1
|
Wang J, Zhu R, Zou J, Liu H, Meng H, Zhen Z, Li W, Wang Z, Chen H, Pu Y, Weng Y. Incoherent ultrafast energy transfer in phycocyanin 620 from Thermosynechococcus vulcanus revealed by polarization-controlled two dimensional electronic spectroscopy. J Chem Phys 2024; 161:085101. [PMID: 39171718 DOI: 10.1063/5.0222587] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2024] [Accepted: 08/06/2024] [Indexed: 08/23/2024] Open
Abstract
Phycocyanin 620 (PC620) is the outermost light-harvesting complex in phycobilisome of cyanobacteria, engaged in light collection and energy transfer to the core antenna, allophycocyanin. Recently, long-lived exciton-vibrational coherences have been observed in allophycocyanin, accounting for the coherent energy transfer [Zhu et al., Nat. Commun. 15, 3171 (2024)]. PC620 has a nearly identical spatial location of three α84-β84 phycocyanobilin pigment pairs to those in allophycocyanin, inferring an existence of possible coherent energy transfer pathways. However, whether PC620 undergoes coherent or incoherent energy transfer remains debated. Furthermore, accurate determination of energy transfer rates in PC620 is still necessary owing to the spectral overlap and broadening in conventional time-resolved spectroscopic measurements. In this work, the energy transfer process within PC620 was directly resolved by polarization-controlled two dimensional electronic spectroscopy (2DES) and global analysis. The results show that the energy transfer from α84 to the adjacent β84 has a lifetime constant of 400 fs, from β155 to β84 of 6-8 ps, and from β155 to α84 of 66 ps, fully conforming to the Förster resonance energy transfer mechanism. The circular dichroism spectrum also reveals that the α84-β84 pigment pair does not form excitonic dimer, and the observed oscillatory signals are confirmed to be vibrational coherence, excluding the exciton-vibrational coupling. Nodal line slope analysis of 2DES further reveals that all the vibrational modes participate in the energy dissipation of the excited states. Our results consolidate that the ultrafast energy transfer process in PC620 is incoherent, where the twisted conformation of α84 is suggested as the main cause for preventing the formation of α84-β84 excitonic dimer in contrast to allophycocyanin.
Collapse
Affiliation(s)
- Jiayu Wang
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Ruidan Zhu
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Jiading Zou
- Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, People's Republic of China
| | - Heyuan Liu
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Hanting Meng
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
| | - Zhanghe Zhen
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Wenjun Li
- Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai 264003, People's Republic of China
| | - Zhuan Wang
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
| | - Hailong Chen
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, People's Republic of China
| | - Yang Pu
- School of Agriculture, Ludong University, Yantai 264025, People's Republic of China
| | - Yuxiang Weng
- Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, People's Republic of China
- University of Chinese Academy of Sciences, Beijing 100049, People's Republic of China
- Songshan Lake Materials Laboratory, Dongguan 523808, Guangdong, People's Republic of China
| |
Collapse
|
2
|
Kim P, Roy S, Valentine AJS, Liu X, Kromer S, Kim TW, Li X, Castellano FN, Chen LX. Real-time capture of nuclear motions influencing photoinduced electron transfer. Chem Sci 2024:d4sc01876a. [PMID: 39184296 PMCID: PMC11339639 DOI: 10.1039/d4sc01876a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2024] [Accepted: 08/08/2024] [Indexed: 08/27/2024] Open
Abstract
Although vibronic coupling phenomena have been recognized in the excite state dynamics of transition metal complexes, its impact on photoinduced electron transfer (PET) remains largely unexplored. This study investigates coherent wavepacket (CWP) dynamics during PET processes in a covalently linked electron donor-acceptor complex featuring a cyclometalated Pt(ii) dimer as the donor and naphthalene diimide (NDI) as the acceptors. Upon photoexciting the Pt(ii) dimer electron donor, ultrafast broadband transient absorption spectroscopy revealed direct modulation of NDI radical anion formation through certain CWP motions and correlated temporal evolutions of the amplitudes for these CWPs with the NDI radical anion formation. These results provide clear evidence that the CWP motions are the vibronic coherences coupled to the PET reaction coordinates. Normal mode analysis identified that the CWP motions originate from vibrational modes associated with the dihedral angles and bond lengths between the planes of the cyclometalating ligand and the NDI, the key modes altering their π-interaction, consequently influencing PET dynamics. The findings highlight the pivotal role of vibrations in shaping the favorable trajectories for the efficient PET processes.
Collapse
Affiliation(s)
- Pyosang Kim
- Chemical Sciences and Engineering Division, Argonne National Laboratory Lemont IL 60439 USA
- Chemistry Department, Northwestern University Evanston IL 60208 USA
| | - Subhangi Roy
- Chemistry Department, North Carolina State University Raleigh NC 27695-8204 USA
| | | | - Xiaolin Liu
- Chemistry Department, University of Washington Seattle WA 98195 USA
| | - Sarah Kromer
- Chemistry Department, North Carolina State University Raleigh NC 27695-8204 USA
| | - Tae Wu Kim
- Chemical Sciences and Engineering Division, Argonne National Laboratory Lemont IL 60439 USA
| | - Xiaosong Li
- Chemistry Department, University of Washington Seattle WA 98195 USA
| | - Felix N Castellano
- Chemistry Department, North Carolina State University Raleigh NC 27695-8204 USA
| | - Lin X Chen
- Chemical Sciences and Engineering Division, Argonne National Laboratory Lemont IL 60439 USA
- Chemistry Department, Northwestern University Evanston IL 60208 USA
| |
Collapse
|
3
|
Mai E, Malakar P, Batignani G, Martinati M, Ruhman S, Scopigno T. Orchestrating Nuclear Dynamics in a Permanganate Doped Crystal with Chirped Pump-Probe Spectroscopy. J Phys Chem Lett 2024; 15:6634-6646. [PMID: 38888442 DOI: 10.1021/acs.jpclett.4c00801] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Pump-probe spectroscopy is a powerful tool to investigate light-induced dynamical processes in molecules and solids. Targeting vibrational excitations occurring on the time scales of nuclear motions is challenging, as pulse durations shorter than a vibrational period are needed to initiate the dynamics, and complex experimental schemes are required to isolate weak signatures arising from wavepacket motion in different electronic states. Here, we demonstrate how introducing a temporal delay between the spectral components of femtosecond beams, namely a chirp resulting in the increase of their duration, can counterintuitively boost the desired signals by 2 orders of magnitude. Measuring the time-domain vibrational response of permanganate ions embedded in a KClO4 matrix, we identify an intricate dependence of the vibrational response on pulse chirps and probed wavelength that can be exploited to unveil weak signatures of the doping ions─otherwise dominated by the nonresonant matrix─or to obtain vibrational excitations pertaining only to the excited state, suppressing ground-state contributions.
Collapse
Affiliation(s)
- Emanuele Mai
- Dipartimento di Fisica, Sapienza, Universitá di Roma, Roma I-00185, Italy
- Istituto Italiano di Tecnologia, Center for Life Nano Science @Sapienza, Roma I-00161, Italy
| | - Partha Malakar
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Giovanni Batignani
- Dipartimento di Fisica, Sapienza, Universitá di Roma, Roma I-00185, Italy
- Istituto Italiano di Tecnologia, Center for Life Nano Science @Sapienza, Roma I-00161, Italy
| | - Miles Martinati
- Dipartimento di Fisica, Sapienza, Universitá di Roma, Roma I-00185, Italy
| | - Sanford Ruhman
- Institute of Chemistry, The Hebrew University of Jerusalem, Jerusalem 9190401, Israel
| | - Tullio Scopigno
- Dipartimento di Fisica, Sapienza, Universitá di Roma, Roma I-00185, Italy
- Graphene Laboratories, Istituto Italiano di Tecnologia, Genova I-16163, Italy
| |
Collapse
|
4
|
Green D, Bressan G, Heisler IA, Meech SR, Jones GA. Vibrational coherences in half-broadband 2D electronic spectroscopy: Spectral filtering to identify excited state displacements. J Chem Phys 2024; 160:234104. [PMID: 38884412 DOI: 10.1063/5.0214023] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2024] [Accepted: 06/03/2024] [Indexed: 06/18/2024] Open
Abstract
Vibrational coherences in ultrafast pump-probe (PP) and 2D electronic spectroscopy (2DES) provide insights into the excited state dynamics of molecules. Femtosecond coherence spectra and 2D beat maps yield information about displacements of excited state surfaces for key vibrational modes. Half-broadband 2DES uses a PP configuration with a white light continuum probe to extend the detection range and resolve vibrational coherences in the excited state absorption (ESA). However, the interpretation of these spectra is difficult as they are strongly dependent on the spectrum of the pump laser and the relative displacement of the excited states along the vibrational coordinates. We demonstrate the impact of these convoluting factors for a model based upon cresyl violet. A careful consideration of the position of the pump spectrum can be a powerful tool in resolving the ESA coherences to gain insights into excited state displacements. This paper also highlights the need for caution in considering the spectral window of the pulse when interpreting these spectra.
Collapse
Affiliation(s)
- Dale Green
- Physics, Faculty of Science, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Giovanni Bressan
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Ismael A Heisler
- Instituto de Física, Universidade Federal do Rio Grande do Sul, 91509-900 Porto Alegre, RS, Brazil
| | - Stephen R Meech
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| | - Garth A Jones
- School of Chemistry, University of East Anglia, Norwich NR4 7TJ, United Kingdom
| |
Collapse
|
5
|
Myers CA, Lu SY, Shedge S, Pyuskulyan A, Donahoe K, Khanna A, Shi L, Isborn CM. Axial H-Bonding Solvent Controls Inhomogeneous Spectral Broadening, While Peripheral H-Bonding Solvent Controls Vibronic Broadening: Cresyl Violet in Methanol. J Phys Chem B 2024; 128:5685-5699. [PMID: 38832562 DOI: 10.1021/acs.jpcb.4c01401] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/05/2024]
Abstract
The dynamics of the nuclei of both a chromophore and its condensed-phase environment control many spectral features, including the vibronic and inhomogeneous broadening present in spectral line shapes. For the cresyl violet chromophore in methanol, we here analyze and isolate the effect of specific chromophore-solvent interactions on simulated spectral densities, reorganization energies, and linear absorption spectra. Employing both chromophore and its condensed-phase environment control many spectral features, including the vibronic and inhomogeneous broadening present in spectral line shapes. For the cresyl violet chromophore in methanol, we here analyze and isolate the effect of specific chromophore-solvent interactions on simulated spectral densities, reorganization energies, and linear absorption spectra. Employing both force field and ab initio molecular dynamics trajectories along with the inclusion of only certain solvent molecules in the excited-state calculations, we determine that the methanol molecules axial to the chromophore are responsible for the majority of inhomogeneous broadening, with a single methanol molecule that forms an axial hydrogen bond dominating the response. The strong peripheral hydrogen bonds do not contribute to spectral broadening, as they are very stable throughout the dynamics and do not lead to increased energy-gap fluctuations. We also find that treating the strong peripheral hydrogen bonds as molecular mechanical point charges during the molecular dynamics simulation underestimates the vibronic coupling. Including these peripheral hydrogen bonding methanol molecules in the quantum-mechanical region in a geometry optimization increases the vibronic coupling, suggesting that a more advanced treatment of these strongly interacting solvent molecules during the molecular dynamics trajectory may be necessary to capture the full vibronic spectral broadening.
