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Duan HG, Tiwari V, Jha A, Berdiyorov GR, Akimov A, Vendrell O, Nayak PK, Snaith HJ, Thorwart M, Li Z, Madjet ME, Miller RJD. Photoinduced Vibrations Drive Ultrafast Structural Distortion in Lead Halide Perovskite. J Am Chem Soc 2020; 142:16569-16578. [PMID: 32869985 PMCID: PMC7586332 DOI: 10.1021/jacs.0c03970] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
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The success of organic–inorganic
perovskites in optoelectronics
is dictated by the complex interplay between various underlying microscopic
phenomena. The structural dynamics of organic cations and the inorganic
sublattice after photoexcitation are hypothesized to have a direct
effect on the material properties, thereby affecting the overall device
performance. Here, we use ultrafast heterodyne-detected two-dimensional
(2D) electronic spectroscopy to reveal impulsively excited vibrational
modes of methylammonium (MA) lead iodide perovskite, which drive the
structural distortion after photoexcitation. Vibrational analysis
of the measured data allows us to monitor the time-evolved librational
motion of the MA cation along with the vibrational coherences of the
inorganic sublattice. Wavelet analysis of the observed vibrational
coherences reveals the coherent generation of the librational motion
of the MA cation within ∼300 fs complemented with the coherent
evolution of the inorganic skeletal motion. To rationalize this observation,
we employed the configuration interaction singles (CIS), which support
our experimental observations of the coherent generation of librational
motions in the MA cation and highlight the importance of the anharmonic
interaction between the MA cation and the inorganic sublattice. Moreover,
our advanced theoretical calculations predict the transfer of the
photoinduced vibrational coherence from the MA cation to the inorganic
sublattice, leading to reorganization of the lattice to form a polaronic
state with a long lifetime. Our study uncovers the interplay of the
organic cation and inorganic sublattice during formation of the polaron,
which may lead to novel design principles for the next generation
of perovskite solar cell materials.
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Affiliation(s)
- Hong-Guang Duan
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany.,I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstrasse 9, Hamburg 20355, Germany.,The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Vandana Tiwari
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany.,Department of Chemistry, University of Hamburg, Martin-Luther-King Platz 6, Hamburg 20146, Germany
| | - Ajay Jha
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Golibjon R Berdiyorov
- Qatar Environment and Energy Research Institute, Qatar Foundation, Hamad Bin Khalifa University, P.O. Box 34110, Doha, Qatar
| | - Alexey Akimov
- Department of Chemistry, State University of New York at Buffalo, Buffalo New York 14260, United States
| | - Oriol Vendrell
- Physikalisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 229, Heidelberg 69120, Germany
| | - Pabitra K Nayak
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom.,TIFR Centre for Interdisciplinary Sciences, Tata Institute of Fundamental Research, Hyderabad 500046, India
| | - Henry J Snaith
- Department of Physics, University of Oxford, Clarendon Laboratory, Parks Road, Oxford OX1 3PU, United Kingdom
| | - Michael Thorwart
- I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstrasse 9, Hamburg 20355, Germany.,The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, Hamburg 22761, Germany
| | - Zheng Li
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany.,State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China
| | - Mohamed E Madjet
- Qatar Environment and Energy Research Institute, Qatar Foundation, Hamad Bin Khalifa University, P.O. Box 34110, Doha, Qatar
| | - R J Dwayne Miller
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, Hamburg 22761, Germany.,The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, Hamburg 22761, Germany.,The Departments of Chemistry and Physics, University of Toronto, 80 Saint George Street, Toronto, Ontario M5S 3H6, Canada
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2
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Duan HG, Jha A, Li X, Tiwari V, Ye H, Nayak PK, Zhu XL, Li Z, Martinez TJ, Thorwart M, Miller RJD. Intermolecular vibrations mediate ultrafast singlet fission. SCIENCE ADVANCES 2020; 6:eabb0052. [PMID: 32948583 PMCID: PMC7500928 DOI: 10.1126/sciadv.abb0052] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2020] [Accepted: 07/31/2020] [Indexed: 05/20/2023]
Abstract
Singlet fission is a spin-allowed exciton multiplication process in organic semiconductors that converts one spin-singlet exciton to two triplet excitons. It offers the potential to enhance solar energy conversion by circumventing the Shockley-Queisser limit on efficiency. We study the primary steps of singlet fission in a pentacene film by using a combination of TG and 2D electronic spectroscopy complemented by quantum chemical and nonadiabatic dynamics calculations. We show that the coherent vibrational dynamics induces the ultrafast transition from the singlet excited electronic state to the triplet-pair state via a degeneracy of potential energy surfaces, i.e., a multidimensional conical intersection. Significant vibronic coupling of the electronic wave packet to a few key intermolecular rocking modes in the low-frequency region connect the excited singlet and triplet-pair states. Along with high-frequency local vibrations acting as tuning modes, they open a new channel for the ultrafast exciton transfer through the resulting conical intersection.
