1
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Mendis KC, Li X, Valdiviezo J, Banziger SD, Zhang P, Ren T, Beratan DN, Rubtsov IV. Electron transfer rate modulation with mid-IR in butadiyne-bridged donor-bridge-acceptor compounds. Phys Chem Chem Phys 2024; 26:1819-1828. [PMID: 38168814 DOI: 10.1039/d3cp03175f] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2024]
Abstract
Controlling electron transfer (ET) processes in donor-bridge-acceptor (DBA) compounds by mid-IR excitation can enhance our understanding of the ET dynamics and may find practical applications in molecular sensing and molecular-scale electronics. Alkyne moieties are attractive to serve as ET bridges, as they offer the possibility of fast ET and present convenient vibrational modes to perturb the ET dynamics. Yet, these bridges introduce complexity because of the strong torsion angle dependence of the ET rates and transition dipoles among electronic states and a shallow torsion barrier. In this study, we implemented ultrafast 3-pulse laser spectroscopy to investigate how the ET from the dimethyl aniline (D) electron donor to the N-isopropyl-1,8-napthalimide (NAP) electron acceptor can be altered by exciting the CC stretching mode (νCC) of the butadiyne bridge linking the donor and acceptor. The electron transfer was initiated by electronically exciting the acceptor moiety at 400 nm, followed by vibrational excitation of the alkyne, νCC, and detecting the changes in the absorption spectrum in the visible spectral region. The experiments were performed at different delay times t1 and t2, which are the delays between UV-mid-IR and mid-IR-Vis pulses, respectively. Two sets of torsion-angle conformers were identified, one featuring a very fast mean ET time of 0.63 ps (group A) and another featuring a slower mean ET time of 4.3 ps (group B), in the absence of the mid-IR excitation. TD-DFT calculations were performed to determine key torsion angle dependent molecular parameters, including the electronic and vibrational transition dipoles, transition frequencies, and electronic couplings. To describe the 3-pulse data, we developed a kinetic model that includes a locally excited, acceptor-based S2 state, a charge separated S1 state, and their vibrationally excited counterparts, with either excited νCC (denoted as S1Atr, S1Btr, S2Atr, and S2Btr, where tr stands for the excited triplet bond, νCC) or excited daughter modes of the νCC relaxation (S1Ah, S1Bh, S2Ah, and S2Bh, where h stands for vibrationally hot species). The kinetic model was solved analytically, and the species-associated spectra (SAS) were determined numerically using a matrix approach, treating first the experiments with longer t1 delays and then using the already determined SAS for modeling the experiments with shorter t1 delays. Strong vibronic coupling of νCC and of vibrationally hot states makes the analysis complicated. Nevertheless, the SAS were identified and the ET rates of the vibrationally excited species, S2Atr, S2Btr and S2Bh, were determined. The results show that the ET rate for the S2A species is ca. 1.2-fold slower when the νCC mode is excited. The ET rate for species S2B is slower by ca. 1.3-fold if the compound is vibrationally hot and is essentially unchanged when the νCC mode is excited. The SAS determined for the tr and h species resemble the SAS for their respective precursor species in the 2-pulse transient absorption experiments, which validates the procedure used and the results.
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Affiliation(s)
- Kasun C Mendis
- Department of Chemistry, Tulane University, New Orleans, LA 70118, USA.
| | - Xiao Li
- Department of Chemistry, Tulane University, New Orleans, LA 70118, USA.
| | - Jesús Valdiviezo
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Susannah D Banziger
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
| | - Peng Zhang
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
| | - Tong Ren
- Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, USA
| | - David N Beratan
- Department of Chemistry, Duke University, Durham, North Carolina 27708, USA
- Department of Physics, Duke University, Durham, North Carolina 27708, USA
- Department of Biochemistry, Duke University, Durham, North Carolina 27710, USA
| | - Igor V Rubtsov
- Department of Chemistry, Tulane University, New Orleans, LA 70118, USA.
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2
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Ye Q, Cairnie DR, Troya D, Kumar N, Yang X, Morris AJ. Photoinduced Dynamic Ligation in Metal-Organic Frameworks. J Am Chem Soc 2024; 146:101-105. [PMID: 38150536 PMCID: PMC10785796 DOI: 10.1021/jacs.3c12217] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2023] [Revised: 12/12/2023] [Accepted: 12/13/2023] [Indexed: 12/29/2023]
Abstract
Metal organic frameworks (MOFs), a class of porous crystalline materials consisting of metal-based nodes and organic linkers, have emerged as a promising platform for photocatalysis due to their ultrahigh functional surface area, customizable topologies, and tunable energetics. While interesting photochemistry has been reported, the related photoinduced structural dynamics of MOFs remains unclear. The consensus is that the coordination bonds between MOF nodes and linkers are considered static during photoexcitation, while the open-metal sites on the nodes are taken as the key active sites for catalysis. In this work, through a complementary time-resolved visible and infrared (IR) spectroscopic investigation, along with computational studies, we report for the first time light-induced structural bond dissociation (COO-M) and reformation in an iron-oxo framework, MIL-101(Fe). The probed excited state displayed ligand-to-metal charge transfer (LMCT) characteristics and exhibited a ca. 30 μs lifetime. The incredibly long excited-state lifetime led us to probe potential structural rearrangements that facilitated charge separation in MIL-101(Fe). By probing the vibrational fingerprints of the carboxylate linker upon LMCT photoexcitation, we observed the reversible transition of the carboxylate-Fe bond from a bidentate bridging mode to a monodentate mode, indicating the partial dissociation of the carboxylate ligand. Importantly, the bidentate configuration is recovered on the same time scale of the excited state lifetimes as probed via visible transient absorption spectroscopy. The elucidated photoinduced configurational dynamics provides a foundation for an in-depth understanding of MOF-based photocatalytic mechanisms.
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Affiliation(s)
- Qingyu Ye
- Department
of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Daniel R. Cairnie
- Department
of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Diego Troya
- Department
of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Naveen Kumar
- Department
of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Xiaozhou Yang
- Department
of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
| | - Amanda J. Morris
- Department
of Chemistry, Virginia Tech, Blacksburg, Virginia 24060, United States
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3
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Phelps R, Etcheverry-Berrios A, Brechin EK, Johansson JO. Equatorial restriction of the photoinduced Jahn-Teller switch in Mn(iii)-cyclam complexes. Chem Sci 2023; 14:6621-6630. [PMID: 37350826 PMCID: PMC10284123 DOI: 10.1039/d3sc01506h] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Accepted: 05/25/2023] [Indexed: 06/24/2023] Open
Abstract
Ultrafast transient absorption spectra were recorded for solutions of [MnIII(cyclam)(H2O)(OTf)][OTf]2 (cyclam = 1,4,8,11-tetraazacyclotetradecane and OTf = trifluoromethanesulfonate) in water to explore the possibility to restrict the equatorial expansion following photoexcitation of the dxy ← dz2 electronic transition, often resulting in a switch from axial to equatorial Jahn-Teller distortion in MnIII complexes. Strong oscillations were observed in the excited state absorption signal and were attributed to an excited state wavepacket. The structural rigidity of the cyclam ligand causes a complex reaction coordinate with frequencies of 333, 368, 454 and 517 cm-1, and a significantly shorter compressed-state lifetime compared to other MnIII complexes with less restricted equatorial ligands. Complementary density functional theory quantum chemistry calculations indicate a switch from an axially elongated to a compressed structure in the first excited quintet state Q1, which is accompanied by a modulation of the axial tilt angle. Computed harmonic frequencies for the axial stretching mode (∼379 cm-1) and the equatorial expansions (∼410 and 503 cm-1) of the Q1 state agree well with the observed coherences and indicate that the axial bond length contraction is significantly larger than the equatorial expansion, which implies a successful restriction of the wavepacket motion. The weak oscillation observed around 517 cm-1 is assigned to a see-saw motion of the axial tilt (predicted ∼610 cm-1). The results provide insights into the structural perturbations to the molecular evolution along excited state potential energy surfaces of MnIII octahedral complexes and can be used to guide the synthesis of optically controlled MnIII-based single-molecule magnets.