Collapse
Affiliation(s)
- Christopher A Myers
- Department of Chemistry and Biochemistry, University of California Merced, Merced, California 95343, United States
| | - Shao-Yu Lu
- Department of Chemistry and Biochemistry, University of California Merced, Merced, California 95343, United States
| | - Sapana Shedge
- Department of Chemistry and Biochemistry, University of California Merced, Merced, California 95343, United States
| | - Arthur Pyuskulyan
- Department of Chemistry and Biochemistry, University of California Merced, Merced, California 95343, United States
| | - Katherine Donahoe
- Department of Chemistry and Biochemistry, University of California Merced, Merced, California 95343, United States
| | - Ajay Khanna
- Department of Chemistry and Biochemistry, University of California Merced, Merced, California 95343, United States
| | - Liang Shi
- Department of Chemistry and Biochemistry, University of California Merced, Merced, California 95343, United States
| | - Christine M Isborn
- Department of Chemistry and Biochemistry, University of California Merced, Merced, California 95343, United States
| |
Collapse
|
6
|
Kong J, Kuang Z, Zhang W, Song Y, Yao G, Zhang C, Wang H, Luo Y, Zhou M. Robust vibrational coherence protected by a core-shell structure in silver nanoclusters. Chem Sci 2024; 15:6906-6915. [PMID: 38725488 PMCID: PMC11077528 DOI: 10.1039/d4sc00009a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2024] [Accepted: 03/31/2024] [Indexed: 05/12/2024] Open
Abstract
Vibrational coherence has attracted considerable research interests because of its potential functions in light harvesting systems. Although positive signs of vibrational coherence in metal nanoclusters have been observed, the underlying mechanism remains to be verified. Here, we demonstrate that robust vibrational coherence with a lifetime of 1 ps can be clearly identified in Ag44(SR)30 core-shell nanoclusters, in which an icosahedral Ag12 core is well protected by a dodecahedral Ag20 cage. Ultrafast spectroscopy reveals that two vibrational modes at around 2.4 THz and 1.6 THz, corresponding to the breathing mode and quadrupolar-like mode of the icosahedral Ag12 core, respectively, are responsible for the generation of vibrational coherence. In addition, the vibrational coherence of Ag44 has an additional high frequency mode (2.4 THz) when compared with that of Ag29, in which there is only one low frequency vibration mode (1.6 THz), and the relatively faster dephasing in two-layer Ag29 relative to that in Ag44 further supports the fact that the robust vibrational coherence in Ag44 is ascribed to its unique matryoshka-like core-shell structure. Our findings not only present unambiguous experimental evidence for a multi-layer core-shell structure protected vibrational coherence under ambient conditions but also offers a practical strategy for the design of highly efficient quantum optoelectronic devices.
Collapse
Affiliation(s)
- Jie Kong
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China Hefei Anhui 230026 P. R. China
| | - Zhuoran Kuang
- State Key Laboratory of Information Photonic and Optical Communications, School of Science Beijing University of Posts and Telecommunications (BUPT) Beijing 100876 P. R. China
| | - Wei Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China Hefei Anhui 230026 P. R. China
| | - Yongbo Song
- School of Biomedical Engineering, Research and Engineering Center of Biomedical Materials, Anhui Medical University Hefei Anhui 230032 P. R. China
| | - Guo Yao
- National Laboratory of Solid State Microstructures, School of Physics, Collaborative Innovation Center for 5Advanced Microstructures, Nanjing University Nanjing 210093 P. R. China
| | - Chunfeng Zhang
- National Laboratory of Solid State Microstructures, School of Physics, Collaborative Innovation Center for 5Advanced Microstructures, Nanjing University Nanjing 210093 P. R. China
| | - He Wang
- Department of Physics, University of Miami Coral Gables Florida 33146 USA
| | - Yi Luo
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China Hefei Anhui 230026 P. R. China
| | - Meng Zhou
- Hefei National Research Center for Physical Sciences at the Microscale, University of Science and Technology of China Hefei Anhui 230026 P. R. China
| |
Collapse
|
7
|
Bressan G, Green D, Jones GA, Heisler IA, Meech SR. Two-Dimensional Electronic Spectroscopy Resolves Relative Excited-State Displacements. J Phys Chem Lett 2024; 15:2876-2884. [PMID: 38447068 PMCID: PMC10945572 DOI: 10.1021/acs.jpclett.3c03420] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/06/2023] [Revised: 02/09/2024] [Accepted: 03/01/2024] [Indexed: 03/08/2024]
Abstract
Knowledge of relative displacements between potential energy surfaces (PES) is critical in spectroscopy and photochemistry. Information on displacements is encoded in vibrational coherences. Here we apply ultrafast two-dimensional electronic spectroscopy in a pump-probe half-broadband (HB2DES) geometry to probe the ground- and excited-state potential landscapes of cresyl violet. 2D coherence maps reveal that while the coherence amplitude of the dominant 585 cm-1 Raman-active mode is mainly localized in the ground-state bleach and stimulated emission regions, a 338 cm-1 mode is enhanced in excited-state absorption. Modeling these data with a three-level displaced harmonic oscillator model using the hierarchical equation of motion-phase matching approach (HEOM-PMA) shows that the S1 ← S0 PES displacement is greater along the 585 cm-1 coordinate than the 338 cm-1 coordinate, while Sn ← S1 displacements are similar along both coordinates. HB2DES is thus a powerful tool for exploiting nuclear wavepackets to extract quantitative multidimensional, vibrational coordinate information across multiple PESs.
Collapse
Affiliation(s)
- Giovanni Bressan
- School
of Chemistry, Norwich Research Park, University
of East Anglia, Norwich NR4 7TJ, United
Kingdom
| | - Dale Green
- School
of Chemistry, Norwich Research Park, University
of East Anglia, Norwich NR4 7TJ, United
Kingdom
| | - Garth A. Jones
- School
of Chemistry, Norwich Research Park, University
of East Anglia, Norwich NR4 7TJ, United
Kingdom
| | - Ismael A. Heisler
- Instituto
de Fisica, Universidade Federal do Rio Grande
do Sul, 91509-900 Porto Alegre, RS, Brazil
| | - Stephen R. Meech
- School
of Chemistry, Norwich Research Park, University
of East Anglia, Norwich NR4 7TJ, United
Kingdom
| |
Collapse
|
8
|
Rafiq S, Weingartz NP, Kromer S, Castellano FN, Chen LX. Spin-vibronic coherence drives singlet-triplet conversion. Nature 2023; 620:776-781. [PMID: 37468632 DOI: 10.1038/s41586-023-06233-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 05/18/2023] [Indexed: 07/21/2023]
Abstract
Design-specific control over the transitions between excited electronic states with different spin multiplicities is of the utmost importance in molecular and materials chemistry1-3. Previous studies have indicated that the combination of spin-orbit and vibronic effects, collectively termed the spin-vibronic effect, can accelerate quantum-mechanically forbidden transitions at non-adiabatic crossings4,5. However, it has been difficult to identify precise experimental manifestations of the spin-vibronic mechanism. Here we present coherence spectroscopy experiments that reveal the interplay between the spin, electronic and vibrational degrees of freedom that drive efficient singlet-triplet conversion in four structurally related dinuclear Pt(II) metal-metal-to-ligand charge-transfer (MMLCT) complexes. Photoexcitation activates the formation of a Pt-Pt bond, launching a stretching vibrational wavepacket. The molecular-structure-dependent decoherence and recoherence dynamics of this wavepacket resolve the spin-vibronic mechanism. We find that vectorial motion along the Pt-Pt stretching coordinates tunes the singlet and intermediate-state energy gap irreversibly towards the conical intersection and subsequently drives formation of the lowest stable triplet state in a ratcheting fashion. This work demonstrates the viability of using vibronic coherences as probes6-9 to clarify the interplay among spin, electronic and nuclear dynamics in spin-conversion processes, and this could inspire new modular designs to tailor the properties of excited states.
Collapse
Affiliation(s)
- Shahnawaz Rafiq
- Department of Chemistry, Northwestern University, Evanston, IL, USA
| | - Nicholas P Weingartz
- Department of Chemistry, Northwestern University, Evanston, IL, USA
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA
| | - Sarah Kromer
- Department of Chemistry, North Carolina State University, Raleigh, NC, USA
| | - Felix N Castellano
- Department of Chemistry, North Carolina State University, Raleigh, NC, USA.
| | - Lin X Chen
- Department of Chemistry, Northwestern University, Evanston, IL, USA.
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL, USA.
| |
Collapse
|
9
|
Jeffries WR, Malola S, Tofanelli MA, Ackerson CJ, Häkkinen H, Knappenberger KL. Coherent Vibrational Dynamics of Au 144(SC 8H 9) 60 Nanoclusters. J Phys Chem Lett 2023:6679-6685. [PMID: 37463467 DOI: 10.1021/acs.jpclett.3c01477] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/20/2023]
Abstract
The coherent vibrational dynamics of Au144(SC8H9)60, obtained from femtosecond time-resolved transient absorption spectroscopy, are described. Two acoustic modes were identified and assigned, including 2.0 THz breathing and 0.7 THz quadrupolar vibrations. These assignments are consistent with predictions using classical mechanics models, indicating that bulk models accurately describe the vibrational properties of Au144(SC8H9)60. Coherent phonon signals were persistent for up to 3 ps, indicating energy dissipation by the nanocluster was the primary dephasing channel. The initial excitation phases of the breathing and quadrupolar modes were π-phase-shifted, reflecting differences in the displacive nuclear motion of the vibrations. The combined agreement of the vibrational frequencies, relative phases, and decoherence times supported predictions based on classical models. The vibrational frequencies were insensitive to silver substitution for gold but did show increased inhomogeneous damping of the coherent phonons. The ability to predict the vibrational properties of metal nanoclusters can have an impact on nanoresonator and mass sensing technologies.
Collapse
Affiliation(s)
- William R Jeffries
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Sami Malola
- Department of Physics, Nanoscience Center, University of Jyväskylä, Fl-40014 Jyväskylä, Finland
| | - Marcus A Tofanelli
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Christopher J Ackerson
- Department of Chemistry, Colorado State University, Fort Collins, Colorado 80523, United States
| | - Hannu Häkkinen
- Department of Physics, Nanoscience Center, University of Jyväskylä, Fl-40014 Jyväskylä, Finland
- Department of Chemistry, Nanoscience Center, University of Jyväskylä, Fl-40014 Jyväskylä, Finland
| | - Kenneth L Knappenberger
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, United States
| |
Collapse
|
10
|
Absolute excited state molecular geometries revealed by resonance Raman signals. Nat Commun 2022; 13:7770. [PMID: 36522323 PMCID: PMC9755279 DOI: 10.1038/s41467-022-35099-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2022] [Accepted: 11/18/2022] [Indexed: 12/23/2022] Open
Abstract
Ultrafast reactions activated by light absorption are governed by multidimensional excited-state (ES) potential energy surfaces (PESs), which describe how the molecular potential varies with the nuclear coordinates. ES PESs ad-hoc displaced with respect to the ground state can drive subtle structural rearrangements, accompanying molecular biological activity and regulating physical/chemical properties. Such displacements are encoded in the Franck-Condon overlap integrals, which in turn determine the resonant Raman response. Conventional spectroscopic approaches only access their absolute value, and hence cannot determine the sense of ES displacements. Here, we introduce a two-color broadband impulsive Raman experimental scheme, to directly measure complex Raman excitation profiles along desired normal modes. The key to achieve this task is in the signal linear dependence on the Frank-Condon overlaps, brought about by non-degenerate resonant probe and off-resonant pump pulses, which ultimately enables time-domain sensitivity to the phase of the stimulated vibrational coherences. Our results provide the tool to determine the magnitude and the sensed direction of ES displacements, unambiguously relating them to the ground state eigenvectors reference frame.
