1
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Xu W, Wei L, Wang Z, Zhu R, Jiang J, Liu H, Du J, Weng TC, Zhang YB, Huang Y, Liu W. Tracking Ultrafast Fluorescence Switch-On and Color-Tuned Dynamics in Acceptor-Donor-Acceptor Chromophore. J Phys Chem B 2021; 125:10796-10804. [PMID: 34524821 DOI: 10.1021/acs.jpcb.1c05936] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Understanding how the conformational change of conjugated molecules with acceptor-donor-acceptor (A-D-A) architecture affects their physical and optoelectronic properties is critical for determining their ultimate performance in organic electronic devices. Here, we utilized femtosecond transient absorption, time-resolved upconversion photoluminescence spectroscopy, and tunable femtosecond-stimulated Raman spectroscopy, aided by quantum chemical calculations, to systematically investigate the excited state structural dynamics of the intramolecular charge transfer of the tetramethoxy anthracene-based fluorophore 2,3,6,7-tetramethoxy 9,10-dibenzaldehydeanthracene (AnDA) and its derivative 2,3,6,7-tetramethoxy 9,10-diphenylanthracene (TMDPAn) in chloroform. In the AnDA molecule, the tetramethoxy anthracene and benzaldehyde moieties exhibit a strong ability to donate and withdraw electrons. Upon photoexcitation, AnDA shows intriguing ultrafast fluorescence switch-on and red shift dynamics on charge transfer states, and the temporal evolution of AnDA recorded by ultrafast spectroscopy reveals a dynamic picture of two-step intramolecular charge transfer assisted by ultrafast conformational changes and solvation processes. Removing the aldehyde group from TMDPAn significantly decreases the electron pulling capacity of the phenyl unit and disables charge transfer characteristics.
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Affiliation(s)
- Wenqi Xu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China.,STU and SIOM Joint Laboratory for Superintense Lasers and the Applications, Shanghai 201210, People's Republic of China
| | - Lei Wei
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China
| | - Zhengxin Wang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China.,STU and SIOM Joint Laboratory for Superintense Lasers and the Applications, Shanghai 201210, People's Republic of China
| | - Ruixue Zhu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China
| | - Jiaming Jiang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China
| | - Huiyan Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China
| | - Juan Du
- State Key Laboratory of High Field Laser Physics, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
| | - Tsu-Chien Weng
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China
| | - Yue-Biao Zhang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China
| | - Yifan Huang
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China
| | - Weimin Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, People's Republic of China.,STU and SIOM Joint Laboratory for Superintense Lasers and the Applications, Shanghai 201210, People's Republic of China
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2
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Kang S, Kim T, Hong Y, Würthner F, Kim D. Charge-Delocalized State and Coherent Vibrational Dynamics in Rigid PBI H-Aggregates. J Am Chem Soc 2021; 143:9825-9833. [PMID: 34165972 DOI: 10.1021/jacs.1c03276] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Herein, the ultrafast photoinduced dynamics and vibrational coherences for two perylenebisimide (PBI) H-aggregates showcase the formation of the excimer state and the delocalized radical anion state in the excited state, respectively. Using femtosecond transient absorption (fs-TA) and time-resolved impulsive stimulated Raman scattering (TR-ISRS) measurements, we unveiled excited-state dynamics of PBI H-aggregates in two aspects: (1) the intermolecular interactions between PBI units in H-aggregates induce the formation of new excited states, excimer and delocalized radical anion states, and (2) the intermolecular out-of-plane along the aggregate axis and the PBI core C═C stretch Raman modes can be a crucial indicator to understand the coherent exciton dynamics in H-aggregates. Notably, those excited-state Raman modes showed stationary peak positions during the excited-state dynamics. TR-ISRS analysis provides insights into the excited-state vibrational coherences concerning the formation of the excimer and charge-delocalized state in each aggregate system.
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Affiliation(s)
- Seongsoo Kang
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, South Korea
| | - Taeyeon Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, South Korea
| | - Yongseok Hong
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, South Korea
| | - Frank Würthner
- Institut for Organische Chemie and Center for Nanosystems Chemistry, Universität Würzburg, Am Hubland, 97074 Würzburg, Germany
| | - Dongho Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 03722, South Korea
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3
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Muthike AK, Carlotti B, Madu IK, Jiang H, Kim H, Wu Q, Yu L, Zimmerman PM, Goodson T. The Role of the Core Attachment Positioning in Triggering Intramolecular Singlet Exciton Fission in Perylene Diimide Tetramers. J Phys Chem B 2021; 125:5114-5131. [PMID: 33961426 DOI: 10.1021/acs.jpcb.1c02534] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Previous studies have proposed that the presence of a flexible π-bridge linker is crucial in activating intramolecular singlet exciton fission (iSEF) in multichromophoric systems. In this study, we report the photophysical properties of three analogous perylene diimide (PDI) dendritic tetramers showing flexible/twisted π-bridged structures with α- and β-substitutions and a rigid/planar structure with a β-fused ring (βC) connection to a benzodithiophene-thiophene (BDT-Th) core. The rigidity and enhanced planarity of βC lead to significant intramolecular charge transfer and triplet formation via an intersystem crossing pathway. Steady-state spectroscopic measurements reveal similar absorption and emission spectra for the α-tetramer and the parent PDI monomer. However, their fluorescence quantum yield is significantly different. The negligible fluorescence yield of the α-tetramer (0.04%) is associated with a competitive nonradiative decay pathway. Indeed, for this twisted compound in a high polar environment, a fast and efficient iSEF with a triplet quantum yield of 124% is observed. Our results show that the α-single-bond connections in the α compound are capable of interrupting the coupling among the PDI units, favoring iSEF. We propose that the formation of the double triplet (1[TT]) state is through a superposition of singlet states known as [S1S0][TT]CT, which has been suggested previously for pentacene derivatives. Using steady-state and time-resolved spectroscopic experiments, we demonstrate that the conformational flexibility of the linker itself is necessary but not sufficient to allow iSEF. For the case of the other twisted tetramer, β, the strong π-π co-facial interactions between the adjacent PDI units in its structure lead to excimer formation. These excimer states trap the singlet excitons preventing the formation of the 1[TT] state, thus inhibiting iSEF.
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Affiliation(s)
- Angelar K Muthike
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Benedetta Carlotti
- Department of Chemistry Biology and Biotechnology, University of Perugia, via Elce di Sotto n.8, 06123 Perugia, Italy
| | - Ifeanyi K Madu
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Hanjie Jiang
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Hyungjun Kim
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States.,Department of Chemistry, Incheon National University, Incheon 22012, Republic of Korea
| | - Qinghe Wu
- Department of Chemistry and The James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
| | - Luping Yu
- Department of Chemistry and The James Franck Institute, The University of Chicago, Chicago, Illinois 60637, United States
| | - Paul M Zimmerman
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Theodore Goodson
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, United States
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4
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Sarkar R, Kar M, Habib M, Zhou G, Frauenheim T, Sarkar P, Pal S, Prezhdo OV. Common Defects Accelerate Charge Separation and Reduce Recombination in CNT/Molecule Composites: Atomistic Quantum Dynamics. J Am Chem Soc 2021; 143:6649-6656. [PMID: 33896175 DOI: 10.1021/jacs.1c02325] [Citation(s) in RCA: 27] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Carbon nanotubes (CNTs) are appealing candidates for solar and optoelectronic applications. Traditionally used as electron sinks, CNTs can also perform as electron donors, as exemplified by coupling with perylenediimide (PDI). To achieve high efficiencies, electron transfer (ET) should be fast, while subsequent charge recombination should be slow. Typically, defects are considered detrimental to material performance because they accelerate charge and energy losses. We demonstrate that, surprisingly, common CNT defects improve rather than deteriorate the performance. CNTs and other low dimensional materials accommodate moderate defects without creating deep traps. At the same time, charge redistribution caused by CNT defects creates an additional electrostatic potential that increases the CNT work function and lowers CNT energy levels relative to those of the acceptor species. Hence, the energy gap for the ET is decreased, while the gap for the charge recombination is increased. The effect is particularly important because charge acceptors tend to bind near defects due to enhanced chemical interactions. The time-domain simulation of the excited-state dynamics provides an atomistic picture of the observed phenomenon and characterizes in detail the electronic states, vibrational motions, inelastic and elastic electron-phonon interactions, and time scales of the charge separation and recombination processes. The findings should apply generally to low-dimensional materials, because they dissipate defect strain better than bulk semiconductors. Our calculations reveal that CNT performance is robust to common defects and that moderate defects are essential rather than detrimental for CNT application in energy, electronics, and related fields.
