 2021; 15:1378-1387. [PMID: 33337141 DOI: 10.1021/acsnano.0c08661] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Gold nanoparticles are well-known to exhibit size-dependent properties that are responsible for their unique catalytic, optical, and electronic applications. However, electron-phonon coupling, which is important for photocatalysis and light harvesting, is one of the rare properties of gold that is size-independent above a threshold value, e.g., for nanospheres larger than approximately 5 nm in diameter. Here, we show that when interfaced to a comparably sized Pt nanoparticle, the electron-phonon coupling constant of the hybrid material depends on the diameter of the Au domain. This is important because the electron-phonon coupling constant describes the efficiency by which hot electrons are converted to local heat by the primary electron-phonon scattering thermalization channel. We begin by synthesizing a library of Au-Pt hybrid nanoparticle heterodimers by growing size-tunable Au nanoparticles on Pt nanoparticle seeds. By systematically varying reagent concentration and reaction time, the Au domain diameter of the Au-Pt hybrid nanoparticle heterodimers can be tuned between 4.4 and 16 nm while the size of the Pt domain remains constant. Calibration curves allow us to dial in precise Au domain sizes, and microscopic analysis of the Au-Pt heterodimers provides insights into how they grow and how their morphologies evolve. Femtosecond time-resolved transient absorption spectroscopy reveals that for Au-Pt heterodimers having Au domain diameters of 8.7 to 14 nm, the electron-phonon coupling constant decreases by more than 80%, which is not observed for comparably sized Au nanoparticles. Interfacing smaller Au domains with Pt nanoparticle surfaces causes an increase in the density of states near the Fermi level of Au, which results in accelerated thermalization times through an increased number of electron-phonon interactions. The combination of precision hybrid nanoparticle synthesis and size-dependent electron-phonon coupling may be important for designing composite metals for photocatalytic and light-harvesting applications and for engineering different functions into established materials.
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9
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Müller C, Sharma M, Sierka M. Real-time time-dependent density functional theory using density fitting and the continuous fast multipole method. J Comput Chem 2020; 41:2573-2582. [PMID: 33464600 DOI: 10.1002/jcc.26412] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Revised: 08/17/2020] [Accepted: 08/18/2020] [Indexed: 11/07/2022]
Abstract
An implementation of real-time time-dependent density functional theory (RT-TDDFT) within the TURBOMOLE program package is reported using Gaussian-type orbitals as basis functions, second and fourth order Magnus propagator, and the self-consistent field as well as the predictor-corrector time integration schemes. The Coulomb contribution to the Kohn-Sham matrix is calculated combining density fitting approximation and the continuous fast multipole method. Performance of the implementation is benchmarked for molecular systems with different sizes and dimensionalities. For linear alkane chains, the wall time for density matrix time propagation step is comparable to the Kohn-Sham (KS) matrix construction. However, for larger two- and three-dimensional molecules, with up to about 5,000 basis functions, the computational effort of RT-TDDFT calculations is dominated by the KS matrix evaluation. In addition, the maximum time step is evaluated using a set of small molecules of different polarities. The photoabsorption spectra of several molecular systems calculated using RT-TDDFT are compared to those obtained using linear response time-dependent density functional theory and coupled cluster methods.
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Affiliation(s)
- Carolin Müller
- Otto Schott Institute of Materials Research, Friedrich Schiller University of Jena, Jena, Germany
| | - Manas Sharma
- Otto Schott Institute of Materials Research, Friedrich Schiller University of Jena, Jena, Germany
| | - Marek Sierka
- Otto Schott Institute of Materials Research, Friedrich Schiller University of Jena, Jena, Germany
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10
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Jeffries WR, Park K, Vaia RA, Knappenberger KL. Resolving Electron-Electron Scattering in Plasmonic Nanorod Ensembles Using Two-Dimensional Electronic Spectroscopy. Nano Lett 2020; 20:7722-7727. [PMID: 32931697 DOI: 10.1021/acs.nanolett.0c03272] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
The use of two-dimensional electronic spectroscopy (2DES) to study electron-electron scattering dynamics in plasmonic gold nanorods is described. The 2DES resolved the time-dependent plasmon homogeneous line width Γh(t), which was sensitive to changes in Fermi-level carrier densities. This approach was effective because electronic excitation accelerated plasmon dephasing, which broadened Γh. Analysis of Γh(t) indicated plasmon coherence times were decreased by 20-50%, depending on excitation conditions. Electron-electron scattering rates of approximately 0.01 fs-1 were obtained by fitting the time-dependent Γh broadening; rates increased quadratically with both excitation pulse energy and frequency. This rate dependence agreed with Fermi-liquid theory-based predictions. Hot electron thermalization through electron-phonon scattering resulted in Γh narrowing. To our knowledge, this is the first use of the plasmon Γh(t) to isolate electron-electron scattering dynamics in colloidal metal nanoparticles. These results illustrate the effectiveness of 2DES for studying hot electron dynamics of solution-phase plasmonic ensembles.