Collapse
|
11
|
Zhou J, Liu H, Liu S, Su P, Wang W, Li Z, Liu Z, Chen Y, Dong Y, Li X. Singlet Fission in Colloidal Nanoparticles of Amphipathic Diketopyrrolopyrrole Derivatives: Probing the Role of the Charge Transfer State. J Phys Chem B 2022; 126:6483-6492. [PMID: 35979942 DOI: 10.1021/acs.jpcb.2c03163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To evaluate the role of the charge transfer (CT) state in the singlet fission (SF) process, we prepared three 3,6-bis(thiophen-2-yl)diketopyrrolopyrrole (TDPP) derivatives with zero (Ph2TDPP), one (Ph2TDPP-COOH), and two (Ph2TDPP-(COOH)2) carboxylic groups, respectively. Their colloidal nanoparticles were also prepared by a simple precipitation method. The SF dynamics and mechanism in these colloid nanoparticles were investigated by using steady-state/transient absorption and fluorescence spectroscopy. Steady-state absorption spectra reveal that the strength of the CT resonance interactions between the adjacent DPP units is increased gradually from Ph2TDPP to Ph2TDPP-COOH and then to Ph2TDPP-(COOH)2. Fluorescence and transient absorption spectra demonstrate that SF is proceeded via a CT-assisted superexchange mechanism in these three nanoparticles. Furthermore, SF rate and yield are enhanced gradually with the increase of the number of the carboxylic group, which may be attributed to the enhancement of the CT coupling strength. The result of this work not only provides a better understanding of the SF mechanism especially for the role of the CT state but also gives some new insights for the design of efficient SF materials based on DPP derivatives.
Collapse
Affiliation(s)
- Jun Zhou
- College of Chemical Engineering, School of Materials Science and Engineering, College of New Energy, China University of Petroleum (East China), Qingdao, Shandong 266580, China
| | - Heyuan Liu
- College of Chemical Engineering, School of Materials Science and Engineering, College of New Energy, China University of Petroleum (East China), Qingdao, Shandong 266580, China.,National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China
| | - Shanshan Liu
- College of Chemical Engineering, School of Materials Science and Engineering, College of New Energy, China University of Petroleum (East China), Qingdao, Shandong 266580, China
| | - Pengkun Su
- College of Chemical Engineering, School of Materials Science and Engineering, College of New Energy, China University of Petroleum (East China), Qingdao, Shandong 266580, China
| | - Weijie Wang
- College of Chemical Engineering, School of Materials Science and Engineering, College of New Energy, China University of Petroleum (East China), Qingdao, Shandong 266580, China
| | - Zhi Li
- Shandong Energy Group Co., Ltd., Jinan, Shandong 250014, China
| | - Zhaobin Liu
- Shandong Energy Group Co., Ltd., Jinan, Shandong 250014, China
| | - Yanli Chen
- College of Chemical Engineering, School of Materials Science and Engineering, College of New Energy, China University of Petroleum (East China), Qingdao, Shandong 266580, China
| | - Yunqin Dong
- College of Chemical Engineering and Materials Science, Zaozhuang University, Zaozhuang 277160, China
| | - Xiyou Li
- College of Chemical Engineering, School of Materials Science and Engineering, College of New Energy, China University of Petroleum (East China), Qingdao, Shandong 266580, China
| |
Collapse
|
12
|
Zhang W, Kong J, Li Y, Kuang Z, Wang H, Zhou M. Coherent vibrational dynamics of Au 144(SR) 60 nanoclusters. Chem Sci 2022; 13:8124-8130. [PMID: 35919416 PMCID: PMC9278113 DOI: 10.1039/d2sc02246j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2022] [Accepted: 06/16/2022] [Indexed: 11/26/2022] Open
Abstract
The coherent vibrational dynamics of gold nanoclusters (NCs) provides important information on the coupling between vibrations and electrons as well as their mechanical properties, which is critical for understanding the evolution from a metallic state to a molecular state with diminishing size. Coherent vibrations have been widely explored in small-sized atomically precise gold NCs, while it remains a challenge to observe them in large-sized gold NCs. In this work, we report the coherent vibrational dynamics of atomically precise Au144(SR)60 NCs via temperature-dependent femtosecond transient absorption (TA) spectroscopy. The population dynamics of Au144(SR)60 consists of three relaxation processes: internal conversion, core-shell charge transfer and relaxation to the ground state. After removing the population dynamics from the TA kinetics, fast Fourier transform analysis on the residual oscillation reveals distinct vibrational modes at 1.5 THz (50 cm-1) and 2 THz (67 cm-1), which arise from the wavepacket motions along the ground-state and excited-state potential energy surfaces (PES), respectively. These results are helpful for understanding the physical properties of gold nanostructures with a threshold size that lies in between those of molecular-like NCs and metallic-state nanoparticles.
Collapse
Affiliation(s)
- Wei Zhang
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China Hefei Anhui 230026 China
| | - Jie Kong
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China Hefei Anhui 230026 China
| | - Yingwei Li
- Department of Chemistry and Chemical Biology, Harvard University 12 Oxford Street Cambridge Massachusetts 02138 USA
| | - Zhuoran Kuang
- School of Science, Beijing University of Posts and Telecommunications (BUPT) Beijing 100876 P. R. China
| | - He Wang
- Department of Physics, University of Miami Coral Gables Florida 33146 USA
| | - Meng Zhou
- Hefei National Research Center for Physical Sciences at the Microscale, Department of Chemical Physics, University of Science and Technology of China Hefei Anhui 230026 China
- Department of Physics, University of Miami Coral Gables Florida 33146 USA
| |
Collapse
|
13
|
Barclay M, Huff JS, Pensack RD, Davis PH, Knowlton WB, Yurke B, Dean JC, Arpin PC, Turner DB. Characterizing Mode Anharmonicity and Huang-Rhys Factors Using Models of Femtosecond Coherence Spectra. J Phys Chem Lett 2022; 13:5413-5423. [PMID: 35679146 PMCID: PMC9234982 DOI: 10.1021/acs.jpclett.1c04162] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2021] [Accepted: 06/06/2022] [Indexed: 06/15/2023]
Abstract
Femtosecond laser pulses readily produce coherent quantum beats in transient-absorption spectra. These oscillatory signals often arise from molecular vibrations and therefore may contain information about the excited-state potential energy surface near the Franck-Condon region. Here, by fitting the measured spectra of two laser dyes to microscopic models of femtosecond coherence spectra (FCS) arising from molecular vibrations, we classify coherent quantum-beat signals as fundamentals or overtones and quantify their Huang-Rhys factors and anharmonicity values. We discuss the extracted Huang-Rhys factors in the context of quantum-chemical computations. This work solidifies the use of FCS for analysis of coherent quantum beats arising from molecular vibrations, which will aid studies of molecular aggregates and photosynthetic proteins.
Collapse
Affiliation(s)
- Matthew
S. Barclay
- Micron
School for Materials Science and Engineering, Boise State University, Boise, Idaho 83725, United States
| | - Jonathan S. Huff
- Micron
School for Materials Science and Engineering, Boise State University, Boise, Idaho 83725, United States
| | - Ryan D. Pensack
- Micron
School for Materials Science and Engineering, Boise State University, Boise, Idaho 83725, United States
| | - Paul H. Davis
- Micron
School for Materials Science and Engineering, Boise State University, Boise, Idaho 83725, United States
| | - William B. Knowlton
- Micron
School for Materials Science and Engineering, Boise State University, Boise, Idaho 83725, United States
- Department
of Electrical & Computer Engineering, Boise State University, Boise, Idaho 83725, United States
| | - Bernard Yurke
- Micron
School for Materials Science and Engineering, Boise State University, Boise, Idaho 83725, United States
- Department
of Electrical & Computer Engineering, Boise State University, Boise, Idaho 83725, United States
| | - Jacob C. Dean
- Department
of Physical Science, Southern Utah University, Cedar City, Utah 84720, United States
| | - Paul C. Arpin
- Department
of Physics, California State University,
Chico, Chico, California 95929, United States
| | - Daniel B. Turner
- Micron
School for Materials Science and Engineering, Boise State University, Boise, Idaho 83725, United States
| |
Collapse
|
14
|
Paulus BC, McCusker JK. On the use of vibronic coherence to identify reaction coordinates for ultrafast excited-state dynamics of transition metal-based chromophores. Faraday Discuss 2022; 237:274-299. [PMID: 35661840 DOI: 10.1039/d2fd00106c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The question of whether one can use information from quantum coherence as a means of identifying vibrational degrees of freedom that are active along an excited-state reaction coordinate is discussed. Specifically, we are exploring the notion of whether quantum oscillations observed in single-wavelength kinetics data exhibiting coherence dephasing times that are intermediate between that expected for either pure electronic or pure vibrational dephasing are vibronic in nature and therefore may be coupled to electronic state-to-state evolution. In the case of a previously published Fe(II) polypyridyl complex, coherences observed subsequent to 1A1 → 1MLCT excitation were linked to large-amplitude motion of a portion of the ligand framework; dephasing times on the order of 200-300 fs suggested that these degrees of freedom could be associated with ultrafast (∼100 fs) conversion from the initially formed MLCT excited state to lower-energy, metal-centered ligand-field excited state(s) of the compound. Incorporation of an electronically benign but sterically restrictive Cu(I) ion into the superstructure designed to interfere with this motion yielded a compound exhibiting a ∼25-fold increase in the compound's MLCT lifetime, a result that was interpreted as confirmation of the initial hypothesis. However, new data acquired on a different chemical system - Cr(acac')3 (where acac' represents various derivatives of acetylacetonate) - yielded results that call into question this same hypothesis. Coherences observed subsequent to 4A2 → 4T2 ligand-field excitation on a series of molecules implicated similar vibrational degrees of freedom across the series, but exhibited dephasing times ranging from 340 fs to 2.5 ps without any clear correlation to the dynamics of excited-state evolution in the system. Taken together, the results obtained on both of these chemical platforms suggest that while identification of coherences can indeed point to degrees of freedom that should be considered as candidate modes for defining reaction trajectories, our understanding of the factors that determine the interplay across coherences, dephasing times, and electronic and geometric structure is insufficient at the present time to view this parameter as a robust metric for differentiating active versus spectator modes for ultrafast dynamics.