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Affiliation(s)
- Ryan Phelps
- EaStCHEM School of Chemistry, University of Edinburgh David Brewster Road EH9 3FJ Edinburgh UK
| | | | - Euan K Brechin
- EaStCHEM School of Chemistry, University of Edinburgh David Brewster Road EH9 3FJ Edinburgh UK
| | - J Olof Johansson
- EaStCHEM School of Chemistry, University of Edinburgh David Brewster Road EH9 3FJ Edinburgh UK
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4
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Jones RW, Auty AJ, Wu G, Persson P, Appleby MV, Chekulaev D, Rice CR, Weinstein JA, Elliott PIP, Scattergood PA. Direct Determination of the Rate of Intersystem Crossing in a Near-IR Luminescent Cr(III) Triazolyl Complex. J Am Chem Soc 2023. [PMID: 37224437 DOI: 10.1021/jacs.3c01543] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
A detailed understanding of the dynamics of photoinduced processes occurring in the electronic excited state is essential in informing the rational design of photoactive transition-metal complexes. Here, the rate of intersystem crossing in a Cr(III)-centered spin-flip emitter is directly determined through the use of ultrafast broadband fluorescence upconversion spectroscopy (FLUPS). In this contribution, we combine 1,2,3-triazole-based ligands with a Cr(III) center and report the solution-stable complex [Cr(btmp)2]3+ (btmp = 2,6-bis(4-phenyl-1,2,3-triazol-1-yl-methyl)pyridine) (13+), which displays near-infrared (NIR) luminescence at 760 nm (τ = 13.7 μs, ϕ = 0.1%) in fluid solution. The excited-state properties of 13+ are probed in detail through a combination of ultrafast transient absorption (TA) and femtosecond-to-picosecond FLUPS. Although TA spectroscopy allows us to observe the evolution of phosphorescent excited states within the doublet manifold, more significantly and for the first time for a complex of Cr(III), we utilize FLUPS to capture the short-lived fluorescence from initially populated quartet excited states immediately prior to the intersystem crossing process. The decay of fluorescence from the low-lying 4MC state therefore allows us to assign a value of (823 fs)-1 to the rate of intersystem crossing. Importantly, the sensitivity of FLUPS to only luminescent states allows us to disentangle the rate of intersystem crossing from other closely associated excited-state events, something which has not been possible in the spectroscopic studies previously reported for luminescent Cr(III) systems.
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Affiliation(s)
- Robert W Jones
- Department of Chemistry, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, U.K
| | - Alexander J Auty
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, U.K
| | - Guanzhi Wu
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, U.K
| | - Petter Persson
- Division of Theoretical Chemistry, Department of Chemistry, Lund University, Box 124, SE-22100 Lund, Sweden
| | - Martin V Appleby
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, U.K
| | - Dimitri Chekulaev
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, U.K
| | - Craig R Rice
- Department of Chemistry, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, U.K
| | - Julia A Weinstein
- Department of Chemistry, University of Sheffield, Brook Hill, Sheffield S3 7HF, U.K
| | - Paul I P Elliott
- Department of Chemistry, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, U.K
| | - Paul A Scattergood
- Department of Chemistry, University of Huddersfield, Queensgate, Huddersfield HD1 3DH, U.K
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5
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Sinha N, Wenger OS. Photoactive Metal-to-Ligand Charge Transfer Excited States in 3d 6 Complexes with Cr 0, Mn I, Fe II, and Co III. J Am Chem Soc 2023; 145:4903-4920. [PMID: 36808978 PMCID: PMC9999427 DOI: 10.1021/jacs.2c13432] [Citation(s) in RCA: 39] [Impact Index Per Article: 39.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023]
Abstract
Many coordination complexes and organometallic compounds with the 4d6 and 5d6 valence electron configurations have outstanding photophysical and photochemical properties, which stem from metal-to-ligand charge transfer (MLCT) excited states. This substance class makes extensive use of the most precious and least abundant metal elements, and consequently there has been a long-standing interest in first-row transition metal compounds with photoactive MLCT states. Semiprecious copper(I) with its completely filled 3d subshell is a relatively straightforward and well explored case, but in 3d6 complexes the partially filled d-orbitals lead to energetically low-lying metal-centered (MC) states that can cause undesirably fast MLCT excited state deactivation. Herein, we discuss recent advances made with isoelectronic Cr0, MnI, FeII, and CoIII compounds, for which long-lived MLCT states have become accessible over the past five years. Furthermore, we discuss possible future developments in the search for new first-row transition metal complexes with partially filled 3d subshells and photoactive MLCT states for next-generation applications in photophysics and photochemistry.
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Affiliation(s)
- Narayan Sinha
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
| | - Oliver S Wenger
- Department of Chemistry, University of Basel, St. Johanns-Ring 19, 4056 Basel, Switzerland
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6
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Boeije Y, Olivucci M. From a one-mode to a multi-mode understanding of conical intersection mediated ultrafast organic photochemical reactions. Chem Soc Rev 2023; 52:2643-2687. [PMID: 36970950 DOI: 10.1039/d2cs00719c] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/29/2023]
Abstract
This review discusses how ultrafast organic photochemical reactions are controlled by conical intersections, highlighting that decay to the ground-state at multiple points of the intersection space results in their multi-mode character.
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Affiliation(s)
- Yorrick Boeije
- Van 't Hoff Institute for Molecular Sciences (HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands
| | - Massimo Olivucci
- Chemistry Department, University of Siena, Via Aldo Moro n. 2, 53100 Siena, Italy
- Chemistry Department, Bowling Green State University, Overman Hall, Bowling Green, Ohio 43403, USA
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7
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Semiclassical Theory of Multistage Nonequilibrium Electron Transfer in Macromolecular Compounds in Polar Media with Several Relaxation Timescales. Int J Mol Sci 2022; 23:ijms232415793. [PMID: 36555434 PMCID: PMC9779366 DOI: 10.3390/ijms232415793] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 12/07/2022] [Accepted: 12/09/2022] [Indexed: 12/14/2022] Open
Abstract
Many specific features of ultrafast electron transfer (ET) reactions in macromolecular compounds can be attributed to nonequilibrium configurations of intramolecular vibrational degrees of freedom and the environment. In photoinduced ET, nonequilibrium nuclear configurations are often produced at the stage of optical excitation, but they can also be the result of electron tunneling itself, i.e., fast redistribution of charges within the macromolecule. A consistent theoretical description of ultrafast ET requires an explicit consideration of the nuclear subsystem, including its evolution between electron jumps. In this paper, the effect of the multi-timescale nuclear reorganization on ET transitions in macromolecular compounds is studied, and a general theory of ultrafast ET in non-Debye polar environments with a multi-component relaxation function is developed. Particular attention is paid to designing the multidimensional space of nonequilibrium nuclear configurations, as well as constructing the diabatic free energy surfaces for the ET states. The reorganization energies of individual ET transitions, the equilibrium energies of ET states, and the relaxation properties of the environment are used as input data for the theory. The effect of the system-environment interaction on the ET kinetics is discussed, and mechanisms for enhancing the efficiency of charge separation in macromolecular compounds are analyzed.