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Affiliation(s)
- Hong-Guang Duan
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
- I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Ajay Jha
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Xin Li
- Department of Chemistry and PULSE Institute, Stanford University, Stanford, CA 94305, USA
| | - Vandana Tiwari
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany
- Department of Chemistry, University of Hamburg, Martin-Luther-King Platz 6, 20146 Hamburg, Germany
| | - Hanyang Ye
- Clarendon Laboratory, Department of Physics, University of Oxford, Parks Road, Oxford OX1 3PU, UK
| | - Pabitra K Nayak
- TIFR Centre for Interdisciplinary Sciences, 36/P, Gopanpally Village, Ranga Reddy District, Hyderabad 500107, India
| | - Xiao-Lei Zhu
- Department of Chemistry and PULSE Institute, Stanford University, Stanford, CA 94305, USA
| | - Zheng Li
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany.
- State Key Laboratory for Mesoscopic Physics, School of Physics, Peking University, Beijing 100871, China
| | - Todd J Martinez
- Department of Chemistry and PULSE Institute, Stanford University, Stanford, CA 94305, USA
- SLAC National Accelerator Laboratory, Menlo Park, CA 94025, USA
| | - Michael Thorwart
- I. Institut für Theoretische Physik, Universität Hamburg, Jungiusstraße 9, 20355 Hamburg, Germany.
- The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
| | - R J Dwayne Miller
- Max Planck Institute for the Structure and Dynamics of Matter, Luruper Chaussee 149, 22761 Hamburg, Germany.
- The Hamburg Center for Ultrafast Imaging, Luruper Chaussee 149, 22761 Hamburg, Germany
- Departments of Chemistry and Physics, University of Toronto, 80 St. George Street, Toronto, ON M5S 3H6, Canada
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3
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Reislöhner J, Leithold C, Pfeiffer AN. Characterization of weak deep ultraviolet pulses using cross-phase modulation scans. OPTICS LETTERS 2019; 44:1809-1812. [PMID: 30933153 DOI: 10.1364/ol.44.001809] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2019] [Accepted: 03/04/2019] [Indexed: 06/09/2023]
Abstract
Temporal pulse characterization methods can often not be applied to deep ultraviolet (DUV) pulses due to the lack of suitable nonlinear crystals and very low pulse energies. Here, a method is introduced for the characterization of two unknown and independent laser pulses. The applicability is broad, but the method is especially useful for pulses in the DUV, because pulse energies on the picojoule scale suffice. The basis is a spectral analysis of the two interfering DUV pulses, while one of the pulses is phase shifted by an unknown visible-infrared (VIS-IR) pulse via cross-phase modulation. The pulse retrieval is analytic, and the fidelity can be checked by comparing the complex-valued data trace with the retrieved trace.
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Tiwari V, Duan HG, Jha A, Nayak PK, Thorwart M, Snaith HJ, Miller RJD. Evidence and implications for exciton dissociation in lead halide perovskites. EPJ WEB OF CONFERENCES 2019. [DOI: 10.1051/epjconf/201920506018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
We have employed ultrafast transient-grating and two- dimensional electronic spectroscopy to probe dynamics of photo-excited CH3NH3PbI3 thin films with 16-fs temporal resolution. We distinctly capture the 30-fs decay of excitons, weakly coupled to the phonons.