Collapse
Affiliation(s)
- Bryan C Paulus
- Department of Chemistry, Michigan State University, 578 South Shaw Lane, East Lansing, MI 48824, USA.
| | - James K McCusker
- Department of Chemistry, Michigan State University, 578 South Shaw Lane, East Lansing, MI 48824, USA.
| |
Collapse
|
15
|
Kim P, Valentine AJS, Roy S, Mills AW, Castellano FN, Li X, Chen LX. Ultrafast branching in intersystem crossing dynamics revealed by coherent vibrational wavepacket motions in a bimetallic Pt(II) complex. Faraday Discuss 2022; 237:259-273. [PMID: 35642929 DOI: 10.1039/d2fd00009a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultrafast excited state processes of transition metal complexes (TMCs) are governed by complicated interplays between electronic and nuclear dynamics, which demand a detailed understanding to achieve optimal functionalities of photoactive TMC-based materials for many applications. In this work, we investigated a cyclometalated platinum(II) dimer known to undergo a Pt-Pt bond contraction in the metal-metal-to-ligand-charge-transfer (MMLCT) excited state using femtosecond broadband transient absorption (fs-BBTA) spectroscopy in combination with geometry optimization and normal mode calculations. Using a sub-20 fs pump and broadband probe pulses in fs-BBTA spectroscopy, we were able to correlate the coherent vibrational wavepacket (CVWP) evolution with the stimulated emission (SE) dynamics of the 1MMLCT state. The results demonstrated that the 145 cm-1 CVWP motions with the damping times of ∼0.9 ps and ∼2 ps originate from coherent Pt-Pt stretching vibrations in the singlet and triplet MMLCT states, respectively. On the basis of excited state potential energy surface calculations in our previous work, we rationalized that the CVWP transfer from the Franck-Condon (FC) state to the 3MMLCT state was mediated by a triplet ligand-centered (3LC) intermediate state through two step intersystem crossing (ISC) on a time scale shorter than a period of the Pt-Pt stretching wavepacket motions. Moreover, it was found that the CVWP motion had 110 cm-1 frequency decays with the damping time of ∼0.2 ps, matching the time constant of 0.253 ps, corresponding to a redshift in the SE feature at early times. This observation indicates that the Pt-Pt bond contraction changes the stretching frequency from 110 to 145 cm-1 and stabilizes the 1MMLCT state relative to the 3LC state with a ∼0.2 ps time scale. Thus, the ultrafast ISC from the 1MMLCT to the 3LC states occurs before the Pt-Pt bond shortening. The findings herein provide insight into understanding the impact of Pt-Pt bond contraction on the ultrafast branching of the 1MMLCT population into the direct (1MMLCT → 3MMLCT) and indirect ISC pathways (1MMLCT → 3LC → 3MMLCT) in the Pt(II) dimer. These results revealed intricate excited state electronic and nuclear motions that could steer the reaction pathways with a level of detail that has not been achieved before.
Collapse
Affiliation(s)
- Pyosang Kim
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA. .,Chemical Science and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60349, USA
| | - Andrew J S Valentine
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Subhangi Roy
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | - Alexis W Mills
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Felix N Castellano
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | - Xiaosong Li
- Department of Chemistry, University of Washington, Seattle, Washington 98195, USA
| | - Lin X Chen
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, USA. .,Chemical Science and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60349, USA
| |
Collapse
|
16
|
Bin Mohd Yusof MS, Song H, Debnath T, Lowe B, Yang M, Loh ZH. Ultrafast proton transfer of the aqueous phenol radical cation. Phys Chem Chem Phys 2022; 24:12236-12248. [PMID: 35579397 DOI: 10.1039/d2cp00505k] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Proton transfer (PT) reactions are fundamental to numerous chemical and biological processes. While sub-picosecond PT involving electronically excited states has been extensively studied, little is known about ultrafast PT triggered by photoionization. Here, we employ femtosecond optical pump-probe spectroscopy and quantum dynamics calculations to investigate the ultrafast proton transfer dynamics of the aqueous phenol radical cation (PhOH˙+). Analysis of the vibrational wave packet dynamics reveals unusually short dephasing times of 0.18 ± 0.02 ps and 0.16 ± 0.02 ps for the PhOH˙+ O-H wag and bend frequencies, respectively, suggestive of ultrafast PT occurring on the ∼0.1 ps timescale. The reduced potential energy surface obtained from ab initio calculations shows that PT is barrierless when it is coupled to the intermolecular hindered translation between PhOH˙+ and the proton-acceptor water molecule. Quantum dynamics calculations yield a lifetime of 193 fs for PhOH˙+, in good agreement with the experimental results and consistent with the PT reaction being mediated by the intermolecular O⋯O stretch. These results suggest that photoionization can be harnessed to produce photoacids that undergo ultrafast PT. In addition, they also show that PT can serve as an ultrafast deactivation channel for limiting the oxidative damage potential of radical cations.
Collapse
Affiliation(s)
- Muhammad Shafiq Bin Mohd Yusof
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.
| | - Hongwei Song
- State Key Laboratory for Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China
| | - Tushar Debnath
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.
| | - Bethany Lowe
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.
| | - Minghui Yang
- State Key Laboratory for Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Innovation Academy for Precision Measurement Science and Technology, Chinese Academy of Sciences, Wuhan 430071, China.,Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan 430071, China
| | - Zhi-Heng Loh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.
| |
Collapse
|
17
|
Zhang RM, Xu X, Truhlar DG. Observing Intramolecular Vibrational Energy Redistribution via the Short-Time Fourier Transform. J Phys Chem A 2022; 126:3006-3014. [PMID: 35522826 DOI: 10.1021/acs.jpca.1c09905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Intramolecular vibrational energy relaxation (IVR) is important in many problems in chemical physics. Here, we apply the short-time Fourier transform method for analyzing IVR with classical dynamics. Calculating time-dependent Fourier transforms to perform such an analysis requires extending the usual Fourier transform method, and we do that here. The guiding concept behind the generalization is that if there is a shift of vibrational energy from one frequency range to another, we see a difference between the spectrum before the shift and the spectrum after the shift. We use time-window functions to transform the power spectrum of a trajectory into a time-dependent density spectrum of the average kinetic energy. The time-dependent average kinetic energy for each interval of the spectrum becomes an indicator to monitor the extent and nature of the energy transfer into and out of the corresponding modes. We illustrate this method for the H2O molecule. By analyzing cases with different initial conditions, we show that the short-time Fourier transform method can distinguish trends in IVR that depend on the initial distribution of energy and not just on the total energy.
Collapse
Affiliation(s)
- Rui Ming Zhang
- Center for Combustion Energy, Department of Energy and Power Engineering, and Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China.,Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| | - Xuefei Xu
- Center for Combustion Energy, Department of Energy and Power Engineering, and Key Laboratory for Thermal Science and Power Engineering of Ministry of Education, Tsinghua University, Beijing 100084, China
| | - Donald G Truhlar
- Department of Chemistry, Chemical Theory Center, and Minnesota Supercomputing Institute, University of Minnesota, Minneapolis, Minnesota 55455-0431, United States
| |
Collapse
|
18
|
Hong Y, Kim W, Kim T, Kaufmann C, Kim H, Würthner F, Kim D. Real-time Observation of Structural Dynamics Triggering Excimer Formation in a Perylene Bisimide Folda-dimer by Ultrafast Time-Domain Raman Spectroscopy. Angew Chem Int Ed Engl 2022; 61:e202114474. [PMID: 35075813 PMCID: PMC9306572 DOI: 10.1002/anie.202114474] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Indexed: 01/31/2023]
Abstract
In π-conjugated organic photovoltaic materials, an excimer state has been generally regarded as a trap state which hinders efficient excitation energy transport. But despite wide investigations of the excimer for overcoming the undesirable energy loss, the understanding of the relationship between the structure of the excimer in stacked organic compounds and its properties remains elusive. Here, we present the landscape of structural dynamics from the excimer formation to its relaxation in a co-facially stacked archetypical perylene bisimide folda-dimer using ultrafast time-domain Raman spectroscopy. We directly captured vibrational snapshots illustrating the ultrafast structural evolution triggering the excimer formation along the interchromophore coordinate on the complex excited-state potential surfaces and following evolution into a relaxed excimer state. Not only does this work showcase the ultrafast structural dynamics necessary for the excimer formation and control of excimer characteristics but also provides important criteria for designing the π-conjugated organic molecules.
Collapse
Affiliation(s)
- Yongseok Hong
- Department of ChemistrySpectroscopy Laboratory for Functional π-Electronic SystemsYonsei University03722SeoulRepublic of Korea
| | - Woojae Kim
- Department of ChemistrySpectroscopy Laboratory for Functional π-Electronic SystemsYonsei University03722SeoulRepublic of Korea
- Department of Chemistry and Chemical BiologyCornell UniversityIthaca14853New YorkUSA
| | - Taeyeon Kim
- Department of ChemistrySpectroscopy Laboratory for Functional π-Electronic SystemsYonsei University03722SeoulRepublic of Korea
- The Institute for Sustainability and Energy at NorthwesternNorthwestern UniversityEvanston60208IllinoisUSA
| | - Christina Kaufmann
- Institut für Organische Chemie & Center for Nanosystems ChemistryUniversitat WürzburgAm Hubland97074WürzburgGermany
| | - Hyungjun Kim
- Department of ChemistryIncheon National University119 Academy-ro, Yeonsu-gu22012IncheonRepublic of Korea
| | - Frank Würthner
- Institut für Organische Chemie & Center for Nanosystems ChemistryUniversitat WürzburgAm Hubland97074WürzburgGermany
| | - Dongho Kim
- Department of ChemistrySpectroscopy Laboratory for Functional π-Electronic SystemsYonsei University03722SeoulRepublic of Korea
| |
Collapse
|
19
|
Ross AM, Osella S, Policht VR, Zheng M, Maggini M, Marangi F, Cerullo G, Gatti T, Scotognella F. Deciphering Photoinduced Charge Transfer Dynamics in a Cross-Linked Graphene-Dye Nanohybrid. THE JOURNAL OF PHYSICAL CHEMISTRY. C, NANOMATERIALS AND INTERFACES 2022; 126:3569-3581. [PMID: 35242271 PMCID: PMC8883522 DOI: 10.1021/acs.jpcc.1c10570] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Revised: 02/04/2022] [Indexed: 06/14/2023]
Abstract
The search for synthetic materials that mimic natural photosynthesis by converting solar energy into other more useful forms of energy is an ever-growing research endeavor. Graphene-based materials, with their exceptional electronic and optical properties, are exemplary candidates for high-efficiency solar energy harvesting devices. High photoactivity can be conveniently achieved by functionalizing graphene with small molecule organic semiconductors whose band-gaps can be tuned by structural modification, leading to interactions between the π-conjugated electronic systems in both the semiconductor and graphene. Here we investigate the ultrafast transient optical properties of a cross-linked graphene-dye (diphenyl-dithiophenediketopyrrolopyrrole) nanohybrid material, in which oligomers of the organic semiconductor dye are covalently bound to a random network of few-layer graphene flakes, and compare the results to those obtained for the reference dye monomer. Using a combination of ultrafast transient absorption and two-dimensional electronic spectroscopy, we provide substantial evidence for photoinduced charge transfer that occurs within 18 ps in the nanohybrid system. Notably, subpicosecond photoinduced torsional relaxation observed in the constituent dye monomer is absent in the cross-linked nanohybrid system. Through density functional theory calculations, we compare the competing effects of covalent bonding, increasing conjugation length, and the presence of multiple graphene flakes. We find evidence that the observed ultrafast charge transfer process occurs through a superexchange mechanism in which the oligomeric dye bridge provides virtual states enabling charge transfer between graphene-dye covalent bond sites.