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Affiliation(s)
- Ritabrata Sarkar
- Department of Chemistry, University of Gour Banga, Malda 732103, India
| | - Moumita Kar
- Department of Chemistry, Visva-Bharati University, Santiniketan 731235, India
| | - Md Habib
- Department of Chemistry, University of Gour Banga, Malda 732103, India
| | - Guoqing Zhou
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California 90089, United States
| | - Thomas Frauenheim
- Bremen Center for Computational Materials Science, University of Bremen, Bremen 28359, Germany.,Shenzhen JL Computational Science and Applied Research Institute (CSAR), Shenzhen 518110, China.,Beijing Computational Science Research Center (CSRC), Beijing 100193, China
| | - Pranab Sarkar
- Department of Chemistry, Visva-Bharati University, Santiniketan 731235, India
| | - Sougata Pal
- Department of Chemistry, University of Gour Banga, Malda 732103, India
| | - Oleg V Prezhdo
- Department of Chemistry, University of Southern California, Los Angeles, California 90089, United States
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5
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Zhang W, Xu W, Zhang G, Kong J, Niu X, Chan JMW, Liu W, Xia A. Direct Tracking Excited-State Intramolecular Charge Redistribution of Acceptor-Donor-Acceptor Molecule by Means of Femtosecond Stimulated Raman Spectroscopy. J Phys Chem B 2021; 125:4456-4464. [PMID: 33902280 DOI: 10.1021/acs.jpcb.1c01742] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Symmetric quadrupolar molecules generally exhibit apolar ground states and dipolar excited states in a polar environment, which is explained by the excited state evolution from initial charge delocalization over all molecules to localization on one branch of the molecules after a femtosecond pulse excitation. However, direct observation of excited-state charge redistribution (delocalization/localization) is hardly accessible. Here, the intramolecular charge delocalization/localization character of a newly synthesized acceptor-donor-acceptor molecule (ADA) has been intensively investigated by femtosecond stimulated Raman scattering (FSRS) together with femtosecond transient absorption (fs-TA) spectroscopy. By tracking the excited state Raman spectra of the specific alkynyl (-C≡C-) bonds at each branch of ADA, we found that the nature of the relaxed S1 state is strongly governed by solvent polarity: symmetric delocalized intramolecular charge transfer (ICT) characters occurred in apolar solvent, whereas the asymmetric localized ICT characters appeared in polar solvent because of solvation. The solvation dynamics of ADA extracted from fs-TA is consistent with the time constants obtained by FSRS, but the FSRS clearly tracks the excited state intramolecular charge transfer delocalization/localization.
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Affiliation(s)
- Wei Zhang
- School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China.,Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R China.,University of Chinese Academy of Sciences, Beijing 100049, P. R China
| | - Wenqi Xu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, P. R. China.,STU & SIOM Joint Laboratory for Superintense Lasers and the Applications, Shanghai 201210, P. R. China
| | - Guoxian Zhang
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Pvt., Ottawa, Ontario K1N 6N5, Canada
| | - Jie Kong
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R China.,University of Chinese Academy of Sciences, Beijing 100049, P. R China
| | - Xinmiao Niu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R China.,University of Chinese Academy of Sciences, Beijing 100049, P. R China
| | - Julian M W Chan
- Department of Chemistry and Biomolecular Sciences, University of Ottawa, 10 Marie Curie Pvt., Ottawa, Ontario K1N 6N5, Canada
| | - Weimin Liu
- School of Physical Science and Technology, ShanghaiTech University, Shanghai 201210, P. R. China.,STU & SIOM Joint Laboratory for Superintense Lasers and the Applications, Shanghai 201210, P. R. China
| | - Andong Xia
- School of Science, Beijing University of Posts and Telecommunications (BUPT), Beijing 100876, P. R. China.,Beijing National Laboratory for Molecular Sciences (BNLMS), Key Laboratory of Photochemistry, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R China
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6
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Schultz JD, Shin JY, Chen M, O'Connor JP, Young RM, Ratner MA, Wasielewski MR. Influence of Vibronic Coupling on Ultrafast Singlet Fission in a Linear Terrylenediimide Dimer. J Am Chem Soc 2021; 143:2049-2058. [PMID: 33464054 DOI: 10.1021/jacs.0c12201] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Singlet fission (SF) is a photophysical process capable of boosting the efficiency of solar cells. Recent experimental investigations into the mechanism of SF provide evidence for coherent mixing between the singlet, triplet, and charge transfer basis states. Up until now, this interpretation has largely focused on electronic interactions; however, nuclear motions resulting in vibronic coupling have been suggested to support rapid and efficient SF in organic chromophore assemblies. Further information about the complex interactions between vibronic excited states is needed to understand the potential role of this coupling in SF. Here, we report mixed singlet and correlated triplet pair states giving rise to sub-50 fs SF in a terrylene-3,4:11,12-bis(dicarboximide) (TDI) dimer in which the two TDI molecules are covalently linked by a direct N-N connection at one of their imide positions, leading to a linear dimer with perpendicular TDI π systems. We observe the transfer of low-frequency coherent wavepackets between the initial predominantly singlet states to the product triplet-dominated states. This implies a non-negligible dependence of SF on nonadiabatic coupling in this dimer. We interpret our experimental results in the framework of a modified Holstein Hamiltonian, which predicts that vibronic interactions between low-frequency singlet modes and high-frequency correlated triplet pair motions lead to mixing of the pure basis states. These results highlight how nonadiabatic mixing can shape the complex potential energy landscape underlying ultrafast SF.
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Affiliation(s)
- Jonathan D Schultz
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Jae Yoon Shin
- Department of Advanced Materials Chemistry, Korea University, 30019 Sejong-ro, Sejong, South Korea
| | - Michelle Chen
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - James P O'Connor
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M Young
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Mark A Ratner
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
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7
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van Stokkum IHM, Jumper CC, Lee TS, Myahkostupov M, Castellano FN, Scholes GD. Vibronic and excitonic dynamics in perylenediimide dimers and tetramer. J Chem Phys 2020; 153:224101. [PMID: 33317279 DOI: 10.1063/5.0024530] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Broad-band pump-probe spectroscopy combined with global and target analysis is employed to study the vibronic and excitonic dynamics of two dimers and a tetramer of perylenediimides. A simultaneous analysis is developed for two systems that have been measured in the same conditions. This enhances the resolvability of the vibronic and excitonic dynamics of the systems, and the solvent contributions that are common in the experiments. We resolve two oscillations of 1399 cm-1 or 311 cm-1 damped with ≈30/ps involved in vibrational relaxation and two more oscillations of 537 cm-1 or 136 cm-1 damped with ≈3/ps. A relaxation process with a rate of 2.1/ps-3.2/ps that is positively correlated with the excitonic coupling was discovered in all three model systems, attributed to annihilation of the one but lowest exciton state.
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Affiliation(s)
- Ivo H M van Stokkum
- Institute for Lasers, Life and Biophotonics, Faculty of Sciences, Vrije Universiteit Amsterdam, De Boelelaan 1081, 1081 HV Amsterdam, The Netherlands
| | - Chanelle C Jumper
- Department of Chemical and Biological Engineering, Princeton University, Princeton, New Jersey 08544, USA
| | - Tia S Lee
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | - Mykhaylo Myahkostupov
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | - Felix N Castellano
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, USA
| | - Gregory D Scholes
- Department of Chemistry, Princeton University, Princeton, New Jersey 08544, USA
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8
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Twisted Intramolecular Charge Transfer State of a "Push-Pull" Emitter. Int J Mol Sci 2020; 21:ijms21217999. [PMID: 33121185 PMCID: PMC7662227 DOI: 10.3390/ijms21217999] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 10/26/2020] [Accepted: 10/26/2020] [Indexed: 11/17/2022] Open
Abstract
The excited state Raman spectra of 4-dicyanomethylene-2-methyl-6-(p-dimethylaminostyryl)-4H-pyran (DCM) in the locally-excited (LE) and the intramolecular charge transfer (ICT) states have been separately measured by time-resolved stimulated Raman spectroscopy. In a polar dimethylsulfoxide solution, the ultrafast ICT of DCM with a time constant of 1.0 ps was observed in addition to the vibrational relaxation in the ICT state of 4–7 ps. On the other hand, the energy of the ICT state of DCM becomes higher than that of the LE state in a less polar chloroform solution, where the initially-photoexcited ICT state with the LE state shows the ultrafast internal conversion to the LE state with a time constant of 300 fs. The excited-state Raman spectra of the LE and ICT state of DCM showed several major vibrational modes of DCM in the LE and ICT conformer states coexisting in the excited state. Comparing to the time-dependent density functional theory simulations and the experimental results of similar push-pull type molecules, a twisted geometry of the dimethylamino group is suggested for the structure of DCM in the S1/ICT state.
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9
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Carlotti B, Madu IK, Kim H, Cai Z, Jiang H, Muthike AK, Yu L, Zimmerman PM, Goodson T. Activating intramolecular singlet exciton fission by altering π-bridge flexibility in perylene diimide trimers for organic solar cells. Chem Sci 2020; 11:8757-8770. [PMID: 34123128 PMCID: PMC8163386 DOI: 10.1039/d0sc03271a] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Accepted: 08/06/2020] [Indexed: 01/01/2023] Open
Abstract
In this study, two analogous perylene diimide (PDI) trimers, whose structures show rotatable single bond π-bridge connection (twisted) vs. rigid/fused π-bridge connection (planar), were synthesized and investigated. We show via time resolved spectroscopic measurements how the π-bridge connections in A-π-D-π-A-π-D-π-A multichromophoric PDI systems strongly affect the triplet yield and triplet formation rate. In the planar compound, with stronger intramolecular charge transfer (ICT) character, triplet formation occurs via conventional intersystem crossing. However, clear evidence of efficient and fast intramolecular singlet exciton fission (iSEF) is observed in the twisted trimer compound with weaker ICT character. Multiexciton triplet generation and separation occur in the twisted (flexible-bridged) PDI trimer, where weak coupling among the units is observed as a result of the degenerate double triplet and quintet states, obtained by quantum chemical calculations. The high triplet yield and fast iSEF observed in the twisted compound are due not only to enthalpic viability but also to the significant entropic gain allowed by its trimeric structure. Our results represent a significant step forward in structure-property understanding, and may direct the design of new efficient iSEF materials.