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8
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Paulus BC, McCusker JK. On the use of vibronic coherence to identify reaction coordinates for ultrafast excited-state dynamics of transition metal-based chromophores. Faraday Discuss 2022; 237:274-299. [PMID: 35661840 DOI: 10.1039/d2fd00106c] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
The question of whether one can use information from quantum coherence as a means of identifying vibrational degrees of freedom that are active along an excited-state reaction coordinate is discussed. Specifically, we are exploring the notion of whether quantum oscillations observed in single-wavelength kinetics data exhibiting coherence dephasing times that are intermediate between that expected for either pure electronic or pure vibrational dephasing are vibronic in nature and therefore may be coupled to electronic state-to-state evolution. In the case of a previously published Fe(II) polypyridyl complex, coherences observed subsequent to 1A1 → 1MLCT excitation were linked to large-amplitude motion of a portion of the ligand framework; dephasing times on the order of 200-300 fs suggested that these degrees of freedom could be associated with ultrafast (∼100 fs) conversion from the initially formed MLCT excited state to lower-energy, metal-centered ligand-field excited state(s) of the compound. Incorporation of an electronically benign but sterically restrictive Cu(I) ion into the superstructure designed to interfere with this motion yielded a compound exhibiting a ∼25-fold increase in the compound's MLCT lifetime, a result that was interpreted as confirmation of the initial hypothesis. However, new data acquired on a different chemical system - Cr(acac')3 (where acac' represents various derivatives of acetylacetonate) - yielded results that call into question this same hypothesis. Coherences observed subsequent to 4A2 → 4T2 ligand-field excitation on a series of molecules implicated similar vibrational degrees of freedom across the series, but exhibited dephasing times ranging from 340 fs to 2.5 ps without any clear correlation to the dynamics of excited-state evolution in the system. Taken together, the results obtained on both of these chemical platforms suggest that while identification of coherences can indeed point to degrees of freedom that should be considered as candidate modes for defining reaction trajectories, our understanding of the factors that determine the interplay across coherences, dephasing times, and electronic and geometric structure is insufficient at the present time to view this parameter as a robust metric for differentiating active versus spectator modes for ultrafast dynamics.
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Affiliation(s)
- Bryan C Paulus
- Department of Chemistry, Michigan State University, 578 South Shaw Lane, East Lansing, MI 48824, USA.
| | - James K McCusker
- Department of Chemistry, Michigan State University, 578 South Shaw Lane, East Lansing, MI 48824, USA.
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9
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Barlow K, Eng J, Ivalo I, Coletta M, Brechin EK, Penfold TJ, Johansson JO. Photoinduced Jahn-Teller switch in Mn(III) terpyridine complexes. Dalton Trans 2022; 51:10751-10757. [PMID: 35583816 DOI: 10.1039/d2dt00889k] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultrafast transient absorption spectra were recorded for [Mn(terpy)X3], where X = Cl, F, and N3, to explore photoinduced switching from axial to equatorial Jahn-Teller (JT) distortion. Strong oscillations were observed in the transients, corresponding to a wavepacket on the excited-state potential energy surface with oscillation frequency around 115 cm-1 for all three complexes. Multireference quantum chemistry calculations indicate that the reaction coordinate is a pincer-like motion of the terpyridine ligand arising from bond length changes in the excited state due to the JT switch. We observed long dephasing times of the wavepacket, with times of 620 fs for [Mn(terpy)Cl3], 450 fs for [Mn(terpy)F3], and 370 fs for [Mn(terpy)(N3)3]. The dephasing time of these coherences decreases with an increasing number of vibrational modes at lower energy than the mode dominating the reaction coordinate, suggesting they act as an effective bath to dissipate the excess energy obtained from photoexcitation.
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Affiliation(s)
- Kyle Barlow
- EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, EH9 3FJ, Edinburgh, UK.
| | - Julien Eng
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - Iona Ivalo
- EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, EH9 3FJ, Edinburgh, UK.
| | - Marco Coletta
- EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, EH9 3FJ, Edinburgh, UK.
| | - Euan K Brechin
- EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, EH9 3FJ, Edinburgh, UK.
| | - Thomas J Penfold
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle Upon Tyne, UK
| | - J Olof Johansson
- EaStCHEM School of Chemistry, University of Edinburgh, David Brewster Road, EH9 3FJ, Edinburgh, UK.
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10
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Farrow GA, Quick M, Kovalenko SA, Wu G, Sadler A, Chekulaev D, Chauvet AAP, Weinstein JA, Ernsting NP. On the intersystem crossing rate in a Platinum(II) donor-bridge-acceptor triad. Phys Chem Chem Phys 2021; 23:21652-21663. [PMID: 34580688 DOI: 10.1039/d1cp03471e] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
The rates of ultrafast intersystem crossing in acceptor-bridge-donor molecules centered on Pt(II) acetylides are investigated. Specifically, a Pt(II) trans-acetylide triad NAP--Pt--Ph-CH2-PTZ [1], with acceptor 4-ethynyl-N-octyl-1,8-naphthalimide (NAP) and donor phenothiazine (PTZ), is examined in detail. We have previously shown that optical excitation in [1] leads to a manifold of singlet charge-transfer states, S*, which evolve via a triplet charge-transfer manifold into a triplet state 3NAP centered on the acceptor ligand and partly to a charge-separated state 3CSS (NAP--Pt-PTZ+). A complex cascade of electron transfer processes was observed, but intersystem crossing (ISC) rates were not explicitly resolved due to lack of spin selectivity of most ultrafast spectroscopies. Here we revisit the question of ISC with a combination and complementary analysis of (i) transient absorption, (ii) ultrafast broadband fluorescence upconversion, FLUP, which is only sensitive to emissive states, and (iii) femtosecond stimulated Raman spectroscopy, FSR. Raman resonance conditions allow us to observe S* and 3NAP exclusively by FSR, through vibrations which are pertinent only to these two states. This combination of methods enabled us to extract the intersystem crossing rates that were not previously accessible. Multiple timescales (1.6 ps to ∼20 ps) are associated with the rise of triplet species, which can now be assigned conclusively to multiple ISC pathways from a manifold of hot charge-transfer singlet states. The analysis is consistent with previous transient infrared spectroscopy data. A similar rate of ISC, up to 20 ps, is observed in the trans-acetylide NAP--Pt--Ph [2] which maintains two acetylide groups across the platinum center but lacks a donor unit, whilst removal of one acetylide group in mono-acetylide NAP--Pt-Cl [3] leads to >10-fold deceleration of the intersystem crossing process. Our work provides insight on the intersystem crossing dynamics of the organo-metallic complexes, and identifies a general method based on complementary ultrafast spectroscopies to disentangle complex spin, electronic and vibrational processes following photoexcitation.
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Affiliation(s)
- G A Farrow
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.
| | - M Quick
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
| | - S A Kovalenko
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
| | - G Wu
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.
| | - A Sadler
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.
| | - D Chekulaev
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.
| | - A A P Chauvet
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.
| | - J A Weinstein
- Department of Chemistry, University of Sheffield, Sheffield, S3 7HF, UK.
| | - N P Ernsting
- Department of Chemistry, Humboldt-Universität zu Berlin, Brook-Taylor-Str. 2, 12489 Berlin, Germany.
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11
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Kim P, Valentine AJS, Roy S, Mills AW, Chakraborty A, Castellano FN, Li X, Chen LX. Ultrafast Excited-State Dynamics of Photoluminescent Pt(II) Dimers Probed by a Coherent Vibrational Wavepacket. J Phys Chem Lett 2021; 12:6794-6803. [PMID: 34270259 DOI: 10.1021/acs.jpclett.1c01289] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Intricate potential energy surfaces (PESs) of some transition metal complexes (TMCs) pose challenges in mapping out initial excited-state pathways that could influence photochemical outcomes. Ultrafast intersystem crossing (ISC) dynamics of four structurally related platinum(II) dimer complexes were examined by detecting their coherent vibrational wavepacket (CVWP) motions of Pt-Pt stretching mode in the metal-metal-to-ligand-charge-transfer excited states. Structurally dependent CVWP behaviors (frequency, dephasing time, and oscillation amplitudes) were captured by femtosecond transient absorption spectroscopy, analyzed by short-time Fourier transformation, and rationalized by quantum mechanical calculations, revealing dual ISC pathways. The results suggest that the ligands could fine-tune the PESs to influence the proximity of the conical intersections of the excited states with the Franck-Condon state and thus to control the branching ratio of the dual ISC pathways. This comparative study presents future opportunities in control excited-state trajectories of TMCs via ligand structures.