Collapse
Affiliation(s)
- Aaron M. Ross
- Department
of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Silvio Osella
- Chemical
and Biological Systems Simulation Lab, Centre of New Technologies, University of Warsaw, Banacha 2C, 02-097 Warsaw, Poland
| | - Veronica R. Policht
- Department
of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Meng Zheng
- Chemical
Sciences Department, Università degli
Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Michele Maggini
- Chemical
Sciences Department, Università degli
Studi di Padova, Via Marzolo 1, 35131 Padova, Italy
| | - Fabio Marangi
- Department
of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- Center
for Nano Science and Technology, Istituto
Italiano di Tecnologia, Via Pascolo, 70/3 Milano 20133, Italy
| | - Giulio Cerullo
- Department
of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Teresa Gatti
- Center
for Materials Research, Justus Liebig University, Heinrich-Buff-Ring 17, 35392, Giessen, Germany
| | - Francesco Scotognella
- Department
of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
- Center
for Nano Science and Technology, Istituto
Italiano di Tecnologia, Via Pascolo, 70/3 Milano 20133, Italy
| |
Collapse
|
20
|
Dhamija S, Bhutani G, Jayachandran A, De AK. A Revisit on Impulsive Stimulated Raman Spectroscopy: Importance of Spectral Dispersion of Chirped Broadband Probe. J Phys Chem A 2022; 126:1019-1032. [PMID: 35142494 DOI: 10.1021/acs.jpca.1c10566] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The usefulness of a chirped broadband probe and spectral dispersion to obtain Raman spectra under nonresonant/resonant impulsive excitation is revisited. A general methodology is presented that inherently takes care of phasing the time-domain low-frequency oscillations without probe pulse compression and retrieves the absolute phase of the oscillations. As test beds, neat solvents (CCl4, CHCl3, and CH2Cl2) are used. Observation of periodic intensity modulation along detection wavelengths for particular modes is explained using a simple electric field interaction picture. This method is extended to diatomic molecule (iodine) and polyatomic molecules (Nile blue and methylene blue) to assign vibrational frequencies in ground/excited electronic state that are supported by density functional theory calculations. A comparison between frequency-domain and time-domain counterparts, i.e., stimulated Raman scattering and impulsive stimulated Raman scattering using degenerate pump-probe pairs is presented, and most importantly, it is shown how impulsive stimulated Raman scattering using chirped broadband probe retains unique advantages offered by both.
Collapse
Affiliation(s)
- Shaina Dhamija
- Condensed Phase Dynamics Group, Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Punjab 140306, India
| | - Garima Bhutani
- Condensed Phase Dynamics Group, Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Punjab 140306, India
| | - Ajay Jayachandran
- Condensed Phase Dynamics Group, Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Punjab 140306, India
| | - Arijit K De
- Condensed Phase Dynamics Group, Department of Chemical Sciences, Indian Institute of Science Education and Research Mohali, Knowledge City, Sector 81, SAS Nagar, Punjab 140306, India
| |
Collapse
|
21
|
Hong Y, Kim W, Kim T, Kaufmann C, Kim H, Würthner F, Kim D. Real‐time Observation of Structural Dynamics Triggering Excimer Formation in a Perylene Bisimide Folda‐dimer by Ultrafast Time‐Domain Raman Spectroscopy. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202114474] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Affiliation(s)
- Yongseok Hong
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Republic of Korea
| | - Woojae Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Republic of Korea
- Department of Chemistry and Chemical Biology Cornell University Ithaca 14853 New York USA
| | - Taeyeon Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Republic of Korea
- The Institute for Sustainability and Energy at Northwestern Northwestern University Evanston 60208 Illinois USA
| | - Christina Kaufmann
- Institut für Organische Chemie & Center for Nanosystems Chemistry Universitat Würzburg Am Hubland 97074 Würzburg Germany
| | - Hyungjun Kim
- Department of Chemistry Incheon National University 119 Academy-ro, Yeonsu-gu 22012 Incheon Republic of Korea
| | - Frank Würthner
- Institut für Organische Chemie & Center for Nanosystems Chemistry Universitat Würzburg Am Hubland 97074 Würzburg Germany
| | - Dongho Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Republic of Korea
| |
Collapse
|
22
|
Biswas S, Kim J, Zhang X, Scholes GD. Coherent Two-Dimensional and Broadband Electronic Spectroscopies. Chem Rev 2022; 122:4257-4321. [PMID: 35037757 DOI: 10.1021/acs.chemrev.1c00623] [Citation(s) in RCA: 38] [Impact Index Per Article: 19.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023]
Abstract
Over the past few decades, coherent broadband spectroscopy has been widely used to improve our understanding of ultrafast processes (e.g., photoinduced electron transfer, proton transfer, and proton-coupled electron transfer reactions) at femtosecond resolution. The advances in femtosecond laser technology along with the development of nonlinear multidimensional spectroscopy enabled further insights into ultrafast energy transfer and carrier relaxation processes in complex biological and material systems. New discoveries and interpretations have led to improved design principles for optimizing the photophysical properties of various artificial systems. In this review, we first provide a detailed theoretical framework of both coherent broadband and two-dimensional electronic spectroscopy (2DES). We then discuss a selection of experimental approaches and considerations of 2DES along with best practices for data processing and analysis. Finally, we review several examples where coherent broadband and 2DES were employed to reveal mechanisms of photoinitiated ultrafast processes in molecular, biological, and material systems. We end the review with a brief perspective on the future of the experimental techniques themselves and their potential to answer an even greater range of scientific questions.
Collapse
Affiliation(s)
- Somnath Biswas
- Department of Chemistry, Princeton University, Princeton, New Jersey 08 544, United States
| | - JunWoo Kim
- Department of Chemistry, Princeton University, Princeton, New Jersey 08 544, United States
| | - Xinzi Zhang
- Department of Chemistry, Princeton University, Princeton, New Jersey 08 544, United States
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Princeton, New Jersey 08 544, United States
| |
Collapse
|
23
|
Bressan G, Jirasek M, Roy P, Anderson HL, Meech SR, Heisler IA. Population and Coherence Dynamics in Large Conjugated Porphyrin Nanorings. Chem Sci 2022; 13:9624-9636. [PMID: 36091893 PMCID: PMC9400675 DOI: 10.1039/d2sc01971j] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 07/12/2022] [Indexed: 11/28/2022] Open
Abstract
In photosynthesis, nature exploits the distinctive electronic properties of chromophores arranged in supramolecular rings for efficient light harvesting. Among synthetic supramolecular cyclic structures, porphyrin nanorings have attracted considerable attention as they have a resemblance to naturally occurring light-harvesting structures but offer the ability to control ring size and the level of disorder. Here, broadband femtosecond transient absorption spectroscopy, with pump pulses in resonance with either the high or the low energy sides of the inhomogeneously broadened absorption spectrum, is used to study the population dynamics and ground and excited state vibrational coherence in large porphyrin nanorings. A series of fully conjugated, alkyne bridged, nanorings constituted of between ten and forty porphyrin units is studied. Pump-wavelength dependent fast spectral evolution is found. A fast rise or decay of the stimulated emission is found when large porphyrin nanorings are excited on, respectively, the high or low energy side of the absorption spectrum. Such dynamics are consistent with the hypothesis of a variation in transition dipole moment across the inhomogeneously broadened ground state ensemble. The observed dynamics indicate the interplay of nanoring conformation and oscillator strength. Oscillatory dynamics on the sub-ps time domain are observed in both pumping conditions. A combined analysis of the excitation wavelength-dependent transient spectra along with the amplitude and phase evolution of the oscillations allows assignment to vibrational wavepackets evolving on either ground or excited states electronic potential energy surfaces. Even though porphyrin nanorings support highly delocalized electronic wavefunctions, with coherence length spanning tens of chromophores, the measured vibrational coherences remain localised on the monomers. The main contributions to the beatings are assigned to two vibrational modes localised on the porphyrin cores: a Zn–N stretching mode and a skeletal methinic/pyrrolic C–C stretching and in-plane bending mode. Pump wavelength-dependent, ultrafast excited state dynamics arising from inhomogeneous broadening and ground and excited state nuclear wavepackets were observed for a series of Zn porphyrin nanorings made of 10 to 40 repeating units.![]()
Collapse
Affiliation(s)
- Giovanni Bressan
- School of Chemistry Norwich Research Park, University of East Anglia Norwich NR4 7TJ UK
| | - Michael Jirasek
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory Oxford OX1 3TA UK
| | - Palas Roy
- School of Chemistry Norwich Research Park, University of East Anglia Norwich NR4 7TJ UK
| | - Harry L Anderson
- Department of Chemistry, University of Oxford, Chemistry Research Laboratory Oxford OX1 3TA UK
| | - Stephen R Meech
- School of Chemistry Norwich Research Park, University of East Anglia Norwich NR4 7TJ UK
| | - Ismael A Heisler
- Instituto de Física, Universidade Federal do Rio Grande do Sul Avenida Bento Gonçalves, 9500, CEP 91501-970 Porto Alegre Brazil
| |
Collapse
|
24
|
Batignani G, Sansone C, Ferrante C, Fumero G, Mukamel S, Scopigno T. Excited-State Energy Surfaces in Molecules Revealed by Impulsive Stimulated Raman Excitation Profiles. J Phys Chem Lett 2021; 12:9239-9247. [PMID: 34533307 PMCID: PMC8488957 DOI: 10.1021/acs.jpclett.1c02209] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 08/16/2021] [Indexed: 05/14/2023]
Abstract
Photophysical and photochemical processes are ruled by the interplay between transient vibrational and electronic degrees of freedom, which are ultimately determined by the multidimensional potential energy surfaces (PESs). Differences between ground and excited PESs are encoded in the relative intensities of resonant Raman bands, but they are experimentally challenging to access, requiring measurements at multiple wavelengths under identical conditions. Herein, we perform a two-color impulsive vibrational scattering experiment to launch nuclear wavepacket motions by an impulsive pump and record their coupling with a targeted excited-state potential by resonant Raman processes with a delayed probe, generating in a single measurement background-free vibrational spectra across the entire sample absorption. Building on the interference between the multiple pathways resonant with the excited-state manifold that generate the Raman signal, we show how to experimentally tune their relative phase by varying the probe chirp, decoding nuclear displacements along different normal modes and revealing the multidimensional PESs. Our results are validated against time-dependent density functional theory.