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Affiliation(s)
- William R Jeffries
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Kyoungweon Park
- Air Force Research Laboratory, 2941 Hobson Way, Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Richard A Vaia
- Air Force Research Laboratory, 2941 Hobson Way, Wright-Patterson Air Force Base, Ohio 45433, United States
| | - Kenneth L Knappenberger
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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11
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Zhou M, Zeng C, Li Q, Higaki T, Jin R. Gold Nanoclusters: Bridging Gold Complexes and Plasmonic Nanoparticles in Photophysical Properties. Nanomaterials (Basel) 2019; 9:E933. [PMID: 31261666 DOI: 10.3390/nano9070933] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 06/21/2019] [Accepted: 06/25/2019] [Indexed: 01/10/2023]
Abstract
Recent advances in the determination of crystal structures and studies of optical properties of gold nanoclusters in the size range from tens to hundreds of gold atoms have started to reveal the grand evolution from gold complexes to nanoclusters and further to plasmonic nanoparticles. However, a detailed comparison of their photophysical properties is still lacking. Here, we compared the excited state behaviors of gold complexes, nanolcusters, and plasmonic nanoparticles, as well as small organic molecules by choosing four typical examples including the Au10 complex, Au25 nanocluster (1 nm metal core), 13 diameter Au nanoparticles, and Rhodamine B. To compare their photophysical behaviors, we performed steady-state absorption, photoluminescence, and femtosecond transient absorption spectroscopic measurements. It was found that gold nanoclusters behave somewhat like small molecules, showing both rapid internal conversion (<1 ps) and long-lived excited state lifetime (about 100 ns). Unlike the nanocluster form in which metal–metal transitions dominate, gold complexes showed significant charge transfer between metal atoms and surface ligands. Plasmonic gold nanoparticles, on the other hand, had electrons being heated and cooled (~100 ps time scale) after photo-excitation, and the relaxation was dominated by electron–electron scattering, electron–phonon coupling, and energy dissipation. In both nanoclusters and plasmonic nanoparticles, one can observe coherent oscillations of the metal core, but with different fundamental origins. Overall, this work provides some benchmarking features for organic dye molecules, organometallic complexes, metal nanoclusters, and plasmonic nanoparticles.
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12
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Coffee RN, Cryan JP, Duris J, Helml W, Li S, Marinelli A. Development of ultrafast capabilities for X-ray free-electron lasers at the linac coherent light source. Philos Trans A Math Phys Eng Sci 2019; 377:20180386. [PMID: 30929632 PMCID: PMC6452055 DOI: 10.1098/rsta.2018.0386] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/18/2019] [Indexed: 05/07/2023]
Abstract
The ability to produce ultrashort, high-brightness X-ray pulses is revolutionizing the field of ultrafast X-ray spectroscopy. Free-electron laser (FEL) facilities are driving this revolution, but unique aspects of the FEL process make the required characterization and use of the pulses challenging. In this paper, we describe a number of developments in the generation of ultrashort X-ray FEL pulses, and the concomitant progress in the experimental capabilities necessary for their characterization and use at the Linac Coherent Light Source. This includes the development of sub-femtosecond hard and soft X-ray pulses, along with ultrafast characterization techniques for these pulses. We also describe improved techniques for optical cross-correlation as needed to address the persistent challenge of external optical laser synchronization with these ultrashort X-ray pulses. This article is part of the theme issue 'Measurement of ultrafast electronic and structural dynamics with X-rays'.