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Affiliation(s)
- Benedetta Carlotti
- Department of Chemistry, University of Michigan Ann Arbor MI 48109 USA
- Department of Chemistry Biology and Biotechnology, University of Perugia via Elce di Sotto n.8 06123 Perugia Italy
| | - Ifeanyi K Madu
- Department of Chemistry, University of Michigan Ann Arbor MI 48109 USA
| | - Hyungjun Kim
- Department of Chemistry, University of Michigan Ann Arbor MI 48109 USA
- Department of Chemistry, Incheon National University Incheon 22012 Republic of Korea
| | - Zhengxu Cai
- Department of Chemistry, The James Franck Institute, The University of Chicago 929 East 57th Street Chicago IL 60637 USA
| | - Hanjie Jiang
- Department of Chemistry, University of Michigan Ann Arbor MI 48109 USA
| | - Angelar K Muthike
- Department of Chemistry, University of Michigan Ann Arbor MI 48109 USA
| | - Luping Yu
- Department of Chemistry, The James Franck Institute, The University of Chicago 929 East 57th Street Chicago IL 60637 USA
| | - Paul M Zimmerman
- Department of Chemistry, University of Michigan Ann Arbor MI 48109 USA
| | - Theodore Goodson
- Department of Chemistry, University of Michigan Ann Arbor MI 48109 USA
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10
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Harmer R, Fan H, Lloyd K, Doble S, Avenoso J, Yan H, Rego LGC, Gundlach L, Galoppini E. Synthesis and Properties of Perylene-Bridge-Anchor Chromophoric Compounds. J Phys Chem A 2020; 124:6330-6343. [PMID: 32654486 DOI: 10.1021/acs.jpca.0c04609] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The quest to control chromophore/semiconductor properties to enable new technologies in energy and information science requires detailed understanding of charge carrier dynamics at the atomistic level, which can often be attained through the use of model systems. Perylene-bridge-anchor compounds are successful models for studying fundamental charge transfer processes on TiO2, which remains among the most commonly investigated and technologically important interfaces, mostly because of perylene's advantageous electronic and optical properties. Nonetheless, the ability to fully exploit synthetically the substitution pattern of perylene with linker (= bridge-anchor) units remains little explored. Here we developed 2,5-di-tert-butylperylene (DtBuPe)-bridge-anchor compounds with t-Bu group substituents to prevent π-stacking and one or two linker units in both the peri and ortho positions, by employing a combination of Friedel-Crafts alkylations, bromination, iridium-catalyzed borylation, and palladium-catalyzed cross-coupling reactions. Photophysical characterization and computational analysis by density functional theory (DFT) and time-dependent DFT (TD-DFT) were carried out on four DtBuPe acrylic acid derivatives with a single or a double linker in peri (12b), ortho (15b), peri,peri (18b), and ortho,ortho (21b). The energies of the unoccupied orbitals {LUMO, LUMO + 1, LUMO + 2} are strongly affected by the presence of a π-conjugated linker, resulting in a stabilization of these states and a red shift of their absorption and emission spectra, as well as the loss of vibronic structure in the spectrum of the peri,peri compound, consistent with the strong bonding character of this substitution pattern.
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Affiliation(s)
- Ryan Harmer
- Department of Chemistry, Rutgers University, Newark, New Jersey 07102, United States
| | - Hao Fan
- Department of Chemistry, Rutgers University, Newark, New Jersey 07102, United States
| | - Katherine Lloyd
- Department of Chemistry, Rutgers University, Newark, New Jersey 07102, United States
| | - Samantha Doble
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Joseph Avenoso
- Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, United States
| | - Han Yan
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States
| | - Luis G C Rego
- Department of Physics, Universidade Federal de Santa Catarina (UFSC), Florianopolis, South Carolina 88040-900, Brazil
| | - Lars Gundlach
- Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, United States.,Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716, United States
| | - Elena Galoppini
- Department of Chemistry, Rutgers University, Newark, New Jersey 07102, United States
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11
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Kwang SY, Frontiera RR. Spatially Offset Femtosecond Stimulated Raman Spectroscopy: Observing Exciton Transport through a Vibrational Lens. J Phys Chem Lett 2020; 11:4337-4344. [PMID: 32427490 DOI: 10.1021/acs.jpclett.0c01114] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
To design better molecular electronic devices, we need a strong understanding of how charges or excitons propagate, as many efficiency losses arise during transport. Exciton transport has been difficult to study because excitons tend to be short-lived, have short diffusion lengths, and can easily recombine. Here, we debut spatially offset femtosecond stimulated Raman spectroscopy (SO-FSRS), a three-pulse ultrafast microscopy technique. By offsetting the photoexcitation beam, we can monitor Raman spectral changes as a function of both time and position. We used SO-FSRS on 6,13-bis(triisopropylsilylethynyl) pentacene, a well-studied organic semiconductor used in photovoltaics and field-effect transistors. We demonstrated that the fast exciton and free charge carrier transport axes are identical and observed that exciton transport is less anisotropic by a factor of ∼3. SO-FSRS is the first technique that directly tracks molecular structural evolution during exciton transport, which can provide roadmaps for tailor-making molecules for specific electronic devices.
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Affiliation(s)
- Siu Yi Kwang
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
| | - Renee R Frontiera
- Department of Chemistry, University of Minnesota, Minneapolis, Minnesota 55455, United States
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12
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Kim W, Kim T, Kang S, Hong Y, Würthner F, Kim D. Tracking Structural Evolution during Symmetry‐Breaking Charge Separation in Quadrupolar Perylene Bisimide with Time‐Resolved Impulsive Stimulated Raman Spectroscopy. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202002733] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Woojae Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Taeyeon Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Seongsoo Kang
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Yongseok Hong
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Frank Würthner
- Institut für Organische Chemie & Center for, Nanosystems Chemistry Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Dongho Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
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13
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Kim W, Kim T, Kang S, Hong Y, Würthner F, Kim D. Tracking Structural Evolution during Symmetry‐Breaking Charge Separation in Quadrupolar Perylene Bisimide with Time‐Resolved Impulsive Stimulated Raman Spectroscopy. Angew Chem Int Ed Engl 2020; 59:8571-8578. [DOI: 10.1002/anie.202002733] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2020] [Indexed: 01/12/2023]
Affiliation(s)
- Woojae Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Taeyeon Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Seongsoo Kang
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Yongseok Hong
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
| | - Frank Würthner
- Institut für Organische Chemie & Center for, Nanosystems Chemistry Universität Würzburg Am Hubland 97074 Würzburg Germany
| | - Dongho Kim
- Department of Chemistry Spectroscopy Laboratory for Functional π-Electronic Systems Yonsei University 03722 Seoul Korea
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14
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Kim J, Yoon TH, Cho M. Time-Resolved Impulsive Stimulated Raman Spectroscopy with Synchronized Triple Mode-Locked Lasers. J Phys Chem Lett 2020; 11:2864-2869. [PMID: 32212699 DOI: 10.1021/acs.jpclett.0c00596] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
A complete understanding of a photochemical reaction dynamics begins with real-time measurements of both electronic and vibrational structures of photoexcited molecules. Time-resolved impulsive stimulated Raman spectroscopy (TR-ISRS) with femtosecond actinic pump, Raman pump, and Raman probe pulses is one of the incisive techniques enabling one to investigate the structural changes of photoexcited molecules. Herein, we demonstrate that such femtosecond TR-ISRS is feasible with synchronized triple mode-locked lasers without using any time-delay devices. Taking advantage of precise control of the three repetition rates independently, we could achieve automatic scanning of two delay times between the three pulses, which makes both rapid data acquisition and wide dynamic range measurement of the fifth-order TR-ISRS signal achievable. We thus anticipate that the present triple mode-locked laser-based TR-ISRS technique will be of critical use for long-term monitoring of photochemical reaction dynamics in condensed phases and biological systems.