Collapse
Affiliation(s)
- Giovanni Batignani
- Dipartimento
di Fisica, Universitá di Roma “La
Sapienza”, Roma I-00185, Italy
- Istituto
Italiano di Tecnologia, Center for Life Nano Science @Sapienza, Roma I-00161, Italy
| | - Carlotta Sansone
- Dipartimento
di Fisica, Universitá di Roma “La
Sapienza”, Roma I-00185, Italy
| | - Carino Ferrante
- Dipartimento
di Fisica, Universitá di Roma “La
Sapienza”, Roma I-00185, Italy
- Istituto
Italiano di Tecnologia, Center for Life Nano Science @Sapienza, Roma I-00161, Italy
| | - Giuseppe Fumero
- Dipartimento
di Fisica, Universitá di Roma “La
Sapienza”, Roma I-00185, Italy
| | - Shaul Mukamel
- Department
of Chemistry, University of California, Irvine, California 92623, United States
| | - Tullio Scopigno
- Dipartimento
di Fisica, Universitá di Roma “La
Sapienza”, Roma I-00185, Italy
- Istituto
Italiano di Tecnologia, Center for Life Nano Science @Sapienza, Roma I-00161, Italy
| |
Collapse
|
25
|
Zhou M, Du X, Wang H, Jin R. The Critical Number of Gold Atoms for a Metallic State Nanocluster: Resolving a Decades-Long Question. ACS NANO 2021; 15:13980-13992. [PMID: 34490772 DOI: 10.1021/acsnano.1c04705] [Citation(s) in RCA: 31] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Probing the transition from a metallic state to a molecular state in gold nanoparticles is fundamentally important for understanding the origin of surface plasmon resonance and the nature of the metallic bond. Atomically precise gold nanoclusters are desired for probing such a transition based upon a series of precise sizes with X-ray structures. While the definition of the metallic state in nanoclusters is simple, that is, when the HOMO-LUMO gap (Eg) becomes negligibly small (Eg < kBT, where kB is the Boltzmann constant and T the temperature), the experimental determination of ultrasmall Eg (e.g., of kBT level) is difficult, and the thermal excitation of valence electrons apparently comes into play in ultrasmall Eg nanoclusters. Although a sharp transition from nonmetallic Au246(SR)80 to metallic Au279(SR)84 (SR: thiolate) has been observed, there is still uncertainty about the transition region. Here, we summarize several criteria on determining the metallic state versus the molecular (or nonmetallic) state in gold nanoclusters, including (1) Eg determined by optical and electrochemical methods, (2) steady-state absorption spectra, (3) cryogenic optical spectra, (4) transient absorption spectra, (5) excited-state lifetime and power dependence, and (6) coherent oscillations in ultrafast electron dynamics. We emphasize that multiple analyses should be performed and cross-checked in practice because no single criterion is definitive. We also review the photophysics of several gold nanoclusters with nascent surface plasmon resonance. These criteria are expected to deepen the understanding of the metallic to molecular state transition of gold and other metal nanoclusters and also promote the design of functional nanomaterials and their applications.
Collapse
Affiliation(s)
- Meng Zhou
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
- Department of Physics, University of Miami, Coral Gables, Florida 33146, United States
| | - Xiangsha Du
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| | - He Wang
- Department of Physics, University of Miami, Coral Gables, Florida 33146, United States
| | - Rongchao Jin
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States
| |
Collapse
|
26
|
van Stokkum IHM, Kloz M, Polli D, Viola D, Weißenborn J, Peerbooms E, Cerullo G, Kennis JTM. Vibronic dynamics resolved by global and target analysis of ultrafast transient absorption spectra. J Chem Phys 2021; 155:114113. [PMID: 34551543 DOI: 10.1063/5.0060672] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
We present a methodology that provides a complete parametric description of the time evolution of the electronically and vibrationally excited states as detected by ultrafast transient absorption (TA). Differently from previous approaches, which started fitting the data after ≈100 fs, no data are left out in our methodology, and the "coherent artifact" and the instrument response function are fully taken into account. In case studies, the method is applied to solvents, the dye Nile blue, and all-trans β-carotene in cyclohexane solution. The estimated Damped Oscillation Associated Spectra (DOAS) and phases express the most important vibrational frequencies present in the molecular system. By global fit alone of the experimental data, it is difficult to interpret in detail the underlying dynamics. Since it is unfeasible to directly fit the data by a theoretical simulation, our enhanced DOAS methodology thus provides a useful "middle ground" where the theoretical description and the fit of the experimental data can meet. β-carotene in cyclohexane was complementarily studied with femtosecond stimulated Raman spectroscopy (FSRS). The fs-ps dynamics of β-carotene in cyclohexane in TA and FSRS experiments can be described by a sequential scheme S2 → hot S1 → S1' → S1 → S0 with lifetimes of 167 fs (fixed), 0.35, 1.1, and 9.6 ps. The correspondence of DOAS decaying concomitantly with hot S1 and the Species Associated Difference Spectra of hot S1 in TA and FSRS suggest that we observe here features of the vibrational relaxation and nuclear reorganization responsible for the hot S1 to S1 transition.
Collapse
Affiliation(s)
- Ivo H M van Stokkum
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Miroslav Kloz
- Institute of Physics, ELI Beamlines, Academy of Sciences of the Czech Republic, CZ-18221 Prague, Czech Republic
| | - Dario Polli
- IFN-CNR, Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Daniele Viola
- IFN-CNR, Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - Jörn Weißenborn
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Ebo Peerbooms
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Giulio Cerullo
- IFN-CNR, Department of Physics, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano, Italy
| | - John T M Kennis
- Department of Physics and Astronomy and LaserLaB, Faculty of Science, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| |
Collapse
|
27
|
Yoneda Y, Kudisch B, Rather SR, Maiuri M, Nagasawa Y, Scholes GD, Miyasaka H. Vibrational Dephasing along the Reaction Coordinate of an Electron Transfer Reaction. J Am Chem Soc 2021; 143:14511-14522. [PMID: 34474559 DOI: 10.1021/jacs.1c01863] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The role of molecular vibration in photoinduced electron transfer (ET) reactions has been extensively debated in recent years. In this study, we investigated vibrational wavepacket dynamics in a model ET system consisting of an organic dye molecule as an electron acceptor dissolved in various electron donating solvents. By using broad band pump-probe (BBPP) spectroscopy with visible laser pulses of sub-10 fs duration, coherent vibrational wavepackets of naphthacene dye with frequencies spanning 170-1600 cm-1 were observed in the time domain. The coherence properties of 11 vibrational modes were analyzed by an inverse Fourier filtering procedure, and we discovered that the dephasing times of some vibrational coherences are reduced with increasing ET rates. Density functional theory calculations indicated that the corresponding vibrational modes have a large Huang-Rhys factor between the reactant and the product states, supporting the hypothesis that the loss of phase coherence along certain vibrational modes elucidates that those vibrations are coupled to the reaction coordinate of an ET reaction.
Collapse
Affiliation(s)
- Yusuke Yoneda
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| | - Bryan Kudisch
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Shahnawaz R. Rather
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Margherita Maiuri
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Yutaka Nagasawa
- Department of Applied Chemistry, College of Life Sciences, Ritsumeikan University, 1-1-1 Nojihigashi, Kusatsu 525-8577, Japan
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States
| | - Hiroshi Miyasaka
- Graduate School of Engineering Science, Osaka University, Toyonaka, Osaka 560-8531, Japan
| |
Collapse
|
28
|
Bin Mohd Yusof MS, Lim YL, Loh ZH. Ultrafast vibrational wave packet dynamics of the aqueous tyrosyl radical anion induced by photodetachment. Phys Chem Chem Phys 2021; 23:18525-18534. [PMID: 34581329 DOI: 10.1039/d1cp02975d] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
The ultrafast dynamics triggered by the photodetachment of the tyrosinate dianion in aqueous environment shed light on the elementary processes that accompany the interaction of ionizing radiation with biological matter. Photodetachment of the tryosinate dianion yields the tyrosyl radical anion, an important intermediate in biological redox reactions, although the study of its ultrafast dynamics is limited. Here, we utilize femtosecond optical pump-probe spectroscopy to investigate the ultrafast structural reorganization dynamics that follow the photodetachment of the tyrosinate dianion in aqueous solution. Photodetachment of the tyrosinate dianion leads to vibrational wave packet motion along seven vibrational modes that are coupled to the photodetachment process. The vibrational modes are assigned with the aid of density functional theory (DFT) calculations. Our results offer a glimpse of the elementary dynamics of ionized biomolecules and suggest the possibility of extending this approach to investigate the ionization-induced structural rearrangement of other aromatic amino acids and larger biomolecules.
Collapse
Affiliation(s)
- Muhammad Shafiq Bin Mohd Yusof
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.
| | - Yong Liang Lim
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.
| | - Zhi-Heng Loh
- Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371, Singapore.
| |
Collapse
|
29
|
Zhou M, Jin R. Optical Properties and Excited-State Dynamics of Atomically Precise Gold Nanoclusters. Annu Rev Phys Chem 2021; 72:121-142. [PMID: 33297734 DOI: 10.1146/annurev-physchem-090419-104921] [Citation(s) in RCA: 26] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Understanding the excited-state dynamics of nanomaterials is essential to their applications in photoenergy storage and conversion. This review summarizes recent progress in the excited-state dynamics of atomically precise gold (Au) nanoclusters (NCs). We first discuss the electronic structure and typical relaxation pathways of Au NCs from subpicoseconds to microseconds. Unlike plasmonic Au nanoparticles, in which collective electron excitation dominates, Au NCs show single-electron transitions and molecule-like exciton dynamics. The size-, shape-, structure-, and composition-dependent dynamics in Au NCs are further discussed in detail. For small-sized Au NCs, strong quantum confinement effects give rise to relaxation dynamics that is significantly dependent on atomic packing, shape, and heteroatom doping. For relatively larger-sized Au NCs, strong size dependence can be observed in exciton and electron dynamics. We also discuss the origin of coherent oscillations and their roles in excited-state relaxation. Finally, we provide our perspective on future directions in this area.
Collapse
Affiliation(s)
- Meng Zhou
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA;
| | - Rongchao Jin
- Department of Chemistry, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, USA;
| |
Collapse
|
30
|
Rather SR, Fu B, Kudisch B, Scholes GD. Interplay of vibrational wavepackets during an ultrafast electron transfer reaction. Nat Chem 2021; 13:70-76. [PMID: 33288893 DOI: 10.1038/s41557-020-00607-9] [Citation(s) in RCA: 41] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 11/10/2020] [Indexed: 01/05/2023]
Abstract
Electron transfer reactions facilitate energy transduction and photoredox processes in biology and chemistry. Recent findings show that molecular vibrations can enable the dramatic acceleration of some electron transfer reactions, and control it by suppressing and enhancing reaction paths. Here, we report ultrafast spectroscopy experiments and quantum dynamics simulations that resolve how quantum vibrations participate in an electron transfer reaction. We observe ballistic electron transfer (~30 fs) along a reaction coordinate comprising high-frequency promoting vibrations. Along another vibrational coordinate, the system becomes impulsively out of equilibrium as a result of the electron transfer reaction. This leads to the generation (by the electron transfer reaction, not the laser pulse) of a new vibrational coherence along this second reaction coordinate in a mode associated with the reaction product. These results resolve a complex reaction trajectory composed of multiple vibrational coordinates that, like a sequence of ratchets, progressively diminish the recurrence of the reactant state.
Collapse
Affiliation(s)
| | - Bo Fu
- Department of Chemistry, Princeton University, Princeton, NJ, USA
| | - Bryan Kudisch
- Department of Chemistry, Princeton University, Princeton, NJ, USA
| | | |
Collapse
|
31
|
Zhu R, Zou J, Wang Z, Chen H, Weng Y. Electronic State-Resolved Multimode-Coupled Vibrational Wavepackets in Oxazine 720 by Two-Dimensional Electronic Spectroscopy. J Phys Chem A 2020; 124:9333-9342. [PMID: 33136407 DOI: 10.1021/acs.jpca.0c06559] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The difference between the excited- and ground-state vibrational wavepackets remains to be fully explored when multiple vibrational modes are coherently excited simultaneously by femtosecond pulses. In this work, we present a series of one- and two-dimensional electronic spectroscopy for studying multimode wavepackets of oxazine 720 in solution. Fourier transform (FT) maps combined with time-frequency transform (TFT) are employed to unambiguously distinguish the origin of low-frequency vibrational wavepackets, that is, an excited-state vibrational wavepacket of 586 cm-1 with a dephasing time of 0.7 ps and a ground-state vibrational wavepacket of 595 cm-1 with a dephasing time of 1.3-1.7 ps. We also found the additional low-frequency vibrational wavepackets resulting from the coupling of the 595 cm-1 mode to a series of high-frequency modes centered at 1150 cm-1 via electronic transitions. The combined use of FT maps and TFT analysis allows us to reveal the potential vibrational coupling of wavepackets and offers the possibility of disentangling the coupling between the electronic and vibrational degrees of freedom in condensed-phase systems.