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Affiliation(s)
- Ryan N. Coffee
- SLAC National Accelerator Laboratory, Linac Coherent Light Source, Menlo Park, CA 94025, USA
- SLAC National Accelerator Laboratory, Stanford Pulse Institute, Menlo Park, CA 94025, USA
| | - James P. Cryan
- SLAC National Accelerator Laboratory, Linac Coherent Light Source, Menlo Park, CA 94025, USA
- SLAC National Accelerator Laboratory, Stanford Pulse Institute, Menlo Park, CA 94025, USA
| | - Joseph Duris
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Wolfram Helml
- Zentrum für Synchrotronstrahlung, Technische Universität Dortmund, Maria-Goeppert-Mayer-Straße 2, 44227 Dortmund, Germany
- Physik-Department E11, Technische Universität München, James-Franck-Straße 1, 85748 Garching, Germany
| | - Siqi Li
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
- Department of Physics, Stanford University, Stanford, CA 94305, USA
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13
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Weber F, Aziz EF, Bande A. Interdependence of ICD rates in paired quantum dots on geometry. J Comput Chem 2017; 38:2141-2150. [PMID: 28568014 DOI: 10.1002/jcc.24843] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2017] [Revised: 04/13/2017] [Accepted: 04/26/2017] [Indexed: 11/09/2022]
Abstract
Using state-of-the-art antisymmetrized multiconfiguration time-dependent Hartree (MCTDH) electron dynamics calculations we study the interdependence of the intermolecular Coulombic decay (ICD) process on the geometric parameters of a doubly-charged paired quantum dot (PQD) model system in the framework of the effective mass approximation (EMA). We find that ICD displays a maximum rate for a certain geometry of the electron-emitting quantum dot, which is simultaneously dependent on both the distance between the quantum dots as well as the photon-absorbing quantum dot's geometry. The rate maximum is shown to be caused by the competing effects of polarization of electron density and Coulomb repulsion. The ICD rate-maximized PQD geometry in GaAs QDs yields a decay time of 102.39 ps. It is given by two vertically-aligned cylindrical QDs with radii of 14.42 nm separated by 86.62 nm. The photon absorbing QD then has a height of 46.59 nm and the electron emitting QD a height of 16.33 nm. © 2017 Wiley Periodicals, Inc.
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Affiliation(s)
- Fabian Weber
- Institute of Methods for Material Development, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, Berlin, 12489, Germany
| | - Emad F Aziz
- Institute of Methods for Material Development, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, Berlin, 12489, Germany.,Department of Physics, Freie Universitt Berlin, Arnimallee 14, Berlin, 14195, Germany.,School of Chemistry, Monash University, Clayton, Victoria, 3800, Australia
| | - Annika Bande
- Institute of Methods for Material Development, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Albert-Einstein-Str. 15, Berlin, 12489, Germany
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14
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Zhou M, Jin R, Sfeir MY, Chen Y, Song Y, Jin R. Electron localization in rod-shaped triicosahedral gold nanocluster. Proc Natl Acad Sci U S A 2017; 114:E4697-705. [PMID: 28559316 DOI: 10.1073/pnas.1704699114] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Atomically precise gold nanocluster based on linear assembly of repeating icosahedrons (clusters of clusters) is a unique type of linear nanostructure, which exhibits strong near-infrared absorption as their free electrons are confined in a one-dimensional quantum box. Little is known about the carrier dynamics in these nanoclusters, which limit their energy-related applications. Here, we reported the observation of exciton localization in triicosahedral Au37 nanoclusters (0.5 nm in diameter and 1.6 nm in length) by measuring femtosecond and nanosecond carrier dynamics. Upon photoexcitation to S1 electronic state, electrons in Au37 undergo ∼100-ps localization from the two vertexes of three icosahedrons to one vertex, forming a long-lived S1* state. Such phenomenon is not observed in Au25 (dimer) and Au13 (monomer) consisting of two and one icosahedrons, respectively. We have further observed temperature dependence on the localization process, which proves it is thermally driven. Two excited-state vibration modes with frequencies of 20 and 70 cm-1 observed in the kinetic traces are assigned to the axial and radial breathing modes, respectively. The electron localization is ascribed to the structural distortion of Au37 in the excited state induced by the strong coherent vibrations. The observed electron localization phenomenon provides unique physical insight into one-dimensional gold nanoclusters and other nanostructures, which will advance their applications in solar-energy storage and conversion.