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Affiliation(s)
- JunWoo Kim
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul 02841, Republic of Korea
| | - Tai Hyun Yoon
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul 02841, Republic of Korea
- Department of Physics, Korea University, Seoul 02841, Republic of Korea
| | - Minhaeng Cho
- Center for Molecular Spectroscopy and Dynamics, Institute for Basic Science (IBS), Seoul 02841, Republic of Korea
- Department of Chemistry, Korea University, Seoul 02841, Republic of Korea
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15
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Pižl M, Picchiotti A, Rebarz M, Lenngren N, Yingliang L, Záliš S, Kloz M, Vlček A. Time-Resolved Femtosecond Stimulated Raman Spectra and DFT Anharmonic Vibrational Analysis of an Electronically Excited Rhenium Photosensitizer. J Phys Chem A 2020; 124:1253-1265. [PMID: 31971382 DOI: 10.1021/acs.jpca.9b10840] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Time-resolved femtosecond stimulated Raman spectra (FSRS) of a prototypical organometallic photosensitizer/photocatalyst ReCl(CO)3(2,2'-bipyridine) were measured in a broad spectral range ∼40-2000 (4000) cm-1 at time delays from 40 fs to 4 ns after 400 nm excitation of the lowest allowed electronic transition. Theoretical ground- and excited-state Raman spectra were obtained by anharmonic vibrational analysis using second-order vibrational perturbation theory on vibrations calculated by harmonic approximation at density functional theory-optimized structures. A good match with anharmonically calculated vibrational frequencies allowed for assigning experimental Raman features to particular vibrations. Observed frequency shifts upon excitation (ν(ReCl) and ν(CC inter-ring) vibrations upward; ν(CC, CN) and ν(Re-C) downward) are consistent with the bonding/antibonding characters of the highest occupied molecular orbital and the lowest unoccupied molecular orbital involved in excitation and support the delocalized formulation of the lowest triplet state as ReCl(CO)3 → bpy charge transfer. FSRS spectra show a mode-specific temporal evolution, providing insights into the intersystem crossing (ISC) mechanism and subsequent relaxation. Most of the Raman features are present at ∼40 fs and exhibit small shifts and intensity changes with time. The 1450-1600 cm-1 group of bands due to CC, CN, and CC(inter-ring) stretching vibrations undergoes extensive restructuring between 40 and ∼150 fs, followed by frequency upshifts and a biexponential (0.38, 21 ps) area growth, indicating progressing charge separation in the course of the formation and relaxation of the lowest triplet state. Early (40-150 fs) restructuring was also observed in the low-frequency range for ν(Re-Cl) and δ(Re-C-O) vibrations that are presumably activated by ISC. FSRS experimental innovations employed to measure low- and high-energy Raman features simultaneously are described and discussed in detail.
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Affiliation(s)
- Martin Pižl
- J. Heyrovský Institute of Physical Chemistry , Czech Academy of Sciences , Dolejškova 3 , 182 23 Prague , Czech Republic.,Department of Inorganic Chemistry , University of Chemistry and Technology, Prague , Technická 5 , CZ-166 28 Prague , Czech Republic
| | - Alessandra Picchiotti
- ELI Beamlines, Institute of Physics , Czech Academy of Sciences , Na Slovance 1999/2 , 182 00 Prague , Czech Republic
| | - Mateusz Rebarz
- ELI Beamlines, Institute of Physics , Czech Academy of Sciences , Na Slovance 1999/2 , 182 00 Prague , Czech Republic
| | - Nils Lenngren
- ELI Beamlines, Institute of Physics , Czech Academy of Sciences , Na Slovance 1999/2 , 182 00 Prague , Czech Republic
| | - Liu Yingliang
- Institute of Biotechnology , Czech Academy of Sciences , Průmyslová 595 , 252 50 Vestec , Czech Republic
| | - Stanislav Záliš
- J. Heyrovský Institute of Physical Chemistry , Czech Academy of Sciences , Dolejškova 3 , 182 23 Prague , Czech Republic
| | - Miroslav Kloz
- ELI Beamlines, Institute of Physics , Czech Academy of Sciences , Na Slovance 1999/2 , 182 00 Prague , Czech Republic
| | - Antonín Vlček
- J. Heyrovský Institute of Physical Chemistry , Czech Academy of Sciences , Dolejškova 3 , 182 23 Prague , Czech Republic.,School of Biological and Chemical Sciences , Queen Mary University of London , Mile End Road , London E1 4NS , U.K
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16
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Kamei T, Nishino S, Yagi A, Segawa Y, Shimada T. Ni-Catalyzed α-Selective C–H Borylations of Naphthalene-Based Aromatic Compounds. J Org Chem 2019; 84:14354-14359. [DOI: 10.1021/acs.joc.9b02333] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Toshiyuki Kamei
- Department of Chemical Engineering, National Institute of Technology, Nara College, Yamatokoriyama, Nara, 639-1080, Japan
| | - Soshi Nishino
- Department of Chemical Engineering, National Institute of Technology, Nara College, Yamatokoriyama, Nara, 639-1080, Japan
| | - Akiko Yagi
- Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan
| | - Yasutomo Segawa
- Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan
- JST, ERATO, Itami Molecular Nanocarbon Project, Chikusa, Nagoya 464-8602, Japan
| | - Toyoshi Shimada
- Department of Chemical Engineering, National Institute of Technology, Nara College, Yamatokoriyama, Nara, 639-1080, Japan
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17
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Mandal A, Schultz JD, Wu YL, Coleman AF, Young RM, Wasielewski MR. Transient Two-Dimensional Electronic Spectroscopy: Coherent Dynamics at Arbitrary Times along the Reaction Coordinate. J Phys Chem Lett 2019; 10:3509-3515. [PMID: 31188611 DOI: 10.1021/acs.jpclett.9b00826] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Recent advances in two-dimensional electronic spectroscopy (2DES) have enabled identification of fragile quantum coherences in condensed-phase systems near the equilibrium molecular geometry. In general, traditional 2DES cannot measure such coherences associated with photophysical processes that occur at times significantly after the initially prepared state has dephased, such as the evolution of the initial excited state into a charge transfer state. We demonstrate the use of transient two-dimensional electronic spectroscopy (t-2DES) to probe coherences in an electron donor-acceptor dyad consisting of a perylenediimide (PDI) acceptor and a perylene (Per) donor. An actinic pump pulse prepares the lowest excited singlet state of PDI followed by formation of the PDI•--Per•+ ion pair, which is probed at different times following the actinic pulse using 2DES. Analysis of the observed coherences provides information about electronic, vibronic, and vibrational interactions at any time along the reaction coordinate for ion pair formation.
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Affiliation(s)
- Aritra Mandal
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208-3113 , United States
| | - Jonathan D Schultz
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208-3113 , United States
| | - Yi-Lin Wu
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208-3113 , United States
| | - Adam F Coleman
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208-3113 , United States
| | - Ryan M Young
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208-3113 , United States
| | - Michael R Wasielewski
- Department of Chemistry and Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208-3113 , United States
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18
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Ma J, Zhang X, Phillips DL. Time-Resolved Spectroscopic Observation and Characterization of Water-Assisted Photoredox Reactions of Selected Aromatic Carbonyl Compounds. Acc Chem Res 2019; 52:726-737. [PMID: 30742408 DOI: 10.1021/acs.accounts.8b00619] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
In recent years, unusual and efficient self-photoredox reactions were detected for selected benzophenone derivatives (BPs) and anthraquinone derivatives (AQs) in aqueous environments by Wan and co-workers, where the carbonyl undergoes reduction to the corresponding alcohol and a side-chain alcohol group undergoes oxidation to the corresponding carbonyl. To unravel the photoredox reaction mechanisms of these types of BPs and AQs in aqueous environments, we have utilized a combination of time-resolved spectroscopy techniques such as femtosecond transient absorption, nanosecond transient absorption, and nanosecond time-resolved resonance Raman spectroscopy to detect and characterize the electronic absorption and vibrational spectra of the intermediates and transient species from the femtosecond to microsecond time region after they are generated in the photoredox reactions. With the assistance of density functional theory calculations to simulate the electronic absorption and Raman spectra, the structural and kinetic information on the key reactive intermediates is described. Furthermore, the reaction pathways were calculated by finding the transition states connecting with the reactant and product complexes to better understand the photoredox reaction mechanism. In this Account, we summarize some of our time-resolved spectroscopic observations and characterization of water-assisted photoredox reactions of selected BPs and AQs. In the strong hydrogen-donor solvent isopropanol, the commonly studied photoreduction reaction for aromatic carbonyls via an intermolecular hydrogen atom tranfer process was observed for BPs and AQs. The photoredox reactions for the investigated BPs and AQs in aqueous environments occur on the triplet excited-state surface. Under moderately acidic aqueous conditions, the photoredox reactions for BPs and AQs are triggered by a proton transfer (PT) pathway. In neutral aqueous solutions, AQs may also undergo proton-coupled electron transfer (PCET) leading to the photoredox reaction, while BPs generate the ketyl radical species. Both BPs and AQs prefer the photohydration reaction in high-proton-concentration aqueous solutions (pH 0). The PT and PCET processes were found to offer more possibilities for the aromatic carbonyl compounds to lead to new photochemical reactions like the unusual photoredox reactions associated with BPs and AQs described here. Clear characterization of the photophysical pathways and the photochemical reactions of representative aromatic carbonyl compounds in aqueous environments not only provides fundamental information to better understand the photochemistry of carbonyl-containing compounds but also will facilitate the development of applications of these systems, like photochemical synthesis, drugs, and photolabile protecting groups. In addition, the importance of water molecules in the photochemical reactions of interest here may also lead to further understanding of how water influences the photochemistry of related carbonyl-containing compounds in aqueous environments.