Collapse
Affiliation(s)
- Ruidan Zhu
- Beijing National Laboratory for Condensed Matter Physics, Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiading Zou
- Beijing National Laboratory for Condensed Matter Physics, Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhuan Wang
- Beijing National Laboratory for Condensed Matter Physics, Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China
| | - Hailong Chen
- Beijing National Laboratory for Condensed Matter Physics, Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| | - Yuxiang Weng
- Beijing National Laboratory for Condensed Matter Physics, Laboratory of Soft Matter Physics, Institute of Physics, Chinese Academy of Sciences, Beijing 100190, China.,University of Chinese Academy of Sciences, Beijing 100049, China.,Songshan Lake Materials Laboratory, Dongguan, Guangdong 523808, China
| |
Collapse
|
32
|
Batignani G, Ferrante C, Scopigno T. Accessing Excited State Molecular Vibrations by Femtosecond Stimulated Raman Spectroscopy. J Phys Chem Lett 2020; 11:7805-7813. [PMID: 32841039 PMCID: PMC7735730 DOI: 10.1021/acs.jpclett.0c01971] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 08/25/2020] [Indexed: 05/08/2023]
Abstract
Excited state vibrations are crucial for determining the photophysical and photochemical properties of molecular compounds. Stimulated Raman scattering can coherently stimulate and probe molecular vibrations with optical pulses, but it is generally restricted to ground state properties. Working under resonance conditions enables cross-section enhancement and selective excitation to a targeted electronic level but is hampered by an increased signal complexity due to the presence of overlapping spectral contributions. Here, we show how detailed information about ground and excited state vibrations can be disentangled by exploiting the relative time delay between Raman and probe pulses to control the excited state population, combined with a diagrammatic formalism to dissect the pathways concurring with the signal generation. The proposed method is then exploited to elucidate the vibrational properties of the ground and excited electronic states in the paradigmatic case of cresyl violet. We anticipate that the presented approach holds the potential for selective mapping of the reaction coordinates pertaining to transient electronic stages implied in photoactive compounds.
Collapse
Affiliation(s)
- Giovanni Batignani
- Dipartimento
di Fisica, Universitá di Roma “La
Sapienza”, Roma I-00185, Italy
| | - Carino Ferrante
- Dipartimento
di Fisica, Universitá di Roma “La
Sapienza”, Roma I-00185, Italy
- Center
for Life Nano Science @Sapienza, Istituto
Italiano di Tecnologia, Roma I-00161, Italy
- Graphene
Labs, Istituto Italiano di Tecnologia, Genova I-16163, Italy
| | - Tullio Scopigno
- Dipartimento
di Fisica, Universitá di Roma “La
Sapienza”, Roma I-00185, Italy
- Center
for Life Nano Science @Sapienza, Istituto
Italiano di Tecnologia, Roma I-00161, Italy
- Graphene
Labs, Istituto Italiano di Tecnologia, Genova I-16163, Italy
| |
Collapse
|
33
|
Lu J, Lee Y, Anna JM. Extracting the Frequency-Dependent Dynamic Stokes Shift from Two-Dimensional Electronic Spectra with Prominent Vibrational Coherences. J Phys Chem B 2020; 124:8857-8867. [DOI: 10.1021/acs.jpcb.0c05522] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- Jiawei Lu
- University of Pennsylvania, 231 South 34 Street, Philadelphia, Pennsylvania 19104, United States
| | - Yumin Lee
- University of Pennsylvania, 231 South 34 Street, Philadelphia, Pennsylvania 19104, United States
| | - Jessica M. Anna
- University of Pennsylvania, 231 South 34 Street, Philadelphia, Pennsylvania 19104, United States
| |
Collapse
|
34
|
Fitzpatrick C, Odhner JH, Levis RJ. Spectral Signatures of Ground- and Excited-State Wavepacket Interference after Impulsive Excitation. J Phys Chem A 2020; 124:6856-6866. [PMID: 32786657 DOI: 10.1021/acs.jpca.0c03912] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Impulsive transient absorption spectroscopy is used to track the formation and evolution of vibrational coherences in cresyl violet perchlorate under different excitation conditions. Resonant and off-resonant pump pulses result in the selective formation of excited (S1)- and ground (S0)-state wavepackets. Partially resonant and broadband excitation conditions lead to the simultaneous formation of wavepackets in the ground and excited states. The wavepackets are characterized by the phase-flips in the coherent signal associated with wavepacket motion across the absorption and emission maxima and by a red shift of 2-10 cm-1 in the Raman features of the excited state compared to the ground-state wavepacket. We observe that, when wavepackets are simultaneously excited on the ground- and excited-state surfaces, interference on a picosecond timescale between coherent oscillations in the two wavepackets gives rise to features that cannot be attributed to the passage of a wavepacket through a conical intersection, such as shifting phase-flips and zero-amplitude nodes. Wavepacket filtering using windowed Fourier transforms highlights these interference effects and demonstrates that special care must be taken in order to properly interpret data that have been processed in this manner.
Collapse
Affiliation(s)
- Colin Fitzpatrick
- Center for Advanced Photonics Research, Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Johanan H Odhner
- Center for Advanced Photonics Research, Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, Pennsylvania 19122, United States
| | - Robert J Levis
- Center for Advanced Photonics Research, Department of Chemistry, Temple University, 1901 N. 13th Street, Philadelphia, Pennsylvania 19122, United States
| |
Collapse
|
35
|
Leveraging excited-state coherence for synthetic control of ultrafast dynamics. Nature 2020; 582:214-218. [DOI: 10.1038/s41586-020-2353-2] [Citation(s) in RCA: 49] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2019] [Accepted: 03/13/2020] [Indexed: 11/08/2022]
|
36
|
Ramakrishnan V, Nabetani Y, Yamamoto D, Tachibana H, Inoue H. Heat trapping in a nano-layered microenvironment: estimation of temperature by thermal sensing molecules. Phys Chem Chem Phys 2020; 22:7201-7209. [PMID: 32141449 DOI: 10.1039/c9cp05817f] [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
We have previously found reversible photo-induced expansion and contraction of organic/inorganic clay hybrids, and even sliding of niobate nano-sheets at the macroscopic level of organic/inorganic niobate hybrids, induced by the molecular photo-isomerization of the polyfluoroalkylated azobenzene derivative (C3F-Azo-C6H) intercalated within the interlayer, which is viewed as an artificial muscle model unit. Based on systematic investigations of the steady state photo-isomerization and transient behavior of the reaction, we comprehended that the phenomena is caused by trapping of excess energy liberated during the isomerization, as well as the relaxation processes upon excitation of azobenzene chromophores in the interlayers of the hybrid. In this paper, quantitative estimation of transient 'heat' trapped in various microenvironments has been studied by each co-intercalation of temperature sensing dye molecules - rhodamine B (RhB) or tris(bipyridine)ruthenium(ii) chloride (Rubpy) with C3F-Azo-C6H within clay (SSA) nano-layers. The amount of dye molecules co-intercalated was kept to trace amounts that did not alter the bi-layered structure of the hybrid. The temperature of the microenvironment surrounding the probe molecules was estimated from the emission lifetime analysis. The evidently reduced emission lifetimes in C3F-Azo-C6H/SSA and C3H-Azo-C6H/SSA hybrids in the film state, indicated the elevation of temperature of the microenvironment upon excitation of the chromophores, which demonstrated our previous hypothesis rationalizing that the high reactivity of isomerization in the hybrid film state is caused by heat trapping via multi-step dissipation of the excess energy. With the hybrid of a hydrocarbon analogue (C3H-Azo-C6H), a distinct difference in temperature gradient was found to show the crucial role of the perfluoroalkyl chain of the surfactant that traps the excess energy to retard its dissipation leading to three-dimensional morphological motion.
Collapse
Affiliation(s)
- Vivek Ramakrishnan
- Department of Applied Chemistry, Graduate School of Urban Environmental Sciences, Tokyo Metropolitan University, 1-1, Minami-ohsawa, Hachioji, Tokyo 192-0397, Japan.
| | | | | | | | | |
Collapse
|
37
|
Ultrafast structural rearrangement dynamics induced by the photodetachment of phenoxide in aqueous solution. Nat Commun 2019; 10:2944. [PMID: 31270331 PMCID: PMC6610110 DOI: 10.1038/s41467-019-10989-1] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2019] [Accepted: 06/14/2019] [Indexed: 01/28/2023] Open
Abstract
The elementary processes that accompany the interaction of ionizing radiation with biologically relevant molecules are of fundamental importance. However, the ultrafast structural rearrangement dynamics induced by the ionization of biomolecules in aqueous solution remain hitherto unknown. Here, we employ femtosecond optical pump-probe spectroscopy to elucidate the vibrational wave packet dynamics that follow the photodetachment of phenoxide, a structural mimic of tyrosine, in aqueous solution. Photodetachment of phenoxide leads to wave packet dynamics of the phenoxyl radical along 12 different vibrational modes. Eight of the modes are totally symmetric and support structural rearrangement upon electron ejection. Comparison to a previous photodetachment study of phenoxide in the gas phase reveals the important role played by the solvent environment in driving ultrafast structural reorganization induced by ionizing radiation. This work provides insight into the ultrafast molecular dynamics that follow the interaction of ionizing radiation with molecules in aqueous solution. The interaction of biomolecules with ionizing radiation induces structural changes which are still largely unknown. The authors use femtosecond wave packet spectroscopy to observe ultrafast structural dynamics that follow the photodetachment of phenoxide in aqueous solution.
Collapse
|
38
|
Gold Nanoclusters: Bridging Gold Complexes and Plasmonic Nanoparticles in Photophysical Properties. NANOMATERIALS 2019; 9:nano9070933. [PMID: 31261666 PMCID: PMC6669669 DOI: 10.3390/nano9070933] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [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.