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15
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Shibuta M, Hirata N, Eguchi T, Nakajima A. Photoexcited State Confinement in Two-Dimensional Crystalline Anthracene Monolayer at Room Temperature. ACS Nano 2017; 11:4307-4314. [PMID: 28399361 DOI: 10.1021/acsnano.7b01506] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Organic thin film electronics place a high demand on bottom-up technology to form a two-dimensionally (2D) functional unit consisting of a single molecular crystalline layer bound to a layered structure. As the strong interaction between a substrate and molecules makes it difficult to evaluate the electronic properties of organic films, the nature of electronic excited states has not been elucidated. Here, we study a 2D crystalline anthracene monolayer electronically decoupled by alkanethiolates on a gold substrate using scanning tunneling microscopy and time-resolved two-photon photoemission spectroscopy and unravel the geometric/electronic structures and excited electron dynamics. Our data reveal that dispersive 2D excited electrons on the surface can be highly coupled with an annihilation of nondispersive excitons that facilitate electron emission with vibronic interaction. Our results provide a fundamental framework for understanding photoexcited anthracene monolayer and show how the coupling between dispersive and nondispersive excited states may assist charge separation in crystalline molecular layers.
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Affiliation(s)
- Masahiro Shibuta
- Keio Institute of Pure and Applied Science (KiPAS), Keio University , 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Naoyuki Hirata
- Nakajima Designer Nanocluster Assembly Project, ERATO, Japan Science and Technology Agency (JST) , 3-2-1 Sakado, Takatsu-ku, Kawasaki 213-0012, Japan
- Department of Chemistry, Faculty of Science and Technology, Keio University , 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Toyoaki Eguchi
- Nakajima Designer Nanocluster Assembly Project, ERATO, Japan Science and Technology Agency (JST) , 3-2-1 Sakado, Takatsu-ku, Kawasaki 213-0012, Japan
- Department of Chemistry, Faculty of Science and Technology, Keio University , 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Atsushi Nakajima
- Keio Institute of Pure and Applied Science (KiPAS), Keio University , 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
- Nakajima Designer Nanocluster Assembly Project, ERATO, Japan Science and Technology Agency (JST) , 3-2-1 Sakado, Takatsu-ku, Kawasaki 213-0012, Japan
- Department of Chemistry, Faculty of Science and Technology, Keio University , 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
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16
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Abstract
The photochemistry of TiO2 has been studied intensively since it was discovered that TiO2 can act as a photocatalyst. Nevertheless, it has proven difficult to establish the detailed charge-transfer processes involved, partly because the excited states involved are difficult to study. Here we present evidence of the existence of hydroxyl-induced excited states in the conduction band region. Using two-photon photoemission, we show that stepwise photoexcitation from filled band gap states lying 0.8 eV below the Fermi level of rutile TiO2(110) excites hydroxyl-induced states 2.73 eV above the Fermi level that has an onset energy of ∼3.1 eV. The onset is shifted to lower energy by the coadsorption of molecular water, which suggests a means of tuning the energy of the excited state.
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Affiliation(s)
- Yu Zhang
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
- London
Centre for Nanotechnology, University College
London, 17-19 Gordon
Street, London WC1H 0AH, United Kingdom
| | - Daniel T. Payne
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
- London
Centre for Nanotechnology, University College
London, 17-19 Gordon
Street, London WC1H 0AH, United Kingdom
| | - Chi L. Pang
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
- London
Centre for Nanotechnology, University College
London, 17-19 Gordon
Street, London WC1H 0AH, United Kingdom
| | - Helen
H. Fielding
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
| | - Geoff Thornton
- Department
of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, United Kingdom
- London
Centre for Nanotechnology, University College
London, 17-19 Gordon
Street, London WC1H 0AH, United Kingdom
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17
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Okino T, Furukawa Y, Nabekawa Y, Miyabe S, Amani Eilanlou A, Takahashi EJ, Yamanouchi K, Midorikawa K. Direct observation of an attosecond electron wave packet in a nitrogen molecule. Sci Adv 2015; 1:e1500356. [PMID: 26601262 PMCID: PMC4643781 DOI: 10.1126/sciadv.1500356] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/25/2015] [Accepted: 07/04/2015] [Indexed: 05/09/2023]
Abstract
Capturing electron motion in a molecule is the basis of understanding or steering chemical reactions. Nonlinear Fourier transform spectroscopy using an attosecond-pump/attosecond-probe technique is used to observe an attosecond electron wave packet in a nitrogen molecule in real time. The 500-as electronic motion between two bound electronic states in a nitrogen molecule is captured by measuring the fragment ions with the same kinetic energy generated in sequential two-photon dissociative ionization processes. The temporal evolution of electronic coherence originating from various electronic states is visualized via the fragment ions appearing after irradiation of the probe pulse. This observation of an attosecond molecular electron wave packet is a critical step in understanding coupled nuclear and electron motion in polyatomic and biological molecules to explore attochemistry.