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Affiliation(s)
- Pyosang Kim
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Chemical Science and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Andrew J S Valentine
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Subhangi Roy
- Department of Chemistry, North Carolina State University, Raleigh, North Carolina 27695-8204, United States
| | - Alexis W Mills
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Arnab Chakraborty
- 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
| | - Xiaosong Li
- Department of Chemistry, University of Washington, Seattle, Washington 98195, United States
| | - Lin X Chen
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- Chemical Science and Engineering Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
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12
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Reichenauer F, Wang C, Förster C, Boden P, Ugur N, Báez-Cruz R, Kalmbach J, Carrella LM, Rentschler E, Ramanan C, Niedner-Schatteburg G, Gerhards M, Seitz M, Resch-Genger U, Heinze K. Strongly Red-Emissive Molecular Ruby [Cr(bpmp) 2] 3+ Surpasses [Ru(bpy) 3] 2. J Am Chem Soc 2021; 143:11843-11855. [PMID: 34296865 DOI: 10.1021/jacs.1c05971] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Gaining chemical control over the thermodynamics and kinetics of photoexcited states is paramount to an efficient and sustainable utilization of photoactive transition metal complexes in a plethora of technologies. In contrast to energies of charge transfer states described by spatially separated orbitals, the energies of spin-flip states cannot straightforwardly be predicted as Pauli repulsion and the nephelauxetic effect play key roles. Guided by multireference quantum chemical calculations, we report a novel highly luminescent spin-flip emitter with a quantum chemically predicted blue-shifted luminescence. The spin-flip emission band of the chromium complex [Cr(bpmp)2]3+ (bpmp = 2,6-bis(2-pyridylmethyl)pyridine) shifted to higher energy from ca. 780 nm observed for known highly emissive chromium(III) complexes to 709 nm. The photoluminescence quantum yields climb to 20%, and very long excited state lifetimes in the millisecond range are achieved at room temperature in acidic D2O solution. Partial ligand deuteration increases the quantum yield to 25%. The high excited state energy of [Cr(bpmp)2]3+ and its facile reduction to [Cr(bpmp)2]2+ result in a high excited state redox potential. The ligand's methylene bridge acts as a Brønsted acid quenching the luminescence at high pH. Combined with a pH-insensitive chromium(III) emitter, ratiometric optical pH sensing is achieved with single wavelength excitation. The photophysical and ground state properties (quantum yield, lifetime, redox potential, and acid/base) of this spin-flip complex incorporating an earth-abundant metal surpass those of the classical precious metal [Ru(α-diimine)3]2+ charge transfer complexes, which are commonly employed in optical sensing and photo(redox) catalysis, underlining the bright future of these molecular ruby analogues.
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Affiliation(s)
- Florian Reichenauer
- Department of Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Cui Wang
- Division Biophotonics, Federal Institute for Materials Research and Testing (BAM), Richard-Willstätter-Str. 11, 12489 Berlin, Germany.,Institut für Chemie und Biochemie, Freie Universität Berlin, Arnimallee 22, 14195 Berlin, Germany
| | - Christoph Förster
- Department of Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Pit Boden
- Department of Chemistry and Research Center Optimas, University Kaiserslautern, Erwin-Schrödinger-Straße, 67663 Kaiserslautern, Germany
| | - Naz Ugur
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Ricardo Báez-Cruz
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Jens Kalmbach
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Luca M Carrella
- Department of Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Eva Rentschler
- Department of Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
| | - Charusheela Ramanan
- Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany
| | - Gereon Niedner-Schatteburg
- Department of Chemistry and Research Center Optimas, University Kaiserslautern, Erwin-Schrödinger-Straße, 67663 Kaiserslautern, Germany
| | - Markus Gerhards
- Department of Chemistry and Research Center Optimas, University Kaiserslautern, Erwin-Schrödinger-Straße, 67663 Kaiserslautern, Germany
| | - Michael Seitz
- Institute of Inorganic Chemistry, University of Tübingen, Auf der Morgenstelle 18, 72076 Tübingen, Germany
| | - Ute Resch-Genger
- Division Biophotonics, Federal Institute for Materials Research and Testing (BAM), Richard-Willstätter-Str. 11, 12489 Berlin, Germany
| | - Katja Heinze
- Department of Chemistry, Johannes Gutenberg University of Mainz, Duesbergweg 10-14, 55128 Mainz, Germany
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13
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Head-Marsden K, Flick J, Ciccarino CJ, Narang P. Quantum Information and Algorithms for Correlated Quantum Matter. Chem Rev 2020; 121:3061-3120. [PMID: 33326218 DOI: 10.1021/acs.chemrev.0c00620] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Discoveries in quantum materials, which are characterized by the strongly quantum-mechanical nature of electrons and atoms, have revealed exotic properties that arise from correlations. It is the promise of quantum materials for quantum information science superimposed with the potential of new computational quantum algorithms to discover new quantum materials that inspires this Review. We anticipate that quantum materials to be discovered and developed in the next years will transform the areas of quantum information processing including communication, storage, and computing. Simultaneously, efforts toward developing new quantum algorithmic approaches for quantum simulation and advanced calculation methods for many-body quantum systems enable major advances toward functional quantum materials and their deployment. The advent of quantum computing brings new possibilities for eliminating the exponential complexity that has stymied simulation of correlated quantum systems on high-performance classical computers. Here, we review new algorithms and computational approaches to predict and understand the behavior of correlated quantum matter. The strongly interdisciplinary nature of the topics covered necessitates a common language to integrate ideas from these fields. We aim to provide this common language while weaving together fields across electronic structure theory, quantum electrodynamics, algorithm design, and open quantum systems. Our Review is timely in presenting the state-of-the-art in the field toward algorithms with nonexponential complexity for correlated quantum matter with applications in grand-challenge problems. Looking to the future, at the intersection of quantum information science and algorithms for correlated quantum matter, we envision seminal advances in predicting many-body quantum states and describing excitonic quantum matter and large-scale entangled states, a better understanding of high-temperature superconductivity, and quantifying open quantum system dynamics.
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Affiliation(s)
- Kade Head-Marsden
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Johannes Flick
- Center for Computational Quantum Physics, Flatiron Institute, New York, New York 10010, United States
| | - Christopher J Ciccarino
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States.,Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138, United States
| | - Prineha Narang
- John A. Paulson School of Engineering and Applied Sciences, Harvard University, Cambridge, Massachusetts 02138, United States
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14
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Fataftah MS, Bayliss SL, Laorenza DW, Wang X, Phelan BT, Wilson CB, Mintun PJ, Kovos BD, Wasielewski MR, Han S, Sherwin MS, Awschalom DD, Freedman DE. Trigonal Bipyramidal V 3+ Complex as an Optically Addressable Molecular Qubit Candidate. J Am Chem Soc 2020; 142:20400-20408. [PMID: 33210910 DOI: 10.1021/jacs.0c08986] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Synthetic chemistry enables a bottom-up approach to quantum information science, where atoms can be deterministically positioned in a quantum bit or qubit. Two key requirements to realize quantum technologies are qubit initialization and read-out. By imbuing molecular spins with optical initialization and readout mechanisms, analogous to solid-state defects, molecules could be integrated into existing quantum infrastructure. To mimic the electronic structure of optically addressable defect sites, we designed the spin-triplet, V3+ complex, (C6F5)3trenVCNtBu (1). We measured the static spin properties as well as the spin coherence time of 1 demonstrating coherent control of this spin qubit with a 240 GHz electron paramagnetic resonance spectrometer powered by a free electron laser. We found that 1 exhibited narrow, near-infrared photoluminescence (PL) from a spin-singlet excited state. Using variable magnetic field PL spectroscopy, we resolved emission into each of the ground-state spin sublevels, a crucial component for spin-selective optical initialization and readout. This work demonstrates that trigonally symmetric, heteroleptic V3+ complexes are candidates for optical spin addressability.