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5
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Towards Accurate Simulation of Two-Dimensional Electronic Spectroscopy. Top Curr Chem (Cham) 2018; 376:24. [DOI: 10.1007/s41061-018-0201-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2017] [Accepted: 04/24/2018] [Indexed: 10/14/2022]
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6
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Jha A, Duan HG, Tiwari V, Thorwart M, Miller RJD. Origin of poor doping efficiency in solution processed organic semiconductors. Chem Sci 2018; 9:4468-4476. [PMID: 29896388 PMCID: PMC5956981 DOI: 10.1039/c8sc00758f] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2018] [Accepted: 04/07/2018] [Indexed: 12/26/2022] Open
Abstract
Doping is an extremely important process where intentional insertion of impurities in semiconductors controls their electronic properties. In organic semiconductors, one of the convenient, but inefficient, ways of doping is the spin casting of a precursor mixture of components in solution, followed by solvent evaporation. Active control over this process holds the key to significant improvements over current poor doping efficiencies. Yet, an optimized control can only come from a detailed understanding of electronic interactions responsible for the low doping efficiencies. Here, we use two-dimensional nonlinear optical spectroscopy to examine these interactions in the course of the doping process by probing the solution mixture of doped organic semiconductors. A dopant accepts an electron from the semiconductor and the two ions form a duplex of interacting charges known as ion-pair complexes. Well-resolved off-diagonal peaks in the two-dimensional spectra clearly demonstrate the electronic connectivity among the ions in solution. This electronic interaction represents a well resolved electrostatically bound state, as opposed to a random distribution of ions. We developed a theoretical model to recover the experimental data, which reveals an unexpectedly strong electronic coupling of ∼250 cm-1 with an intermolecular distance of ∼4.5 Å between ions in solution, which is approximately the expected distance in processed films. The fact that this relationship persists from solution to the processed film gives direct evidence that Coulomb interactions are retained from the precursor solution to the processed films. This memory effect renders the charge carriers equally bound also in the film and, hence, results in poor doping efficiencies. This new insight will help pave the way towards rational tailoring of the electronic interactions to improve doping efficiencies in processed organic semiconductor thin films.
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Affiliation(s)
- Ajay Jha
- Max Planck Institute for the Structure and Dynamics of Matter , Luruper Chaussee 149 , 22761 , Hamburg , Germany .
| | - Hong-Guang Duan
- Max Planck Institute for the Structure and Dynamics of Matter , Luruper Chaussee 149 , 22761 , Hamburg , Germany . .,I. Institut für Theoretische Physik , Universität Hamburg , Jungiusstraße 9 , 20355 Hamburg , Germany.,The Hamburg Center for Ultrafast Imaging , Luruper Chaussee 149 , 22761 Hamburg , Germany
| | - Vandana Tiwari
- Max Planck Institute for the Structure and Dynamics of Matter , Luruper Chaussee 149 , 22761 , Hamburg , Germany . .,Department of Chemistry , University of Hamburg , Martin-Luther-King Platz 6 , 20146 Hamburg , Germany
| | - Michael Thorwart
- I. Institut für Theoretische Physik , Universität Hamburg , Jungiusstraße 9 , 20355 Hamburg , Germany.,The Hamburg Center for Ultrafast Imaging , Luruper Chaussee 149 , 22761 Hamburg , Germany
| | - R J Dwayne Miller
- Max Planck Institute for the Structure and Dynamics of Matter , Luruper Chaussee 149 , 22761 , Hamburg , Germany . .,The Hamburg Center for Ultrafast Imaging , Luruper Chaussee 149 , 22761 Hamburg , Germany.,The Departments of Chemistry and Physics , University of Toronto , 80 St. George Street , Toronto , Canada M5S 3H6
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7
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Duan HG, Prokhorenko VI, Cogdell RJ, Ashraf K, Stevens AL, Thorwart M, Miller RJD. Nature does not rely on long-lived electronic quantum coherence for photosynthetic energy transfer. Proc Natl Acad Sci U S A 2017; 114:8493-8498. [PMID: 28743751 PMCID: PMC5559008 DOI: 10.1073/pnas.1702261114] [Citation(s) in RCA: 179] [Impact Index Per Article: 25.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