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Affiliation(s)
- Jiani Ma
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi’an 710127, P. R. China
| | - Xiting Zhang
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
| | - David Lee Phillips
- Department of Chemistry, The University of Hong Kong, Pokfulam Road, Hong Kong, P. R. China
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19
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Cann JR, Cabanetos C, Welch GC. Synthesis of Molecular Dyads and Triads Based Upon N-Annulated Perylene Diimide Monomers and Dimers. European J Org Chem 2018. [DOI: 10.1002/ejoc.201801383] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Jonathan R. Cann
- Department of Chemistry; University of Calgary; 2500 University Drive N.W. T2N 1N4 Calgary Alberta Canada
| | - Clement Cabanetos
- CNRS UMR 6200, MOLTECH-Anjou; University of Angers; 2 Bd Lavoisier 49045 Angers France
| | - Gregory C. Welch
- Department of Chemistry; University of Calgary; 2500 University Drive N.W. T2N 1N4 Calgary Alberta Canada
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20
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Wu Y, Zhou J, Nelson JN, Young RM, Krzyaniak MD, Wasielewski MR. Covalent Radical Pairs as Spin Qubits: Influence of Rapid Electron Motion between Two Equivalent Sites on Spin Coherence. J Am Chem Soc 2018; 140:13011-13021. [DOI: 10.1021/jacs.8b08105] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Yilei Wu
- Department of Chemistry and Institute for Sustainability and Energy, Northwestern Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Jiawang Zhou
- Department of Chemistry and Institute for Sustainability and Energy, Northwestern Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Jordan N. Nelson
- Department of Chemistry and Institute for Sustainability and Energy, Northwestern Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Ryan M. Young
- Department of Chemistry and Institute for Sustainability and Energy, Northwestern Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Matthew D. Krzyaniak
- Department of Chemistry and Institute for Sustainability and Energy, Northwestern Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry and Institute for Sustainability and Energy, Northwestern Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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21
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Harvey SM, Phelan BT, Hannah DC, Brown KE, Young RM, Kirschner MS, Wasielewski MR, Schaller RD. Auger Heating and Thermal Dissipation in Zero-Dimensional CdSe Nanocrystals Examined Using Femtosecond Stimulated Raman Spectroscopy. J Phys Chem Lett 2018; 9:4481-4487. [PMID: 30011208 DOI: 10.1021/acs.jpclett.8b01504] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
We report femtosecond stimulated Raman spectroscopy (FSRS) measurements on dispersions of CdSe semiconductor nanocrystals (NCs) as a function of particle size and pump fluence. Upon photoexcitation, we observe depletion of stimulated Raman gain corresponding to generation of longitudinal optical (LO) phonons followed by recovery on picosecond timescales. At higher fluences, production of multiple excitons slows recovery of FSRS signals, which we attribute to sustained increases of LO phonon populations due to multiexcitonic Auger heating. Owing to the discretized electronic structure of these NCs, such heating cannot be readily monitored via electronic spectroscopic analysis of high-energy band tails as has been performed for higher-dimensional materials. Notably, recovery timescales exceed those of the biexcitonic Auger recombination process and as such reveal overall thermalization timescales likely owing to an acoustic phonon thermalization bottleneck that dictates the cooling timescale.
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Affiliation(s)
- Samantha M Harvey
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
- Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208 , United States
| | - Brian T Phelan
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
- Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208 , United States
| | - Daniel C Hannah
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
- Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208 , United States
| | - Kristen E Brown
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
- Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208 , United States
| | - Ryan M Young
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
- Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208 , United States
| | - Matthew S Kirschner
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
| | - Michael R Wasielewski
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
- Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208 , United States
| | - Richard D Schaller
- Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States
- Institute for Sustainability and Energy at Northwestern , Northwestern University , Evanston , Illinois 60208 , United States
- Center for Nanoscale Materials , Argonne National Laboratory , Argonne , Illinois 60439 , United States
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22
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Ashner MN, Tisdale WA. High repetition-rate femtosecond stimulated Raman spectroscopy with fast acquisition. OPTICS EXPRESS 2018; 26:18331-18340. [PMID: 30114014 DOI: 10.1364/oe.26.018331] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2018] [Accepted: 06/27/2018] [Indexed: 06/08/2023]
Abstract
Time-resolved femtosecond stimulated Raman spectroscopy (FSRS) is a powerful tool for investigating ultrafast structural and vibrational dynamics in light absorbing systems. However, the technique generally requires exposing a sample to high laser pulse fluences and long acquisition times to achieve adequate signal-to-noise ratios. Here, we describe a time-resolved FSRS instrument built around a Yb ultrafast amplifier operating at 200 kHz, and address some of the unique challenges that arise at high repetition-rates. The setup includes detection with a 9 kHz CMOS camera and an improved dual-chopping scheme to reject scattering artifacts that occur in the 3-pulse configuration. The instrument demonstrates good signal-to-noise performance while simultaneously achieving a 3-6 fold reduction in pulse energy and a 5-10 fold reduction in acquisition time relative to comparable 1 kHz instruments.
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23
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Lei YM, Xiao BQ, Liang WB, Chai YQ, Yuan R, Zhuo Y. A robust, magnetic, and self-accelerated electrochemiluminescent nanosensor for ultrasensitive detection of copper ion. Biosens Bioelectron 2018; 109:109-115. [DOI: 10.1016/j.bios.2018.03.013] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2017] [Revised: 03/05/2018] [Accepted: 03/06/2018] [Indexed: 12/19/2022]
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24
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Brown KE, Singh APN, Wu YL, Ma L, Mishra AK, Phelan BT, Young RM, Lewis FD, Wasielewski MR. Fluorescent excimers and exciplexes of the purine base derivative 8-phenylethynyl-guanine in DNA hairpins. Faraday Discuss 2018; 207:217-232. [PMID: 29362748 DOI: 10.1039/c7fd00186j] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The ground- and excited-state electronic interactions between the nucleobase analog 8-(4'-phenylethynyl)deoxyguanosine, EG, with natural nucleobases and 7-deazaguanine, as well as between adjacent EG base analogs, have been characterized using a combination of steady-state spectroscopy and time-resolved fluorescence, absorption, and stimulated Raman spectroscopies. The properties of the nucleoside EG-H2 are only weakly perturbed upon incorporation into synthetic DNA hairpins in which thymine, cytosine or adenine are the bases flanking EG. Incorporation of the nucleoside to be adjacent to guanine or deazaguanine results in the formation of short-lived (40-80 ps) exciplexes, the charge transfer character of which increases as the oxidation potential of the donor decreases. Hairpins possessing two or three adjacent EG base analogs display exciton-coupled circular dichroism in the ground state and form long-lived fluorescent excited states upon electronic excitation. Incorporation of EG into the helical scaffold of the DNA hairpins places it adjacent to its neighboring nucleobases or a second EG, thus providing the close proximity required for the formation of exciplex or excimer intermediates upon geometric relaxation of the short-lived EG excited state. The three time-resolved spectroscopic methods employed permit both the characterization of the several intermediates and the kinetics of their formation and decay.
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Affiliation(s)
- Kristen E Brown
- Department of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, USA.
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25
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Christensen JA, Phelan BT, Chaudhuri S, Acharya A, Batista VS, Wasielewski MR. Phenothiazine Radical Cation Excited States as Super-oxidants for Energy-Demanding Reactions. J Am Chem Soc 2018; 140:5290-5299. [DOI: 10.1021/jacs.8b01778] [Citation(s) in RCA: 64] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Joseph A. Christensen
- Department of Chemistry and Argonne−Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Brian T. Phelan
- Department of Chemistry and Argonne−Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Subhajyoti Chaudhuri
- Department of Chemistry and Argonne−Northwestern Solar Energy Research (ANSER) Center, Yale University, New Haven, Connecticut 06520, United States
| | - Atanu Acharya
- Department of Chemistry and Argonne−Northwestern Solar Energy Research (ANSER) Center, Yale University, New Haven, Connecticut 06520, United States
| | - Victor S. Batista
- Department of Chemistry and Argonne−Northwestern Solar Energy Research (ANSER) Center, Yale University, New Haven, Connecticut 06520, United States
| | - Michael R. Wasielewski
- Department of Chemistry and Argonne−Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
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26
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Wu Y, Zhou J, Phelan BT, Mauck CM, Stoddart JF, Young RM, Wasielewski MR. Probing Distance Dependent Charge-Transfer Character in Excimers of Extended Viologen Cyclophanes Using Femtosecond Vibrational Spectroscopy. J Am Chem Soc 2017; 139:14265-14276. [DOI: 10.1021/jacs.7b08275] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
- Yilei Wu
- Department of Chemistry,
Argonne-Northwestern Solar Energy Research Center, and Institute for
Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Jiawang Zhou
- Department of Chemistry,
Argonne-Northwestern Solar Energy Research Center, and Institute for
Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Brian T. Phelan
- Department of Chemistry,
Argonne-Northwestern Solar Energy Research Center, and Institute for
Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Catherine M. Mauck
- Department of Chemistry,
Argonne-Northwestern Solar Energy Research Center, and Institute for
Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - J. Fraser Stoddart
- Department of Chemistry,
Argonne-Northwestern Solar Energy Research Center, and Institute for
Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Ryan M. Young
- Department of Chemistry,
Argonne-Northwestern Solar Energy Research Center, and Institute for
Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry,
Argonne-Northwestern Solar Energy Research Center, and Institute for
Sustainability and Energy at Northwestern, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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27
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Powell DD, Wasielewski MR, Ratner MA. Redfield Treatment of Multipathway Electron Transfer in Artificial Photosynthetic Systems. J Phys Chem B 2017; 121:7190-7203. [PMID: 28661144 DOI: 10.1021/acs.jpcb.7b02748] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Coherence effects on electron transfer in a series of symmetric and asymmetric two-, three-, four-, and five-site molecular model systems for photosystem I in cyanobacteria and green plants were studied. The total site energies of the electronic Hamiltonian were calculated using the density functional theory (DFT) formalism and included the zero point vibrational energies of the electron donors and acceptors. Site energies and couplings were calculated using a polarizable continuum model to represent various solvent environments, and the site-to-site couplings were calculated using fragment charge difference methods at the DFT level of theory. The Redfield formalism was used to propagate the electron density from the donors to the acceptors, incorporating relaxation and dephasing effects to describe the electron transfer processes. Changing the relative energies of the donor, intermediate acceptor, and final acceptor molecules in these assemblies has profound effects on the electron transfer rates as well as on the amplitude of the quantum oscillations observed. Increasing the ratio of a particular energy gap to the electronic coupling for a given pair of states leads to weaker quantum oscillations between sites. Biasing the intermediate acceptor energies to slightly favor one pathway leads to a general decrease in electron transfer yield.