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Affiliation(s)
- Majed S Fataftah
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Sam L Bayliss
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Daniel W Laorenza
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
| | - Xiaoling Wang
- Institute for Terahertz Science and Technology, University of California, Santa Barbara, Santa Barbara, California 93106, United States
- Department of Physics, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Brian T Phelan
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- The Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208, United States
| | - C Blake Wilson
- Institute for Terahertz Science and Technology, University of California, Santa Barbara, Santa Barbara, California 93106, United States
- Department of Physics, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Peter J Mintun
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Berk D Kovos
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
| | - Michael R Wasielewski
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
- The Institute for Sustainability and Energy at Northwestern, Northwestern University, Evanston, Illinois 60208, United States
| | - Songi Han
- Department of Chemical Engineering, University of California, Santa Barbara, Santa Barbara, California 93106, United States
- Department of Chemistry and Biochemistry, University of California, Santa Barbara, Santa Barbara, California 93106, United States
- Institute for Terahertz Science and Technology, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - Mark S Sherwin
- Institute for Terahertz Science and Technology, University of California, Santa Barbara, Santa Barbara, California 93106, United States
- Department of Physics, University of California, Santa Barbara, Santa Barbara, California 93106, United States
| | - David D Awschalom
- Pritzker School of Molecular Engineering, University of Chicago, Chicago, Illinois 60637, United States
- Department of Physics, University of Chicago, Chicago, Illinois 60637, United States
- Center for Molecular Engineering and Materials Science Division, Argonne National Laboratory, Lemont, Illinois 60439, United States
| | - Danna E Freedman
- Department of Chemistry, Northwestern University, Evanston, Illinois 60208, United States
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15
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Wasielewski MR, Forbes MDE, Frank NL, Kowalski K, Scholes GD, Yuen-Zhou J, Baldo MA, Freedman DE, Goldsmith RH, Goodson T, Kirk ML, McCusker JK, Ogilvie JP, Shultz DA, Stoll S, Whaley KB. Exploiting chemistry and molecular systems for quantum information science. Nat Rev Chem 2020; 4:490-504. [PMID: 37127960 DOI: 10.1038/s41570-020-0200-5] [Citation(s) in RCA: 188] [Impact Index Per Article: 47.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/27/2020] [Indexed: 12/21/2022]
Abstract
The power of chemistry to prepare new molecules and materials has driven the quest for new approaches to solve problems having global societal impact, such as in renewable energy, healthcare and information science. In the latter case, the intrinsic quantum nature of the electronic, nuclear and spin degrees of freedom in molecules offers intriguing new possibilities to advance the emerging field of quantum information science. In this Perspective, which resulted from discussions by the co-authors at a US Department of Energy workshop held in November 2018, we discuss how chemical systems and reactions can impact quantum computing, communication and sensing. Hierarchical molecular design and synthesis, from small molecules to supramolecular assemblies, combined with new spectroscopic probes of quantum coherence and theoretical modelling of complex systems, offer a broad range of possibilities to realize practical quantum information science applications.
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Affiliation(s)
| | - Malcolm D E Forbes
- Department of Chemistry, Bowling Green State University, Bowling Green, OH, USA
| | - Natia L Frank
- Department of Chemistry, University of Nevada-Reno, Reno, Nevada, USA
| | - Karol Kowalski
- Pacific Northwest National Laboratory, Richland, WA, USA
| | | | - Joel Yuen-Zhou
- Department of Chemistry & Biochemistry, University of California, San Diego, La Jolla, CA, USA
| | - Marc A Baldo
- Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Danna E Freedman
- Department of Chemistry, Northwestern University, Evanston, IL, USA
| | | | - Theodore Goodson
- Department of Chemistry, University of Michigan, Ann Arbor, MI, USA
| | - Martin L Kirk
- Department of Chemistry and Chemical Biology, University of New Mexico, Albuquerque, NM, USA
| | - James K McCusker
- Department of Chemistry, Michigan State University, East Lansing, MI, USA
| | | | - David A Shultz
- Department of Chemistry, North Carolina State University, Raleigh, NC, USA
| | - Stefan Stoll
- Department of Chemistry, University of Washington, Seattle, WA, USA
| | - K Birgitta Whaley
- Department of Chemistry, University of California, Berkeley, CA, USA
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16
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Hart SM, Banal JL, Bathe M, Schlau-Cohen GS. Identification of Nonradiative Decay Pathways in Cy3. J Phys Chem Lett 2020; 11:5000-5007. [PMID: 32484350 DOI: 10.1021/acs.jpclett.0c01201] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Photoexcited fluorescent markers are extensively used in spectroscopy, imaging, and analysis of biological systems. The performance of fluorescent markers depends on high levels of emission, which are limited by competing nonradiative decay pathways. Small-molecule fluorescent dyes have been increasingly used as markers due to their high and stable emission. Despite their prevalence, the nonradiative decay pathways of these dyes have not been determined. Here, we investigate these pathways for a widely used indocarbocyanine dye, Cy3, using transient grating spectroscopy. We identify a nonradiative decay pathway via a previously unknown dark state formed within ∼1 ps of photoexcitation. Our experiments, in combination with electronic structure calculations, suggest that the generation of the dark state is mediated by picosecond vibrational mode coupling, likely via a conical intersection. We further identify the vibrational modes, and thus structural elements, responsible for the formation and dynamics of the dark state, providing insight into suppressing nonradiative decay pathways in fluorescent markers such as Cy3.
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Affiliation(s)
- Stephanie M Hart
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - James L Banal
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Mark Bathe
- Department of Biological Engineering, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
| | - Gabriela S Schlau-Cohen
- Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, United States
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17
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Collet E. Ultrafast control of anisotropy. Nat Chem 2020; 12:429-430. [DOI: 10.1038/s41557-020-0462-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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18
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Khvorost TA, Beliaev LY, Potalueva E, Laptenkova AV, Selyutin AA, Bogachev NA, Skripkin MY, Ryazantsev MN, Tkachenko N, Mereshchenko AS. Ultrafast Photochemistry of the [Cr(NCS)6]3– Complex in Dimethyl Sulfoxide and Dimethylformamide upon Excitation into Ligand-Field Electronic State. J Phys Chem B 2020; 124:3724-3733. [DOI: 10.1021/acs.jpcb.0c00088] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Taras A. Khvorost
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Leonid Yu. Beliaev
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Ekaterina Potalueva
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Anastasia V. Laptenkova
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Artem A. Selyutin
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Nikita A. Bogachev
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Mikhail Yu. Skripkin
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
| | - Mikhail N. Ryazantsev
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
- Saint Petersburg Academic University, ul. Khlopina 8/3, St. Petersburg, 194021, Russia
| | - Nikolai Tkachenko
- Chemistry and Advanced Materials Group, Faculty of Engineering and Natural Sciences, Tampere University, Korkeakoulunkatu 8, FI-33720 Tampere, Finland
| | - Andrey S. Mereshchenko
- Saint-Petersburg State University, 7/9 Universitetskaya nab., St. Petersburg, 199034, Russia
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19
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Liedy F, Eng J, McNab R, Inglis R, Penfold TJ, Brechin EK, Johansson JO. Vibrational coherences in manganese single-molecule magnets after ultrafast photoexcitation. Nat Chem 2020; 12:452-458. [PMID: 32123341 DOI: 10.1038/s41557-020-0431-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2018] [Accepted: 01/27/2020] [Indexed: 11/09/2022]
Abstract
Magnetic recording using femtosecond laser pulses has recently been achieved in some dielectric media, showing potential for ultrafast data storage applications. Single-molecule magnets (SMMs) are metal complexes with two degenerate magnetic ground states and are promising for increasing storage density, but remain unexplored using ultrafast techniques. Here we have explored the dynamics occurring after photoexcitation of a trinuclear µ3-oxo-bridged Mn(III)-based SMM, whose magnetic anisotropy is closely related to the Jahn-Teller distortion. Ultrafast transient absorption spectroscopy in solution reveals oscillations superimposed on the decay traces due to a vibrational wavepacket. Based on complementary measurements and calculations on the monomer Mn(acac)3, we conclude that the wavepacket motion in the trinuclear SMM is constrained along the Jahn-Teller axis due to the µ3-oxo and µ-oxime bridges. Our results provide new possibilities for optical control of the magnetization in SMMs on femtosecond timescales and open up new molecular-design challenges to control the wavepacket motion in the excited state of polynuclear transition-metal complexes.