During the first steps of photosynthesis, the energy of impinging solar photons is transformed into electronic excitation energy of the light-harvesting biomolecular complexes. The subsequent energy transfer to the reaction center is commonly rationalized in terms of excitons moving on a grid of biomolecular chromophores on typical timescales [Formula: see text]100 fs. Today's understanding of the energy transfer includes the fact that the excitons are delocalized over a few neighboring sites, but the role of quantum coherence is considered as irrelevant for the transfer dynamics because it typically decays within a few tens of femtoseconds. This orthodox picture of incoherent energy transfer between clusters of a few pigments sharing delocalized excitons has been challenged by ultrafast optical spectroscopy experiments with the Fenna-Matthews-Olson protein, in which interference oscillatory signals up to 1.5 ps were reported and interpreted as direct evidence of exceptionally long-lived electronic quantum coherence. Here, we show that the optical 2D photon echo spectra of this complex at ambient temperature in aqueous solution do not provide evidence of any long-lived electronic quantum coherence, but confirm the orthodox view of rapidly decaying electronic quantum coherence on a timescale of 60 fs. Our results can be considered as generic and give no hint that electronic quantum coherence plays any biofunctional role in real photoactive biomolecular complexes. Because in this structurally well-defined protein the distances between bacteriochlorophylls are comparable to those of other light-harvesting complexes, we anticipate that this finding is general and directly applies to even larger photoactive biomolecular complexes.
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Affiliation(s)
- Hong-Guang Duan
- Atomically Resolved Dynamics Department, Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany
- I. Institut für Theoretische Physik, Universität Hamburg, 20355 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, 22761 Hamburg, Germany
| | - Valentyn I Prokhorenko
- Atomically Resolved Dynamics Department, Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany
| | - Richard J Cogdell
- Institute of Molecular, Cell, and Systems Biology, College of Medical, Veterinary, and Life Science, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Khuram Ashraf
- Institute of Molecular, Cell, and Systems Biology, College of Medical, Veterinary, and Life Science, University of Glasgow, Glasgow G12 8QQ, United Kingdom
| | - Amy L Stevens
- Atomically Resolved Dynamics Department, Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging, 22761 Hamburg, Germany
- Department of Chemistry, University of Toronto, Toronto, ON, Canada M5S 3H6
- Department of Physics, University of Toronto, Toronto, ON, Canada M5S 3H6
| | - Michael Thorwart
- I. Institut für Theoretische Physik, Universität Hamburg, 20355 Hamburg, Germany;
- The Hamburg Center for Ultrafast Imaging, 22761 Hamburg, Germany
| | - R J Dwayne Miller
- Atomically Resolved Dynamics Department, Max Planck Institute for the Structure and Dynamics of Matter, 22761 Hamburg, Germany;
- The Hamburg Center for Ultrafast Imaging, 22761 Hamburg, Germany
- Department of Chemistry, University of Toronto, Toronto, ON, Canada M5S 3H6
- Department of Physics, University of Toronto, Toronto, ON, Canada M5S 3H6
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8
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Courtney TL, Fox ZW, Slenkamp KM, Khalil M. Two-dimensional vibrational-electronic spectroscopy. J Chem Phys 2016; 143:154201. [PMID: 26493900 DOI: 10.1063/1.4932983] [Citation(s) in RCA: 48] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Two-dimensional vibrational-electronic (2D VE) spectroscopy is a femtosecond Fourier transform (FT) third-order nonlinear technique that creates a link between existing 2D FT spectroscopies in the vibrational and electronic regions of the spectrum. 2D VE spectroscopy enables a direct measurement of infrared (IR) and electronic dipole moment cross terms by utilizing mid-IR pump and optical probe fields that are resonant with vibrational and electronic transitions, respectively, in a sample of interest. We detail this newly developed 2D VE spectroscopy experiment and outline the information contained in a 2D VE spectrum. We then use this technique and its single-pump counterpart (1D VE) to probe the vibrational-electronic couplings between high frequency cyanide stretching vibrations (νCN) and either a ligand-to-metal charge transfer transition ([Fe(III)(CN)6](3-) dissolved in formamide) or a metal-to-metal charge transfer (MMCT) transition ([(CN)5Fe(II)CNRu(III)(NH3)5](-) dissolved in formamide). The 2D VE spectra of both molecules reveal peaks resulting from coupled high- and low-frequency vibrational modes to the charge transfer transition. The time-evolving amplitudes and positions of the peaks in the 2D VE spectra report on coherent and incoherent vibrational energy transfer dynamics among the coupled vibrational modes and the charge transfer transition. The selectivity of 2D VE spectroscopy to vibronic processes is evidenced from the selective coupling of specific νCN modes to the MMCT transition in the mixed valence complex. The lineshapes in 2D VE spectra report on the correlation of the frequency fluctuations between the coupled vibrational and electronic frequencies in the mixed valence complex which has a time scale of 1 ps. The details and results of this study confirm the versatility of 2D VE spectroscopy and its applicability to probe how vibrations modulate charge and energy transfer in a wide range of complex molecular, material, and biological systems.