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Affiliation(s)
- Daniel D Powell
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Michael R Wasielewski
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center Northwestern University , Evanston, Illinois 60208-3113, United States
| | - Mark A Ratner
- Department of Chemistry and Argonne-Northwestern Solar Energy Research (ANSER) Center Northwestern University , Evanston, Illinois 60208-3113, United States
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28
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Mishra AK, Harris MA, Young RM, Wasielewski MR, Lewis FD. Dynamics of Charge Injection and Charge Recombination in DNA Mini-Hairpins. J Phys Chem B 2017. [DOI: 10.1021/acs.jpcb.7b03084] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Ashutosh Kumar Mishra
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research (ANSER) Center, and §Institute for
Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michelle A. Harris
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research (ANSER) Center, and §Institute for
Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M. Young
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research (ANSER) Center, and §Institute for
Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research (ANSER) Center, and §Institute for
Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Frederick D. Lewis
- Department
of Chemistry, ‡Argonne−Northwestern Solar Energy Research (ANSER) Center, and §Institute for
Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208-3113, United States
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29
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McAnally MO, Phelan BT, Young RM, Wasielewski MR, Schatz GC, Van Duyne RP. Quantitative Determination of the Differential Raman Scattering Cross Sections of Glucose by Femtosecond Stimulated Raman Scattering. Anal Chem 2017; 89:6931-6935. [DOI: 10.1021/acs.analchem.7b01335] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Affiliation(s)
- Michael O. McAnally
- Department
of Chemistry and ‡Argonne-Northwestern Solar Energy Research
Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Brian T. Phelan
- Department
of Chemistry and ‡Argonne-Northwestern Solar Energy Research
Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Ryan M. Young
- Department
of Chemistry and ‡Argonne-Northwestern Solar Energy Research
Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department
of Chemistry and ‡Argonne-Northwestern Solar Energy Research
Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - George C. Schatz
- Department
of Chemistry and ‡Argonne-Northwestern Solar Energy Research
Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Richard P. Van Duyne
- Department
of Chemistry and ‡Argonne-Northwestern Solar Energy Research
Center, Northwestern University, Evanston, Illinois 60208-3113, United States
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30
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Hall CR, Conyard J, Heisler IA, Jones G, Frost J, Browne WR, Feringa BL, Meech SR. Ultrafast Dynamics in Light-Driven Molecular Rotary Motors Probed by Femtosecond Stimulated Raman Spectroscopy. J Am Chem Soc 2017; 139:7408-7414. [PMID: 28486804 DOI: 10.1021/jacs.7b03599] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Photochemical isomerization in sterically crowded chiral alkenes is the driving force for molecular rotary motors in nanoscale machines. Here the excited-state dynamics and structural evolution of the prototypical light-driven rotary motor are followed on the ultrafast time scale by femtosecond stimulated Raman spectroscopy (FSRS) and transient absorption (TA). TA reveals a sub-100-fs blue shift and decay of the Franck-Condon bright state arising from relaxation along the reactive potential energy surface. The decay is accompanied by coherently excited vibrational dynamics which survive the excited-state structural evolution. The ultrafast Franck-Condon bright state relaxes to a dark excited state, which FSRS reveals to have a rich spectrum compared to the electronic ground state, with the most intense Raman-active modes shifted to significantly lower wavenumber. This is discussed in terms of a reduced bond order of the central bridging bond and overall weakening of bonds in the dark state, which is supported by electronic structure calculations. The observed evolution in the FSRS spectrum is assigned to vibrational cooling accompanied by partitioning of the dark state between the product isomer and the original ground state. Formation of the product isomer is observed in real time by FSRS. It is formed vibrationally hot and cools over several picoseconds, completing the characterization of the light-driven half of the photocycle.
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Affiliation(s)
- Christopher R Hall
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Jamie Conyard
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Ismael A Heisler
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Garth Jones
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - James Frost
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
| | - Wesley R Browne
- Molecular Inorganic Chemistry, Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747AG Groningen, The Netherlands
| | - Ben L Feringa
- Synthetic Organic Chemistry, Stratingh Institute for Chemistry, University of Groningen , Nijenborgh 4, 9747AG Groningen, The Netherlands
| | - Stephen R Meech
- School of Chemistry, University of East Anglia , Norwich Research Park, Norwich NR4 7TJ, U.K
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31
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Koch M, Myahkostupov M, Oblinsky DG, Wang S, Garakyaraghi S, Castellano FN, Scholes GD. Charge Localization after Ultrafast Photoexcitation of a Rigid Perylene Perylenediimide Dyad Visualized by Transient Stark Effect. J Am Chem Soc 2017; 139:5530-5537. [DOI: 10.1021/jacs.7b01630] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Marius Koch
- Department
of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08540, United States
| | - Mykhaylo Myahkostupov
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Daniel G. Oblinsky
- Department
of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08540, United States
| | - Siwei Wang
- Department
of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08540, United States
| | - Sofia Garakyaraghi
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Felix N. Castellano
- Department
of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Gregory D. Scholes
- Department
of Chemistry, Princeton University, Washington Road, Princeton, New Jersey 08540, United States
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32
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Spenst P, Young RM, Phelan BT, Keller M, Dostál J, Brixner T, Wasielewski MR, Würthner F. Solvent-Templated Folding of Perylene Bisimide Macrocycles into Coiled Double-String Ropes with Solvent-Sensitive Optical Signatures. J Am Chem Soc 2017; 139:2014-2021. [DOI: 10.1021/jacs.6b11973] [Citation(s) in RCA: 39] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
| | - Ryan M. Young
- Department
of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | - Brian T. Phelan
- Department
of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
| | | | | | | | - Michael R. Wasielewski
- Department
of Chemistry, Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208-3113, United States
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Abstract
Stimulated Raman scattering (SRS) describes a family of techniques first discovered and developed in the 1960s. Whereas the nascent history of the technique is parallel to that of laser light sources, recent advances have spurred a resurgence in its use and development that has spanned across scientific fields and spatial scales. SRS is a nonlinear technique that probes the same vibrational modes of molecules that are seen in spontaneous Raman scattering. While spontaneous Raman scattering is an incoherent technique, SRS is a coherent process, and this fact provides several advantages over conventional Raman techniques, among which are much stronger signals and the ability to time-resolve the vibrational motions. Technological improvements in pulse generation and detection strategies have allowed SRS to probe increasingly smaller volumes and shorter time scales. This has enabled SRS research to move from its original domain, of probing bulk media, to imaging biological tissues and single cells at the micro scale, and, ultimately, to characterizing samples with subdiffraction resolution at the nanoscale. In this Review, we give an overview of the history of the technique, outline its basic properties, and present historical and current uses at multiple length scales to underline the utility of SRS to the molecular sciences.