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Affiliation(s)
- Tomoya Okino
- Attosecond Science Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Corresponding author. E-mail: (T.O.); (K.M.)
| | - Yusuke Furukawa
- Attosecond Science Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Yasuo Nabekawa
- Attosecond Science Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Shungo Miyabe
- Attosecond Science Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - A. Amani Eilanlou
- Attosecond Science Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Eiji J. Takahashi
- Attosecond Science Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
| | - Kaoru Yamanouchi
- Department of Chemistry, School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
| | - Katsumi Midorikawa
- Attosecond Science Research Team, RIKEN Center for Advanced Photonics, 2-1 Hirosawa, Wako-shi, Saitama 351-0198, Japan
- Corresponding author. E-mail: (T.O.); (K.M.)
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18
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Despré V, Marciniak A, Loriot V, Galbraith MCE, Rouzée A, Vrakking MJJ, Lépine F, Kuleff AI. Attosecond Hole Migration in Benzene Molecules Surviving Nuclear Motion. J Phys Chem Lett 2015; 6:426-31. [PMID: 26261959 DOI: 10.1021/jz502493j] [Citation(s) in RCA: 60] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Hole migration is a fascinating process driven by electron correlation, in which purely electronic dynamics occur on a very short time scale in complex ionized molecules, prior to the onset of nuclear motion. However, it is expected that due to coupling to the nuclear dynamics, these oscillations will be rapidly damped and smeared out, which makes experimental observation of the hole migration process rather difficult. In this Letter, we demonstrate that the instantaneous ionization of benzene molecules initiates an ultrafast hole migration characterized by a periodic breathing of the hole density between the carbon ring and surrounding hydrogen atoms on a subfemtosecond time scale. We show that these oscillations survive the dephasing introduced by the nuclear motion for a long enough time to allow their observation. We argue that this offers an ideal benchmark for studying the influence of hole migration on molecular reactivity.
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Affiliation(s)
- V Despré
- †Institut Lumière Matière, Université Lyon 1, CNRS, UMR 5306, 10 Rue Ada Byron, 69622 Villeurbanne Cedex, France
| | - A Marciniak
- †Institut Lumière Matière, Université Lyon 1, CNRS, UMR 5306, 10 Rue Ada Byron, 69622 Villeurbanne Cedex, France
| | - V Loriot
- †Institut Lumière Matière, Université Lyon 1, CNRS, UMR 5306, 10 Rue Ada Byron, 69622 Villeurbanne Cedex, France
| | - M C E Galbraith
- ‡Max-Born-Institut, Max Born Strasse 2A, D-12489 Berlin, Germany
| | - A Rouzée
- ‡Max-Born-Institut, Max Born Strasse 2A, D-12489 Berlin, Germany
| | - M J J Vrakking
- ‡Max-Born-Institut, Max Born Strasse 2A, D-12489 Berlin, Germany
| | - F Lépine
- †Institut Lumière Matière, Université Lyon 1, CNRS, UMR 5306, 10 Rue Ada Byron, 69622 Villeurbanne Cedex, France
| | - A I Kuleff
- §Theoretische Chemie, PCI, Universität Heidelberg, Im Neuenheimer Feld 229, 69120 Heidelberg, Germany
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19
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Ayzner AL, Nordlund D, Kim DH, Bao Z, Toney MF. Ultrafast Electron Transfer at Organic Semiconductor Interfaces: Importance of Molecular Orientation. J Phys Chem Lett 2015; 6:6-12. [PMID: 26263084 DOI: 10.1021/jz502253r] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Much is known about the rate of photoexcited charge generation in at organic donor/acceptor (D/A) heterojunctions overaged over all relative arrangements. However, there has been very little experimental work investigating how the photoexcited electron transfer (ET) rate depends on the precise relative molecular orientation between D and A in thin solid films. This is the question that we address in this work. We find that the ET rate depends strongly on the relative molecular arrangement: The interface where the model donor compound copper phthalocyanine is oriented face-on with respect to the fullerene C60 acceptor yields a rate that is approximately 4 times faster than that of the edge-on oriented interface. Our results suggest that the D/A electronic coupling is significantly enhanced in the face-on case, which agrees well with theoretical predictions, underscoring the importance of controlling the relative interfacial molecular orientation.