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Affiliation(s)
- Florian Liedy
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK
| | - Julien Eng
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Robbie McNab
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK
| | - Ross Inglis
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK
| | - Thomas J Penfold
- Chemistry, School of Natural and Environmental Sciences, Newcastle University, Newcastle upon Tyne, UK
| | - Euan K Brechin
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK
| | - J Olof Johansson
- EaStCHEM School of Chemistry, University of Edinburgh, Edinburgh, UK.
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20
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Kim J, Kang DG, Kim SK, Joo T. Role of coherent nuclear motion in the ultrafast intersystem crossing of ruthenium complexes. Phys Chem Chem Phys 2020; 22:25811-25818. [DOI: 10.1039/d0cp05368f] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Ultrafast intersystem crossing (ISC) of ruthenium complexes is time-resolved directly. Coherent nuclear wave packets suggest that metal–ligand stretching or symmetry breaking vibrational modes are strongly coupled with the ISC.
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Affiliation(s)
- JunWoo Kim
- Department of Chemistry
- Pohang University of Science and Technology (POSTECH)
- Pohang 37673
- Korea
| | | | | | - Taiha Joo
- Department of Chemistry
- Pohang University of Science and Technology (POSTECH)
- Pohang 37673
- Korea
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21
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Mai S, González L. Unconventional two-step spin relaxation dynamics of [Re(CO) 3(im)(phen)] + in aqueous solution. Chem Sci 2019; 10:10405-10411. [PMID: 32110331 PMCID: PMC6988600 DOI: 10.1039/c9sc03671g] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2019] [Accepted: 09/19/2019] [Indexed: 12/12/2022] Open
Abstract
Changes of molecular spin are ubiquitous in chemistry and biology. Among spin flip processes, one of the fastest is intersystem crossing (ISC) in transition metal complexes. Here, we investigate the spin relaxation dynamics and emission spectrum of [Re(CO)3(im)(phen)]+ (im = imidazole, phen = phenanthroline) using extensive full-dimensional excited-state dynamics simulations in explicit aqueous solution. Contrary to what has been observed in other transition metal complexes, the transition from the singlet to triplet states occurs via a two-step process, with clearly separable electronic and nuclear-driven components with two different time scales. The initially excited electronic wave function is a "molecular spin-orbit wave packet" that evolves almost instantaneously, with an 8 fs time constant, into an approximate 25 : 75 singlet-to-triplet equilibrium. Surprisingly, this ISC process is an order of magnitude faster than it was previously documented for this and other rhenium(i) carbonyl diimine complexes from emission spectra. Simulations including explicit laser field interactions evidence that few-cycle UV laser pulses are required to follow the creation and evolution of such molecular spin-orbit wave packets. The analysis of the dynamics also reveals a retarded ISC component, with a time constant of 420 fs, which can be explained invoking intramolecular vibrational energy redistribution. The emission spectrum is shown to be characterized by ISC convoluted with internal conversion and vibrational relaxation. These results provide fundamental understanding of ultrafast intersystem crossing in transition metal complexes.
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Affiliation(s)
- Sebastian Mai
- Institute of Theoretical Chemistry , Faculty of Chemistry , University of Vienna , Währinger Straße 17 , 1090 Vienna , Austria .
| | - Leticia González
- Institute of Theoretical Chemistry , Faculty of Chemistry , University of Vienna , Währinger Straße 17 , 1090 Vienna , Austria .
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22
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Matveev SM, Budkina DS, Zheldakov IL, Phelan MR, Hicks CM, Tarnovsky AN. Femtosecond dynamics of metal-centered and ligand-to-metal charge-transfer (t2g-based) electronic excited states in various solvents: A comprehensive study of IrBr62−. J Chem Phys 2019; 150:054302. [DOI: 10.1063/1.5079754] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Affiliation(s)
- Sergey M. Matveev
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University,Bowling Green, Ohio 43403, USA
| | - Darya S. Budkina
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University,Bowling Green, Ohio 43403, USA
| | - Igor L. Zheldakov
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University,Bowling Green, Ohio 43403, USA
| | - Michael R. Phelan
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University,Bowling Green, Ohio 43403, USA
| | - Christopher M. Hicks
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University,Bowling Green, Ohio 43403, USA
| | - Alexander N. Tarnovsky
- Department of Chemistry and the Center for Photochemical Sciences, Bowling Green State University,Bowling Green, Ohio 43403, USA
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23
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24
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McCusker JK. Electronic structure in the transition metal block and its implications for light harvesting. Science 2019; 363:484-488. [PMID: 30705184 DOI: 10.1126/science.aav9104] [Citation(s) in RCA: 171] [Impact Index Per Article: 34.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Transition metal-based chromophores play a central role in a variety of light-enabled chemical processes ranging from artificial solar energy conversion to photoredox catalysis. The most commonly used compounds include elements from the second and third transition series (e.g., ruthenium and iridium), but their Earth-abundant first-row analogs fail to engage in photoinduced electron transfer chemistry despite having virtually identical absorptive properties. This disparate behavior stems from fundamental differences in the nature of 3d versus 4d and 5d orbitals, resulting in an inversion in the compounds' excited-state electronic structure and undermining the ability of compounds with first-row elements to engage in photoinduced electron transfer. This Review will survey the key experimental observations establishing this difference in behavior, discuss the underlying reasons for this phenomenon, and briefly summarize efforts that are currently under way to alter this paradigm and open the door to new opportunities for using Earth-abundant materials for photoinduced electron transfer chemistries.
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Affiliation(s)
- James K McCusker
- Department of Chemistry, Michigan State University, East Lansing, MI 48824, USA
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25
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Ling F, Li S, Wang Y, Wang P, Zhang B. Vibrational coherence in the composition-selected wavepacket of photoexcited pyrimidine. J Chem Phys 2019; 150:044308. [DOI: 10.1063/1.5083681] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Fengzi Ling
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Shuai Li
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Yanmei Wang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
| | - Pengfei Wang
- Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen 518060, China
| | - Bing Zhang
- State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, China
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26
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Fataftah MS, Freedman DE. Progress towards creating optically addressable molecular qubits. Chem Commun (Camb) 2018; 54:13773-13781. [PMID: 30468437 DOI: 10.1039/c8cc07939k] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The emerging field of quantum information science promises to transform a diverse range of scientific fields, ranging from computation to sensing and metrology. The interdisciplinary scientific community laid the groundwork for the next generation of quantum technologies through key advances in understanding the fundamental unit of quantum information science, the qubit. Electronic spin is a promising platform for qubits, demonstrating suitably long coherence times, optical initialization, and single spin addressability. Herein, we discuss recent accomplishments and future progress from our group targeted at imbuing transition metal complexes with the aforementioned properties, creating a pathway to fusing spatial precision with long coherence times. A strong emphasis of this feature article is progressing towards single spin measurements via a chemical approach for imbuing molecular qubits with an optically-induced spin polarization mechanism.
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Affiliation(s)
- Majed S Fataftah
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA.