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Affiliation(s)
- Richard C Prince
- Department of Biomedical Engineering, University of California, Irvine , 1436 Natural Sciences II, Irvine, California 92697-2025, United States
| | - Renee R Frontiera
- Department of Chemistry, University of Minnesota, Minneapolis , B-18, 139 Smith Hall, 207 Pleasant Street SE, Minneapolis, Minnesota 55455-0431, United States
| | - Eric O Potma
- Department of Chemistry, University of California, Irvine , 1107 Natural Sciences II, Irvine, California 92697-2025, United States
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34
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Hole transport in DNA hairpins via base mismatches and strand crossings: Efficiency and dynamics. J Photochem Photobiol A Chem 2016. [DOI: 10.1016/j.jphotochem.2016.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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35
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Buchanan LE, Gruenke NL, McAnally MO, Negru B, Mayhew HE, Apkarian VA, Schatz GC, Van Duyne RP. Surface-Enhanced Femtosecond Stimulated Raman Spectroscopy at 1 MHz Repetition Rates. J Phys Chem Lett 2016; 7:4629-4634. [PMID: 27802054 DOI: 10.1021/acs.jpclett.6b02175] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Surface-enhanced femtosecond stimulated Raman spectroscopy (SE-FSRS) is an ultrafast Raman technique that combines the sensitivity of surface-enhanced Raman scattering with the temporal resolution of femtosecond stimulated Raman spectroscopy (FSRS). Here, we present the first successful implementation of SE-FSRS using a 1 MHz amplified femtosecond laser system. We compare SE-FSRS and FSRS spectra measured at 1 MHz and 100 kHz using both equal pump average powers and equal pump energies to demonstrate that higher repetition rates allow spectra with higher signal-to-noise ratios to be obtained at lower pulse energies, a significant advance in the implementation of SE-FSRS. The ability to use lower pulse energies significantly mitigates sample damage that results from plasmonic enhancement of high-energy ultrafast pulses. As a result of the improvements to SE-FSRS developed in this Letter, we believe that SE-FSRS is now poised to become a powerful tool for studying the dynamics of plasmonic materials and adsorbates thereon.
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Affiliation(s)
- Lauren E Buchanan
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Natalie L Gruenke
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Michael O McAnally
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Bogdan Negru
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Hannah E Mayhew
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Vartkess A Apkarian
- Department of Chemistry, University of California-Irvine , Irvine, California 92697, United States
| | - George C Schatz
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
| | - Richard P Van Duyne
- Department of Chemistry, Northwestern University , Evanston, Illinois 60208, United States
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36
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Renaud N, Harris MA, Singh APN, Berlin YA, Ratner MA, Wasielewski MR, Lewis FD, Grozema FC. Deep-hole transfer leads to ultrafast charge migration in DNA hairpins. Nat Chem 2016; 8:1015-1021. [DOI: 10.1038/nchem.2590] [Citation(s) in RCA: 52] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2015] [Accepted: 07/05/2016] [Indexed: 12/31/2022]
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37
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Pozzi EA, Gruenke NL, Chiang N, Zhdanov DV, Jiang N, Seideman T, Schatz GC, Hersam MC, Van Duyne RP. Operational Regimes in Picosecond and Femtosecond Pulse-Excited Ultrahigh Vacuum SERS. J Phys Chem Lett 2016; 7:2971-2976. [PMID: 27428724 DOI: 10.1021/acs.jpclett.6b01151] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
We report a systematic study performed in ultrahigh vacuum designed to identify the laser excitation regimes in which plasmonically enhanced ultrashort pulses may be used to nondestructively probe surface-bound molecules. A nondestructive, continuous-wave spectroscopic probe is used to monitor the effects of four different femtosecond- and picosecond-pulsed beams on the SER signals emanating from molecular analytes residing within plasmonically enhanced fields. We identify the roles of plasmonic amplification and alignment with a molecular electronic transition on the observed changes in the SER signals. Our results indicate that overlap of the laser wavelength with the plasmon resonance is the dominant contributor to signal degradation. In addition, signal loss for a given irradiation condition is observed only for molecules residing in hot spots above a threshold enhancement. Identification of suitable laser energy density ranges demonstrates the importance of considering these parameters when implementing SERS in the presence of pulsed irradiation.
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Affiliation(s)
- Eric A Pozzi
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
| | - Natalie L Gruenke
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
| | - Naihao Chiang
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
| | - Dmitry V Zhdanov
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
| | - Nan Jiang
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
| | - Tamar Seideman
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
| | - George C Schatz
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
| | - Mark C Hersam
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
| | - Richard P Van Duyne
- Department of Chemistry, ‡Department of Materials Science and Engineering, and §Applied Physics Program, Northwestern University , Evanston, Illinois 60208, United States
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38
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Batignani G, Pontecorvo E, Ferrante C, Aschi M, Elles CG, Scopigno T. Visualizing Excited-State Dynamics of a Diaryl Thiophene: Femtosecond Stimulated Raman Scattering as a Probe of Conjugated Molecules. J Phys Chem Lett 2016; 7:2981-8. [PMID: 27428853 DOI: 10.1021/acs.jpclett.6b01137] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Conjugated organic polymers based on substituted thiophene units are versatile building blocks of many photoactive materials, such as photochromic molecular switches or solar energy conversion devices. Unraveling the different processes underlying their photochemistry, such as the evolution on different electronic states and multidimensional structural relaxation, is a challenge critical to defining their function. Using femtosecond stimulated Raman scattering (FSRS) supported by quantum chemical calculations, we visualize the reaction pathway upon photoexcitation of the model compound 2-methyl-5-phenylthiophene. Specifically, we find that the initial wavepacket dynamics of the reaction coordinates occurs within the first ≈1.5 ps, followed by a ≈10 ps thermalization. Subsequent slow opening of the thiophene ring through a cleavage of the carbon-sulfur bond triggers an intersystem crossing to the triplet excited state. Our work demonstrates how a detailed mapping of the excited-state dynamics can be obtained, combining simultaneous structural sensitivity and ultrafast temporal resolution of FSRS with the chemical information provided by time-dependent density functional theory calculations.
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Affiliation(s)
- Giovanni Batignani
- Dipartimento di Fisica, Universitá di Roma "La Sapienza" , Roma I-00185, Italy
- Dipartimento di Scienze Fisiche e Chimiche, Universitá degli Studi dell'Aquila , L'Aquila I-67100, Italy
| | - Emanuele Pontecorvo
- 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
| | - Massimiliano Aschi
- Dipartimento di Scienze Fisiche e Chimiche, Universitá degli Studi dell'Aquila , L'Aquila I-67100, Italy
| | - Christopher G Elles
- Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States
| | - 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
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39
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Dietze DR, Mathies RA. Femtosecond Stimulated Raman Spectroscopy. Chemphyschem 2016; 17:1224-51. [DOI: 10.1002/cphc.201600104] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2016] [Indexed: 11/10/2022]
Affiliation(s)
- Daniel R. Dietze
- Department of Chemistry; University of California in Berkeley; CA Berkeley 94720 USA
| | - Richard A. Mathies
- Department of Chemistry; University of California in Berkeley; CA Berkeley 94720 USA
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40
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Dale EJ, Vermeulen NA, Juríček M, Barnes JC, Young RM, Wasielewski MR, Stoddart JF. Supramolecular Explorations: Exhibiting the Extent of Extended Cationic Cyclophanes. Acc Chem Res 2016; 49:262-73. [PMID: 26836816 DOI: 10.1021/acs.accounts.5b00495] [Citation(s) in RCA: 162] [Impact Index Per Article: 20.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Acting as hosts, cationic cyclophanes, consisting of π-electron-poor bipyridinium units, are capable of entering into strong donor-acceptor interactions to form host-guest complexes with various guests when the size and electronic constitution are appropriately matched. A synthetic protocol has been developed that utilizes catalytic quantities of tetrabutylammonium iodide to make a wide variety of cationic pyridinium-based cyclophanes in a quick and easy manner. Members of this class of cationic cyclophanes with boxlike geometries, dubbed Ex(n)Boxm(4+) for short, have been prepared by altering a number of variables: (i) n, the number of "horizontal" p-phenylene spacers between adjoining pyridinium units, to modulate the "length" of the cavity; (ii) m, the number of "vertical" p-phenylene spacers, to modulate the "width" of the cavity; and (iii) the aromatic linkers, namely, 1,4-di- and 1,3,5-trisubstituted units for the construction of macrocycles (ExBoxes) and macrobicycles (ExCages), respectively. This Account serves as an exploration of the properties that emerge from these structural modifications of the pyridinium-based hosts, coupled with a call for further investigation into the wealth of properties inherent in this class of compounds. By variation of only the aforementioned components, the role of these cationic receptors covers ground that spans (i) synthetic methodology, (ii) extraction and sequestration, (iii) catalysis, (iv) molecular electronics, (v) physical organic chemistry, and (vi) supramolecular chemistry. Ex(1)Box(4+) (or simply ExBox(4+)) has been shown to be a multipurpose receptor capable of binding a wide range of polycyclic aromatic hydrocarbons (PAHs), while also being a suitable component in switchable mechanically interlocked molecules. Additionally, the electronic properties of some host-guest complexes allow the development of artificial photosystems. Ex(2)Box(4+) boasts the ability to bind both π-electron-rich and -poor aromatic guests in different binding sites located within the same cavity. ExBox2(4+) forms complexes with C60 in which discrete arrays of aligned fullerenes result in single cocrystals, leading to improved material conductivities. When the substitution pattern of the Ex(n)Box(4+) series is changed to 1,3,5-trisubstituted benzenoid cores, the hexacationic cagelike compound, termed ExCage(6+), exhibits different kinetics of complexation with guests of varying sizes-a veritable playground for physical organic chemists. The organization of functionality with respect to structure becomes valuable as the number of analogues continues to grow. With each of these minor structural modifications, a wealth of properties emerge, begging the question as to what discoveries await and what properties will be realized with the continued exploration of this area of supramolecular chemistry based on a unique class of receptor molecules.