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Affiliation(s)
- Alexander L Ayzner
- †Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States
- ‡Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Dennis Nordlund
- ‡Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
| | - Do-Hwan Kim
- §Department of Organic Materials and Fiber Engineering, Soongsil University, Seoul, 156-743 Korea
| | - Zhenan Bao
- †Department of Chemical Engineering, Stanford University, Stanford, California 94305, United States
| | - Michael F Toney
- ‡Stanford Synchrotron Radiation Lightsource, SLAC National Accelerator Laboratory, Menlo Park, California 94025, United States
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20
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Abstract
Defects play a fundamental role in the energy relaxation of hot photoexcited carriers in graphene, thus a complete understanding of these processes are vital for improving the development of graphene devices. Recently, it has been theoretically predicted and experimentally demonstrated that defect-assisted acoustic phonon supercollision, the collision between a carrier and both an acoustic phonon and a defect, is an important energy relaxation process for carriers with excess energy below the optical phonon emission. Here, we studied samples with defects optically generated in a controlled manner to experimentally probe the supercollision model as a function of the defect density. We present pump and probe transient absorption measurements showing that the decay time decreases as the density of defect increases as predicted by the supercollision model.
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Affiliation(s)
- Thonimar V Alencar
- Department of Physics, Federal University of Minas Gerais , 30123-970 Belo Horizonte, MG, Brazil
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21
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Abstract
We report the excited-state electron dynamics for ultrathin films of NaCl on Ag(100). The first three image potential states (IPSs) were initially observed following excitation. The electrons in the spatially delocalized n = 1 IPS decayed on the ultrafast time scale into multiple spatially localized states lower in energy. The localized electronic states are proposed to correspond to electrons trapped at defects in the NaCl islands. Coverage and temperature dependence of the localized states support the assignment to surface trap states existing at the NaCl/vacuum interface. These results highlight the importance of electron trapping in ultrathin insulating layers.
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Affiliation(s)
- David E Suich
- Department of Chemistry, University of California at Berkeley, 419 Latimer Hall, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, United States
| | - Benjamin W Caplins
- Department of Chemistry, University of California at Berkeley, 419 Latimer Hall, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, United States
| | - Alex J Shearer
- Department of Chemistry, University of California at Berkeley, 419 Latimer Hall, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, United States
| | - Charles B Harris
- Department of Chemistry, University of California at Berkeley, 419 Latimer Hall, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, United States
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22
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Abstract
A phthalocyanine/Ag(111) interface state is observed for the first time using time- and angle-resolved two-photon photoemission. For monolayer films of metal-free (H2Pc) and iron phthalocyanine (FePc) on Ag(111), the state exists 0.23 ± 0.03 and 0.31 ± 0.03 eV above the Fermi level, respectively. Angle-resolved spectra show the state to be highly dispersive with an effective mass of 0.50 ± 0.15 me for H2Pc and 0.67 ± 0.14 me for FePc. Density functional theory calculations on the H2Pc/Ag(111) surface allow us to characterize this state as being a hybrid state resulting from the interaction between the unoccupied molecular states of the phthalocyanine ligand and the Shockley surface state present on the bare Ag(111) surface. This work, when taken together with the extensive literature on the 3,4,9,10-perylene tetracarboxylic dianhydride/Ag interface state, provides compelling evidence that the hybridization of metal surface states with molecular electronic states is a general phenomenon.