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Brown AM, McCusker CE, Carey MC, Blanco-Rodríguez AM, Towrie M, Clark IP, Vlček A, McCusker JK. Vibrational Relaxation and Redistribution Dynamics in Ruthenium(II) Polypyridyl-Based Charge-Transfer Excited States: A Combined Ultrafast Electronic and Infrared Absorption Study. J Phys Chem A 2018; 122:7941-7953. [DOI: 10.1021/acs.jpca.8b06197] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Allison M. Brown
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Catherine E. McCusker
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Monica C. Carey
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
| | - Ana Maria Blanco-Rodríguez
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
| | - Michael Towrie
- Central Laser Facility, Research Complex at Harwell, STFC, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Ian P. Clark
- Central Laser Facility, Research Complex at Harwell, STFC, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, Oxfordshire OX11 0QX, United Kingdom
| | - Antonín Vlček
- School of Biological and Chemical Sciences, Queen Mary University of London, Mile End Road, London E1 4NS, United Kingdom
- J. Heyrovsky Institute of Physical Chemistry, Academy of Sciences of the Czech Republic, Dolejskova 3, CZ-182 23 Prague, Czech Republic
| | - James K. McCusker
- Department of Chemistry, Michigan State University, East Lansing, Michigan 48824, United States
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28
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Matveeva SG, Shushakov AA, Pozdnyakov IP, Grivin VP, Plyusnin VF, Vasilchenko DB, Zadesenets AV, Melnikov AA, Chekalin SV, Glebov EM. A cis,fac-[RuCl 2(DMSO) 3(H 2O)] complex exhibits ultrafast photochemical aquation/rearrangement. Photochem Photobiol Sci 2018; 17:1222-1228. [PMID: 30070288 DOI: 10.1039/c8pp00232k] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
It is known that both cis,fac-[RuCl2(DMSO)3(H2O)] (1a) and trans,cis,cis-[RuCl2(DMSO)2(H2O)2] (2a) complexes, which are formed on the dissolution of trans and cis-isomers of [RuCl2(DMSO)4] in water, demonstrate light-induced anticancer activity. The first stage of 1a photochemistry is its transformation to 2a occurring with a rather high quantum yield, 0.64 ± 0.17. The mechanism of the 1a → 2a phototransformation was studied by means of nanosecond laser flash photolysis and ultrafast pump-probe spectroscopy. The reaction occurs in the picosecond time range via the formation and decay of two successive intermediates interpreted as Ru(ii) complexes with different sets of ligands. A tentative mechanism of phototransformation is proposed.
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Affiliation(s)
- Svetlana G Matveeva
- Voevodsky Institute of Chemical Kinetics and Combustion, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation.
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29
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Vibrational coherence transfer in the ultrafast intersystem crossing of a diplatinum complex in solution. Proc Natl Acad Sci U S A 2018; 115:E6396-E6403. [PMID: 29941568 DOI: 10.1073/pnas.1719899115] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
We investigate the ultrafast transient absorption response of tetrakis(μ-pyrophosphito)diplatinate(II), [Pt2(μ-P2O5H2)4]4- [hereafter abbreviated Pt(pop)], in acetonitrile upon excitation of its lowest singlet 1A2u state. Compared with previously reported solvents [van der Veen RM, Cannizzo A, van Mourik F, Vlček A, Jr, Chergui M (2011) J Am Chem Soc 133:305-315], a significant shortening of the intersystem crossing (ISC) time (<1 ps) from the lowest singlet to the lowest triplet state is found, allowing for a transfer of vibrational coherence, observed in the course of an ISC in a polyatomic molecule in solution. Density functional theory (DFT) quantum mechanical/molecular mechanical (QM/MM) simulations of Pt(pop) in acetonitrile and ethanol show that high-lying, mostly triplet, states are strongly mixed and shifted to lower energies due to interactions with the solvent, providing an intermediate state (or manifold of states) for the ISC. This suggests that the larger the solvation energies of the intermediate state(s), the shorter the ISC time. Because the latter is smaller than the pure dephasing time of the vibrational wave packet, coherence is conserved during the spin transition. These results underscore the crucial role of the solvent in directing pathways of intramolecular energy flow.
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31
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Cadranel A, Oviedo PS, Alborés P, Baraldo LM, Guldi DM, Hodak JH. Electronic Energy Transduction from {Ru(py) 4} Chromophores to Cr(III) Luminophores. Inorg Chem 2018; 57:3042-3053. [PMID: 29473740 DOI: 10.1021/acs.inorgchem.7b02799] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Despite the large body of work on {Ru(bpy)2} sensitizer fragments, the same attention has not been devoted to their {Ru(py)4} analogues. In this context, we explored the donor-acceptor trans-[Ru(L)4{(μ-NC)Cr(CN)5}2]4-, where L = pyridine, 4-methoxypyridine, 4-dimethylaminopyridine. We report on the synthesis and the crystal structure as well as the electrochemical, spectroscopical, and photophysical properties of these trimetallic complexes, including transient absorption measurements. We observed emission from chromium-centered d-d states upon illuminating into either MLCT or MM'CT absorptions of {Ru(L)4} or {Ru-Cr}, respectively. The underlying energy transfer is as fast as 600 fs with quantum efficiencies ranging from 10% to 100%. These results document that {Ru(py)4} sensitizer fragments are as efficient as {Ru(bpy)2} in short-range energy transfer scenarios.
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Affiliation(s)
- Alejandro Cadranel
- Departamento de Química Analítica, Inorgánica y Química Física & INQUIMAE, Facultad de Ciencias Exactas y Naturales , Universidad de Buenos Aires , Pabellón 2 , Ciudad Universitaria, C1428EHA Buenos Aires , Argentina.,Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 1-3 , 91058 Erlangen , Germany
| | - Paola S Oviedo
- Departamento de Química Analítica, Inorgánica y Química Física & INQUIMAE, Facultad de Ciencias Exactas y Naturales , Universidad de Buenos Aires , Pabellón 2 , Ciudad Universitaria, C1428EHA Buenos Aires , Argentina
| | - Pablo Alborés
- Departamento de Química Analítica, Inorgánica y Química Física & INQUIMAE, Facultad de Ciencias Exactas y Naturales , Universidad de Buenos Aires , Pabellón 2 , Ciudad Universitaria, C1428EHA Buenos Aires , Argentina
| | - Luis M Baraldo
- Departamento de Química Analítica, Inorgánica y Química Física & INQUIMAE, Facultad de Ciencias Exactas y Naturales , Universidad de Buenos Aires , Pabellón 2 , Ciudad Universitaria, C1428EHA Buenos Aires , Argentina
| | - Dirk M Guldi
- Department of Chemistry and Pharmacy & Interdisciplinary Center for Molecular Materials (ICMM) , Friedrich-Alexander-Universität Erlangen-Nürnberg , Egerlandstraße 1-3 , 91058 Erlangen , Germany
| | - José H Hodak
- Departamento de Química Analítica, Inorgánica y Química Física & INQUIMAE, Facultad de Ciencias Exactas y Naturales , Universidad de Buenos Aires , Pabellón 2 , Ciudad Universitaria, C1428EHA Buenos Aires , Argentina
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32
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Cheng CH, Wang WZ, Peng SM, Chen IC. Excited state dynamics of symmetric and asymmetric Cr 3(dpa) 4Cl 2 measured using femtosecond transient absorption spectroscopy. Phys Chem Chem Phys 2018; 19:25471-25477. [PMID: 28900646 DOI: 10.1039/c7cp03968a] [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
Herein, the excited-state dynamics of an extended metal atom chain complex, Cr3(dpa)4Cl2 (dpa = dipyridylamide), in tetrahydrofuran solution were investigated using femtosecond transient absorption spectroscopy. Upon excitation at a wavelength of 330 nm, two distinct excited-state absorption species with varied dynamics were identified and assigned to the symmetric (s-) and unsymmetric (u-) Cr3(dpa)4Cl2. The major species is s-Cr3(dpa)4Cl2 that undergoes rapid conversion at less than 100 fs from the ligand-centred π-π* state, which is the initially accessed state, to the metal-centred d-d state and then vibrational cooling accompanying the structural relaxation at a time constant ∼2.2 ps. Most of the s-form is recovered to the ground state at ∼200 ps. For u-Cr3(dpa)4Cl2, a similar rapid conversion to d-d states is observed, and the geometric/vibrational relaxation is ∼0.8 ps. The second recovery of the ground state with approximately equal amplitude is observed at a time constant of ∼5 ns. This might be because many d-d states exist and about half of them inefficiently couple with the ground state surface.