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Affiliation(s)
- Trevor L Courtney
- Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195, USA
| | - Zachary W Fox
- Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195, USA
| | - Karla M Slenkamp
- Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195, USA
| | - Munira Khalil
- Department of Chemistry, University of Washington, Box 351700, Seattle, Washington 98195, USA
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Duan HG, Thorwart M. Quantum Mechanical Wave Packet Dynamics at a Conical Intersection with Strong Vibrational Dissipation. J Phys Chem Lett 2016; 7:382-386. [PMID: 26751091 DOI: 10.1021/acs.jpclett.5b02793] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
We derive a reduced model for the nonadiabatic quantum dynamics of an electronic wave packet moving through a conical intersection in the presence of strong vibrational damping. Starting from the dissipative two-state two-model model, we transform the tuning and the coupling mode to the bath. The resulting quantum two-state model with two highly structured environments is solved numerically exactly in the regime of strong vibrational damping. We find negative cross peaks in the ultrafast optical 2D spectra as clear signatures of the conical intersection. They arise from secondary excitations of the wave packet after having passed through the photophysical energy funnel. This feature is in agreement with recent transient absorption measurements of rhodopsin.
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Affiliation(s)
- Hong-Guang Duan
- I. Institut für Theoretische Physik, Universität Hamburg , Jungiusstraße 9, 20355 Hamburg, Germany
- Max Planck-Institute for the Structure and Dynamics of Matter , Luruper Chaussee 149, 22761 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging , Luruper Chaussee 149, 22761 Hamburg, Germany
| | - Michael Thorwart
- I. Institut für Theoretische Physik, Universität Hamburg , Jungiusstraße 9, 20355 Hamburg, Germany
- The Hamburg Center for Ultrafast Imaging , Luruper Chaussee 149, 22761 Hamburg, Germany
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Fuller FD, Ogilvie JP. Experimental implementations of two-dimensional fourier transform electronic spectroscopy. Annu Rev Phys Chem 2015; 66:667-90. [PMID: 25664841 DOI: 10.1146/annurev-physchem-040513-103623] [Citation(s) in RCA: 164] [Impact Index Per Article: 18.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Two-dimensional electronic spectroscopy (2DES) reveals connections between an optical excitation at a given frequency and the signals it creates over a wide range of frequencies. These connections, manifested as cross-peak locations and their lineshapes, reflect the underlying electronic and vibrational structure of the system under study. How these spectroscopic signatures evolve in time reveals the system dynamics and provides a detailed picture of coherent and incoherent processes. 2DES is rapidly maturing and has already found numerous applications, including studies of photosynthetic energy transfer and photochemical reactions and many-body interactions in nanostructured materials. Many systems of interest contain electronic transitions spanning the ultraviolet to the near infrared and beyond. Most 2DES measurements to date have explored a relatively small frequency range. We discuss the challenges of implementing 2DES and compare and contrast different approaches in terms of their information content, ease of implementation, and potential for broadband measurements.
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Affiliation(s)
- Franklin D Fuller
- Department of Physics, University of Michigan, Ann Arbor, Michigan 48109;
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