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Affiliation(s)
- Benjamin W Caplins
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - David E Suich
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Alex J Shearer
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Charles B Harris
- Department of Chemistry, University of California at Berkeley, Berkeley, California 94720, United States
- Chemical Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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23
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Ranitovic P, Hogle CW, Rivière P, Palacios A, Tong XM, Toshima N, González-Castrillo A, Martin L, Martín F, Murnane MM, Kapteyn H. Attosecond vacuum UV coherent control of molecular dynamics. Proc Natl Acad Sci U S A 2014; 111:912-7. [PMID: 24395768 DOI: 10.1073/pnas.1321999111] [Citation(s) in RCA: 96] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
High harmonic light sources make it possible to access attosecond timescales, thus opening up the prospect of manipulating electronic wave packets for steering molecular dynamics. However, two decades after the birth of attosecond physics, the concept of attosecond chemistry has not yet been realized; this is because excitation and manipulation of molecular orbitals requires precisely controlled attosecond waveforms in the deep UV, which have not yet been synthesized. Here, we present a unique approach using attosecond vacuum UV pulse-trains to coherently excite and control the outcome of a simple chemical reaction in a deuterium molecule in a non-Born-Oppenheimer regime. By controlling the interfering pathways of electron wave packets in the excited neutral and singly ionized molecule, we unambiguously show that we can switch the excited electronic state on attosecond timescales, coherently guide the nuclear wave packets to dictate the way a neutral molecule vibrates, and steer and manipulate the ionization and dissociation channels. Furthermore, through advanced theory, we succeed in rigorously modeling multiscale electron and nuclear quantum control in a molecule. The observed richness and complexity of the dynamics, even in this very simplest of molecules, is both remarkable and daunting, and presents intriguing new possibilities for bridging the gap between attosecond physics and attochemistry.
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24
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Abstract
The emergence of an organic/metal interface state is studied for the interface between 3,4,9,10-perylene-tetracarboxylic acid dianhydride (PTCDA) and Ag(100) by means of time- and angle-resolved two-photon photoemission and density functional theory. The interface state is located in the projected band gap of Ag(100), 2.3 eV above the Fermi level, and has an electron lifetime in the 10 fs range. The interface state has no direct counterpart on the clean Ag(100) surface, which only exhibits a broad resonance at ≈1 eV lower energy. Our results thus show that organic overlayers are able to shift such a resonance substantially and even qualitatively change its character to a distinct electronic state at the interface.
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Affiliation(s)
- Martin C E Galbraith
- †Fachbereich Physik, ‡Fachbereich Chemie and Zentrum für Materialwissenschaften, Philipps-Universität Marburg, D-35032 Marburg, Germany
| | - Manuel Marks
- †Fachbereich Physik, ‡Fachbereich Chemie and Zentrum für Materialwissenschaften, Philipps-Universität Marburg, D-35032 Marburg, Germany
| | - Ralf Tonner
- †Fachbereich Physik, ‡Fachbereich Chemie and Zentrum für Materialwissenschaften, Philipps-Universität Marburg, D-35032 Marburg, Germany
| | - Ulrich Höfer
- †Fachbereich Physik, ‡Fachbereich Chemie and Zentrum für Materialwissenschaften, Philipps-Universität Marburg, D-35032 Marburg, Germany
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25
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Shibuta M, Hirata N, Matsui R, Eguchi T, Nakajima A. Charge Separation at the Molecular Monolayer Surface: Observation and Control of the Dynamics. J Phys Chem Lett 2012; 3:981-985. [PMID: 26286559 DOI: 10.1021/jz3002579] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Charge separation dynamics relevant to an electron transfer have been revealed by time- and angle-resolved two-photon photoemission spectroscopy for an n-alkanethiolate self-assembled monolayer (SAM) on a Au(111) surface fabricated by a chemical-wet process. The electron was photoexcited into an image potential state located at 3.7 eV above the Fermi level (EF), and it survived well for more than 100 ps on dodecanethiolate (C12)-SAM. The degree of electron separation is precisely controlled by selecting the length of the alkyl chain (C10-C18). We have also evaluated molecular conductivity at the specific electron energy of EF + 3.7 eV. The tunneling decay parameter, β, was fitted by β90 K = 0.097 Å(-1) and βRT = 0.13 Å(-1). These values were one order smaller than that at around EF by conventional contact probe methods.
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Affiliation(s)
- Masahiro Shibuta
- †Nakajima Designer Nanocluster Assembly Project, JST, ERATO, 3-2-1 Sakado, Takatsu-ku, Kawasaki 213-0012, Japan
- ‡Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Naoyuki Hirata
- ‡Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Ryo Matsui
- ‡Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Toyoaki Eguchi
- †Nakajima Designer Nanocluster Assembly Project, JST, ERATO, 3-2-1 Sakado, Takatsu-ku, Kawasaki 213-0012, Japan
- ‡Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
| | - Atsushi Nakajima
- †Nakajima Designer Nanocluster Assembly Project, JST, ERATO, 3-2-1 Sakado, Takatsu-ku, Kawasaki 213-0012, Japan
- ‡Department of Chemistry, Faculty of Science and Technology, Keio University, 3-14-1 Hiyoshi, Kohoku-ku, Yokohama 223-8522, Japan
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