Collapse
|
39
|
Carbery WP, Pinto-Pacheco B, Buccella D, Turner DB. Resolving the Fluorescence Quenching Mechanism of an Oxazine Dye Using Ultrabroadband Two-Dimensional Electronic Spectroscopy. J Phys Chem A 2019; 123:5072-5080. [DOI: 10.1021/acs.jpca.9b03632] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Affiliation(s)
- William P. Carbery
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Brismar Pinto-Pacheco
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Daniela Buccella
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| | - Daniel B. Turner
- Department of Chemistry, New York University, 100 Washington Square East, New York, New York 10003, United States
| |
Collapse
|
40
|
|
41
|
Rather SR, Scholes GD. From Fundamental Theories to Quantum Coherences in Electron Transfer. J Am Chem Soc 2019; 141:708-722. [PMID: 30412671 DOI: 10.1021/jacs.8b09059] [Citation(s) in RCA: 71] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Photoinduced electron transfer (ET) is a cornerstone of energy transduction from light to chemistry. The past decade has seen tremendous advances in the possible role of quantum coherent effects in the light-initiated energy and ET processes in chemical, biological, and materials systems. The prevalence of such coherence effects holds a promise to increase the efficiency and robustness of transport even in the face of energetic or structural disorder. A primary motive of this Perspective is to work out how to think about "coherence" in ET reactions. We will discuss how the interplay of basic parameters governing ET reactions-like electronic coupling, interactions with the environment, and intramolecular high-frequency quantum vibrations-impact coherences. This includes revisiting the insights from the seminal work on the theory of ET and time-resolved measurements on coherent dynamics to explore the role of coherences in ET reactions. We conclude by suggesting that in addition to optical spectroscopies, validating the functional role of coherences would require simultaneous mapping of correlated electron motion and atomically resolved nuclear structure.
Collapse
Affiliation(s)
- Shahnawaz R. Rather
- Frick Chemistry Laboratory , Princeton University , Princeton , New Jersey 08544 , United States
| | - Gregory D Scholes
- Frick Chemistry Laboratory , Princeton University , Princeton , New Jersey 08544 , United States
| |
Collapse
|
42
|
Khosravi SD, Bishop MM, LaFountain AM, Turner DB, Gibson GN, Frank HA, Berrah N. Addition of a Carbonyl End Group Increases the Rate of Excited-State Decay in a Carotenoid via Conjugation Extension and Symmetry Breaking. J Phys Chem B 2018; 122:10872-10879. [PMID: 30387609 DOI: 10.1021/acs.jpcb.8b06732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Steady-state absorption, transient absorption, and transient grating spectroscopies were employed to elucidate the role of a conjugated carbonyl group in the photophysics of carotenoids. Spheroidenone and spheroidene have similar molecular structures and differ only in an additional carbonyl group in spheroidenone. Comparison of the optical responses of these two molecules under similar experimental conditions was used to understand the role of this carbonyl group in the structure. It was found that the carbonyl group has two main effects: first, it dramatically increases the depopulation rate of the excited states of the molecule. The lifetimes of all the excited states of spheroidenone were found to be almost half of the ones for spheroidene. Second, the presence of the carbonyl group in the chain alters the decay mechanism to the symmetry-forbidden S1 state of the molecule, so that the higher vibrational levels of the S1 state are populated much more effectively. It was also revealed that for both molecules, the S2/S x → S1(hot) → S1 decay process is not purely sequential and follows a branched model.
Collapse
Affiliation(s)
| | | | | | - Daniel B Turner
- Department of Chemistry , New York University , New York 10003 , United States
| | | | | | | |
Collapse
|
43
|
Jumper CC, Rafiq S, Wang S, Scholes GD. From coherent to vibronic light harvesting in photosynthesis. Curr Opin Chem Biol 2018; 47:39-46. [DOI: 10.1016/j.cbpa.2018.07.023] [Citation(s) in RCA: 36] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2018] [Accepted: 07/18/2018] [Indexed: 11/27/2022]
|
44
|
Brown AM, McCusker CE, Carey MC, Blanco-Rodríguez AM, Towrie M, Clark IP, Vlček A, McCusker JK. Vibrational Relaxation and Redistribution Dynamics in Ruthenium(II) Polypyridyl-Based Charge-Transfer Excited States: A Combined Ultrafast Electronic and Infrared Absorption Study. J Phys Chem A 2018; 122:7941-7953. [DOI: 10.1021/acs.jpca.8b06197] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Allison M. Brown
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Catherine E. McCusker
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Monica C. Carey
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Ana Maria Blanco-Rodríguez
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
| | - Michael Towrie
- Central Laser Facility, Research Complex at Harwell, STFC, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Ian P. Clark
- Central Laser Facility, Research Complex at Harwell, STFC, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Antonín Vlček
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
- J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-182 23 Prague, Czech Republic
| | - James K. McCusker
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| |
Collapse
|
45
|
Jumper CC, van Stokkum IHM, Mirkovic T, Scholes GD. Vibronic Wavepackets and Energy Transfer in Cryptophyte Light-Harvesting Complexes. J Phys Chem B 2018; 122:6328-6340. [PMID: 29847127 DOI: 10.1021/acs.jpcb.8b02629] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Determining the key features of high-efficiency photosynthetic energy transfer remains an ongoing task. Recently, there has been evidence for the role of vibronic coherence in linking donor and acceptor states to redistribute oscillator strength for enhanced energy transfer. To gain further insights into the interplay between vibronic wavepackets and energy-transfer dynamics, we systematically compare four structurally related phycobiliproteins from cryptophyte algae by broad-band pump-probe spectroscopy and extend a parametric model based on global analysis to include vibrational wavepacket characterization. The four phycobiliproteins isolated from cryptophyte algae are two "open" structures and two "closed" structures. The closed structures exhibit strong exciton coupling in the central dimer. The dominant energy-transfer pathway occurs on the subpicosecond timescale across the largest energy gap in each of the proteins, from central to peripheral chromophores. All proteins exhibit a strong 1585 cm-1 coherent oscillation whose relative amplitude, a measure of vibronic intensity borrowing from resonance between donor and acceptor states, scales with both energy-transfer rates and damping rates. Central exciton splitting may aid in bringing the vibronically linked donor and acceptor states into better resonance resulting in the observed doubled rate in the closed structures. Several excited-state vibrational wavepackets persist on timescales relevant to energy transfer, highlighting the importance of further investigation of the interplay between electronic coupling and nuclear degrees of freedom in studies on high-efficiency photosynthesis.
Collapse
Affiliation(s)
- Chanelle C Jumper
- Department of Chemistry , University of Toronto , 80 St. George Street , Toronto , Ontario M5S 3H6 , Canada.,Department of Chemistry , Princeton University , Washington Road , Princeton , New Jersey 08544 , United States
| | - Ivo H M van Stokkum
- LaserLaB, Department of Physics and Astronomy , Vrije Universiteit Amsterdam , De Boelelaan 1081 , 1081 HV Amsterdam , The Netherlands
| | - Tihana Mirkovic
- Department of Chemistry , University of Toronto , 80 St. George Street , Toronto , Ontario M5S 3H6 , Canada
| | - Gregory D Scholes
- Department of Chemistry , University of Toronto , 80 St. George Street , Toronto , Ontario M5S 3H6 , Canada.,Department of Chemistry , Princeton University , Washington Road , Princeton , New Jersey 08544 , United States
| |
Collapse
|
46
|
Maiuri M, Ostroumov EE, Saer RG, Blankenship RE, Scholes GD. Coherent wavepackets in the Fenna-Matthews-Olson complex are robust to excitonic-structure perturbations caused by mutagenesis. Nat Chem 2018; 10:177-183. [PMID: 29359758 DOI: 10.1038/nchem.2910] [Citation(s) in RCA: 81] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Accepted: 11/15/2017] [Indexed: 01/24/2023]
Abstract
Femtosecond pulsed excitation of light-harvesting complexes creates oscillatory features in their response. This phenomenon has inspired a large body of work aimed at uncovering the origin of the coherent beatings and possible implications for function. Here we exploit site-directed mutagenesis to change the excitonic level structure in Fenna-Matthews-Olson (FMO) complexes and compare the coherences using broadband pump-probe spectroscopy. Our experiments detect two oscillation frequencies with dephasing on a picosecond timescale-both at 77 K and at room temperature. By studying these coherences with selective excitation pump-probe experiments, where pump excitation is in resonance only with the lowest excitonic state, we show that the key contributions to these oscillations stem from ground-state vibrational wavepackets. These experiments explicitly show that the coherences-although in the ground electronic state-can be probed at the absorption resonances of other bacteriochlorophyll molecules because of delocalization of the electronic excitation over several chromophores.
Collapse
Affiliation(s)
- Margherita Maiuri
- Department of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08544, USA
| | - Evgeny E Ostroumov
- Department of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08544, USA
| | - Rafael G Saer
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri 63130, USA.,Photosynthetic Antenna Research Center, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Robert E Blankenship
- Department of Biology, Washington University in St. Louis, St. Louis, Missouri 63130, USA.,Photosynthetic Antenna Research Center, Washington University in St. Louis, St. Louis, Missouri 63130, USA.,Department of Chemistry, Washington University in St. Louis, St. Louis, Missouri 63130, USA
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08544, USA
| |
Collapse
|
47
|
Zhou M, Zeng C, Song Y, Padelford JW, Wang G, Sfeir MY, Higaki T, Jin R. On the Non‐Metallicity of 2.2 nm Au
246
(SR)
80
Nanoclusters. Angew Chem Int Ed Engl 2017; 56:16257-16261. [DOI: 10.1002/anie.201709095] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Meng Zhou
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| | - Chenjie Zeng
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| | - Yongbo Song
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| | | | - Gangli Wang
- Department of Chemistry Georgia State University Atlanta GA 30302 USA
| | - Matthew Y. Sfeir
- Center for Functional Nanomaterials Brookhaven National Laboratory Upton NY 11973 USA
| | - Tatsuya Higaki
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| | - Rongchao Jin
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| |
Collapse
|
48
|
Zhou M, Zeng C, Song Y, Padelford JW, Wang G, Sfeir MY, Higaki T, Jin R. On the Non‐Metallicity of 2.2 nm Au
246
(SR)
80
Nanoclusters. Angew Chem Int Ed Engl 2017. [DOI: 10.1002/ange.201709095] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Affiliation(s)
- Meng Zhou
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| | - Chenjie Zeng
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| | - Yongbo Song
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| | | | - Gangli Wang
- Department of Chemistry Georgia State University Atlanta GA 30302 USA
| | - Matthew Y. Sfeir
- Center for Functional Nanomaterials Brookhaven National Laboratory Upton NY 11973 USA
| | - Tatsuya Higaki
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| | - Rongchao Jin
- Department of Chemistry Carnegie Mellon University Pittsburgh PA 15213 USA
| |
Collapse
|
49
|
Vibronically coherent ultrafast triplet-pair formation and subsequent thermally activated dissociation control efficient endothermic singlet fission. Nat Chem 2017; 9:1205-1212. [PMID: 29168494 DOI: 10.1038/nchem.2856] [Citation(s) in RCA: 125] [Impact Index Per Article: 17.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2016] [Accepted: 07/28/2017] [Indexed: 12/20/2022]
Abstract
Singlet exciton fission (SF), the conversion of one spin-singlet exciton (S1) into two spin-triplet excitons (T1), could provide a means to overcome the Shockley-Queisser limit in photovoltaics. SF as measured by the decay of S1 has been shown to occur efficiently and independently of temperature, even when the energy of S1 is as much as 200 meV less than that of 2T1. Here we study films of triisopropylsilyltetracene using transient optical spectroscopy and show that the triplet pair state (TT), which has been proposed to mediate singlet fission, forms on ultrafast timescales (in 300 fs) and that its formation is mediated by the strong coupling of electronic and vibrational degrees of freedom. This is followed by a slower loss of singlet character as the excitation evolves to become only TT. We observe the TT to be thermally dissociated on 10-100 ns timescales to form free triplets. This provides a model for 'temperature-independent' efficient TT formation and thermally activated TT separation.
Collapse
|
50
|
|