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Affiliation(s)
- Edward J. Dale
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Nicolaas A. Vermeulen
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Michal Juríček
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Jonathan C. Barnes
- Department of Chemistry, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, Massachusetts 02139, United States
| | - Ryan M. Young
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
- Argonne−Northwestern Solar Energy Research (ANSER) Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - Michael R. Wasielewski
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
- Argonne−Northwestern Solar Energy Research (ANSER) Center, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
| | - J. Fraser Stoddart
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, United States
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41
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Wu YC, Zhao B, Lee SY. Time-dependent wave packet averaged vibrational frequencies from femtosecond stimulated Raman spectra. J Chem Phys 2016; 144:054104. [DOI: 10.1063/1.4941057] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022] Open
Affiliation(s)
- Yue-Chao Wu
- Division of Physics & Applied Physics, and Division of Chemistry & Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Bin Zhao
- Division of Physics & Applied Physics, and Division of Chemistry & Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
| | - Soo-Y. Lee
- Division of Physics & Applied Physics, and Division of Chemistry & Biological Chemistry, School of Physical & Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore
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42
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Gruenke NL, Cardinal MF, McAnally MO, Frontiera RR, Schatz GC, Van Duyne RP. Ultrafast and nonlinear surface-enhanced Raman spectroscopy. Chem Soc Rev 2016; 45:2263-90. [PMID: 26848784 DOI: 10.1039/c5cs00763a] [Citation(s) in RCA: 120] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Ultrafast surface-enhanced Raman spectroscopy (SERS) has the potential to study molecular dynamics near plasmonic surfaces to better understand plasmon-mediated chemical reactions such as plasmonically-enhanced photocatalytic or photovoltaic processes. This review discusses the combination of ultrafast Raman spectroscopic techniques with plasmonic substrates for high temporal resolution, high sensitivity, and high spatial resolution vibrational spectroscopy. First, we introduce background information relevant to ultrafast SERS: the mechanisms of surface enhancement in Raman scattering, the characterization of plasmonic materials with ultrafast techniques, and early complementary techniques to study molecule-plasmon interactions. We then discuss recent advances in surface-enhanced Raman spectroscopies with ultrafast pulses with a focus on the study of molecule-plasmon coupling and molecular dynamics with high sensitivity. We also highlight the challenges faced by this field by the potential damage caused by concentrated, highly energetic pulsed fields in plasmonic hotspots, and finally the potential for future ultrafast SERS studies.
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Affiliation(s)
- Natalie L Gruenke
- Department of Chemistry, Northwestern University, 2145 Sheridan Road, Evanston, Illinois 60208, USA.
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43
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Myahkostupov M, Castellano FN. Tetrahedral rigid core antenna chromophores bearing bay-substituted perylenediimides. Tetrahedron 2015. [DOI: 10.1016/j.tet.2015.10.083] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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44
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Hoffman DP, Leblebici SY, Schwartzberg AM, Mathies RA. Exciton Mobility in Organic Photovoltaic Heterojunctions from Femtosecond Stimulated Raman. J Phys Chem Lett 2015; 6:2919-2923. [PMID: 26267181 DOI: 10.1021/acs.jpclett.5b01436] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Exciton mobility is crucial to organic photovoltaic (OPV) efficiency, but accurate, quantitative measures and therefore precise understanding of this process are currently lacking. Here, we exploit the unique capabilities of femtosecond stimulated Raman spectroscopy (FSRS) to disentangle the signatures of the bulk and interfacial donor response in a bulk heterojunction composed of poly[2-methoxy-5-(3',7'-dimethyloctyloxy)-1,4-phenylenevinylene] (MDMO-PPV) and phenyl-C61-butyric acid methyl ester (PCBM). Surprisingly, we find that donor excitons are very mobile for the first ∼300 fs following excitation (before thermalization) even though their overall lifetime is significantly longer (170 ps). A sharp decrease in mobility occurs after the system relaxes out of the Franck-Condon (FC) region. From this observation we predict that any polymer lacking a significant resonance Raman effect and fluorescence Stokes shift, indicating slow FC relaxation and small reorganization energy, will make an efficient OPV material.
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Affiliation(s)
| | - Sibel Y Leblebici
- §Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
| | - Adam M Schwartzberg
- §Molecular Foundry, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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45
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Gardner DM, Chen HF, Krzyaniak MD, Ratner MA, Wasielewski MR. Large Dipolar Spin–Spin Interaction in a Photogenerated U-Shaped Triradical. J Phys Chem A 2015; 119:8040-8. [DOI: 10.1021/acs.jpca.5b03048] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Daniel M. Gardner
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Hsiao-Fan Chen
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Matthew D. Krzyaniak
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Mark A. Ratner
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
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46
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Dyar SM, Margulies EA, Horwitz NE, Brown KE, Krzyaniak MD, Wasielewski MR. Photogenerated Quartet State Formation in a Compact Ring-Fused Perylene-Nitroxide. J Phys Chem B 2015; 119:13560-9. [DOI: 10.1021/acs.jpcb.5b02378] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Scott M. Dyar
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Eric A. Margulies
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Noah E. Horwitz
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Kristen E. Brown
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Matthew D. Krzyaniak
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
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47
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Son M, Park KH, Yoon MC, Kim P, Kim D. Excited-State Vibrational Coherence in Perylene Bisimide Probed by Femtosecond Broadband Pump-Probe Spectroscopy. J Phys Chem A 2015; 119:6275-82. [PMID: 25992707 DOI: 10.1021/acs.jpca.5b03571] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Broadband laser pulses with ultrashort duration are capable of triggering impulsive excitation of the superposition of vibrational eigenstates, giving rise to quantum beating signals originating from coherent wave packet motions along the potential energy surface. In this work, coherent vibrational wave packet dynamics of an N,N'-bis(2,6-dimethylphenyl)perylene bisimide (DMP-PBI) were investigated by femtosecond broadband pump-probe spectroscopy which features fast and balanced data acquisition with a wide spectral coverage of >200 nm. Clear modulations were observed in the envelope of the stimulated emission decay profiles of DMP-PBI with the oscillation frequencies of 140 and 275 cm(-1). Fast Fourier transform analysis of each oscillatory mode revealed characteristic phase jumps near the maxima of the steady-state fluorescence, indicating that the observed vibrational coherence originates from an excited-state wave packet motion. Quantum calculations of the normal modes at the low-frequency region suggest that low-frequency C-C (C═C) stretching motions accompanied by deformation of the dimethylphenyl substituents are responsible for the manifestation of such coherent wave packet dynamics.
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Affiliation(s)
- Minjung Son
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 120-749, Korea
| | - Kyu Hyung Park
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 120-749, Korea
| | - Min-Chul Yoon
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 120-749, Korea
| | - Pyosang Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 120-749, Korea
| | - Dongho Kim
- Spectroscopy Laboratory for Functional π-Electronic Systems and Department of Chemistry, Yonsei University, Seoul 120-749, Korea
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48
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Dyar SM, Smeigh AL, Karlen SD, Young RM, Wasielewski MR. Photo-initiated multi-step electron transfer in donor–acceptor systems using a novel bi-functionalized perylene chromophore. Chem Phys Lett 2015. [DOI: 10.1016/j.cplett.2015.04.020] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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49
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Young RM, Singh APN, Thazhathveetil AK, Cho VY, Zhang Y, Renaud N, Grozema FC, Beratan DN, Ratner MA, Schatz GC, Berlin YA, Lewis FD, Wasielewski MR. Charge Transport across DNA-Based Three-Way Junctions. J Am Chem Soc 2015; 137:5113-22. [DOI: 10.1021/jacs.5b00931] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- Ryan M. Young
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
- Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Arunoday P. N. Singh
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Arun K. Thazhathveetil
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Vincent Y. Cho
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Yuqi Zhang
- Departments
of Chemistry, Biochemistry, and Physics, Duke University
, Durham, North Carolina
27708, United States
| | - Nicolas Renaud
- DelftChemTech, Delft University of Technology
, Julianalaan 136, 2628 BL
Delft, The Netherlands
| | - Ferdinand C. Grozema
- DelftChemTech, Delft University of Technology
, Julianalaan 136, 2628 BL
Delft, The Netherlands
| | - David N. Beratan
- Departments
of Chemistry, Biochemistry, and Physics, Duke University
, Durham, North Carolina
27708, United States
| | - Mark A. Ratner
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - George C. Schatz
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Yuri A. Berlin
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Frederick D. Lewis
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
| | - Michael R. Wasielewski
- Department
of Chemistry, Northwestern University
, Evanston, Illinois
60208-3113, United States
- Argonne-Northwestern
Solar Energy Research (ANSER) Center, Northwestern University
, Evanston, Illinois
60208-3113, United States
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50
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Wu YL, Brown KE, Gardner DM, Dyar SM, Wasielewski MR. Photoinduced Hole Injection into a Self-Assembled π-Extended G-Quadruplex. J Am Chem Soc 2015; 137:3981-90. [DOI: 10.1021/jacs.5b00977] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Affiliation(s)
- Yi-Lin Wu
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Kristen E. Brown
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Daniel M. Gardner
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Scott M. Dyar
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
| | - Michael R. Wasielewski
- Department of Chemistry and
Argonne-Northwestern Solar Energy Research (ANSER) Center, Northwestern University, Evanston, Illinois 60208-3113, United States
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