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Affiliation(s)
- Chao-Han Cheng
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan 30013, Republic of China.
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33
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Rogozina MV, Yudanov VV, Fedunov RG, Pozdnyakov IP, Melnikov AA, Chekalin SV, Glebov EM. Short-lived intermediates in photochemistry of an OsCl62− complex in aqueous solutions. Photochem Photobiol Sci 2018; 17:18-26. [DOI: 10.1039/c7pp00299h] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photoaquation of an OsIVCl62− complex occurs via a pentacoordinated OsIVCl5− intermediate.
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Affiliation(s)
- Marina V. Rogozina
- Voevodsky Institute of Chemical Kinetics and Combustion
- Novosibirsk
- Russian Federation
- Vologograd State University
- Volgograd
| | - Vladislav V. Yudanov
- Voevodsky Institute of Chemical Kinetics and Combustion
- Novosibirsk
- Russian Federation
- Vologograd State University
- Volgograd
| | | | - Ivan P. Pozdnyakov
- Voevodsky Institute of Chemical Kinetics and Combustion
- Novosibirsk
- Russian Federation
- Novosibirsk State University
- Novosibirsk
| | - Alexey A. Melnikov
- Institute of Spectroscopy
- Russian Academy of Sciences
- 119333 Troitsk, Moscow
- Russian Federation
| | - Sergey V. Chekalin
- Institute of Spectroscopy
- Russian Academy of Sciences
- 119333 Troitsk, Moscow
- Russian Federation
| | - Evgeni M. Glebov
- Voevodsky Institute of Chemical Kinetics and Combustion
- Novosibirsk
- Russian Federation
- Novosibirsk State University
- Novosibirsk
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34
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Hedley L, Horbury MD, Liedy F, Johansson JO. Observation of excited state absorption in the V-Cr Prussian blue analogue. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.08.070] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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35
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Glebov EM, Pozdnyakov IP, Matveeva SG, Melnikov AA, Chekalin SV, Rogozina MV, Yudanov VV, Grivin VP, Plyusnin VF. Primary photophysical and photochemical processes for hexachloroosmate(iv) in aqueous solution. Photochem Photobiol Sci 2017; 16:220-227. [PMID: 28009886 DOI: 10.1039/c6pp00382f] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The photoaquation of the OsIVCl62- complex was studied by means of stationary photolysis, nanosecond laser flash photolysis and ultrafast kinetic spectroscopy. The OsIVCl5(OH)2- complex was found to be the only reaction product. The quantum yield of photoaquation is rather low and wavelength-dependent. No impact of redox processes on photoaquation was revealed. The total characteristic lifetime of the process is about 80 ps. Three intermediates were recorded in the femto- and picosecond time domains and assigned to different Os(iv) species. The nature of intermediates and possible mechanisms of photoaquation are discussed.
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Affiliation(s)
- Evgeni M Glebov
- Voevodsky Institute of Chemical Kinetics and Combustion, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation. and Novosibirsk State University, 2 Pirogova Str., 630090, Novosibirsk, Russian Federation
| | - Ivan P Pozdnyakov
- Voevodsky Institute of Chemical Kinetics and Combustion, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation. and Novosibirsk State University, 2 Pirogova Str., 630090, Novosibirsk, Russian Federation
| | - Svetlana G Matveeva
- Voevodsky Institute of Chemical Kinetics and Combustion, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation.
| | - Alexei A Melnikov
- Institute of Spectroscopy, Russian Academy of Sciences, 5 Fizicheskaya Str., 119333 Troitsk, Moscow, Russian Federation.
| | - Sergey V Chekalin
- Institute of Spectroscopy, Russian Academy of Sciences, 5 Fizicheskaya Str., 119333 Troitsk, Moscow, Russian Federation.
| | - Marina V Rogozina
- Voevodsky Institute of Chemical Kinetics and Combustion, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation. and Vologograd State University, 100 University Ave., 400062, Volgograd, Russian Federation.
| | - Vladislav V Yudanov
- Voevodsky Institute of Chemical Kinetics and Combustion, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation. and Vologograd State University, 100 University Ave., 400062, Volgograd, Russian Federation.
| | - Vjacheslav P Grivin
- Voevodsky Institute of Chemical Kinetics and Combustion, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation.
| | - Victor F Plyusnin
- Voevodsky Institute of Chemical Kinetics and Combustion, 3 Institutskaya Str., 630090, Novosibirsk, Russian Federation. and Novosibirsk State University, 2 Pirogova Str., 630090, Novosibirsk, Russian Federation
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36
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Whittemore TJ, Sayre HJ, Xue C, White TA, Gallucci JC, Turro C. New Rh2(II,II) Complexes for Solar Energy Applications: Panchromatic Absorption and Excited-State Reactivity. J Am Chem Soc 2017; 139:14724-14732. [DOI: 10.1021/jacs.7b08489] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Tyler J. Whittemore
- Department of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Hannah J. Sayre
- Department of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Congcong Xue
- Department of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Travis A. White
- Department of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Judith C. Gallucci
- Department of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Claudia Turro
- Department of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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37
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Conservation of vibrational coherence in ultrafast electronic relaxation: The case of diplatinum complexes in solution. Chem Phys Lett 2017. [DOI: 10.1016/j.cplett.2017.02.071] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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38
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39
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Delor M, Archer SA, Keane T, Meijer AJHM, Sazanovich IV, Greetham GM, Towrie M, Weinstein JA. Directing the path of light-induced electron transfer at a molecular fork using vibrational excitation. Nat Chem 2017; 9:1099-1104. [DOI: 10.1038/nchem.2793] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2016] [Accepted: 05/05/2017] [Indexed: 11/09/2022]
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40
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Otto S, Nauth AM, Ermilov E, Scholz N, Friedrich A, Resch-Genger U, Lochbrunner S, Opatz T, Heinze K. Photo-Chromium: Sensitizer for Visible-Light-Induced Oxidative C−H Bond Functionalization-Electron or Energy Transfer? CHEMPHOTOCHEM 2017. [DOI: 10.1002/cptc.201700077] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Affiliation(s)
- Sven Otto
- Institute of Inorganic and Analytical Chemistry; Johannes Gutenberg University of Mainz; Duesbergweg 10-14 55128 Mainz Germany
- Graduate School Materials Science in Mainz; Staudingerweg 9 55128 Mainz Germany
| | - Alexander M. Nauth
- Institute of Organic Chemistry; Johannes Gutenberg University of Mainz; Duesbergweg 10-14 55128 Mainz Germany
| | - Eugenyi Ermilov
- Division 1.10; Federal Institute for Materials Research and Testing (BAM); Richard-Willstätter-Str. 11 12489 Berlin Germany
| | - Norman Scholz
- Division 1.10; Federal Institute for Materials Research and Testing (BAM); Richard-Willstätter-Str. 11 12489 Berlin Germany
| | - Aleksej Friedrich
- Institute of Physics, University of Rostock; Albert-Einstein-Str. 23 18059 Rostock Germany
| | - Ute Resch-Genger
- Division 1.10; Federal Institute for Materials Research and Testing (BAM); Richard-Willstätter-Str. 11 12489 Berlin Germany
| | - Stefan Lochbrunner
- Institute of Physics, University of Rostock; Albert-Einstein-Str. 23 18059 Rostock Germany
| | - Till Opatz
- Institute of Organic Chemistry; Johannes Gutenberg University of Mainz; Duesbergweg 10-14 55128 Mainz Germany
| | - Katja Heinze
- Institute of Inorganic and Analytical Chemistry; Johannes Gutenberg University of Mainz; Duesbergweg 10-14 55128 Mainz Germany
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41
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Using coherence to enhance function in chemical and biophysical systems. Nature 2017; 543:647-656. [DOI: 10.1038/nature21425] [Citation(s) in RCA: 398] [Impact Index Per Article: 56.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2016] [Accepted: 12/07/2016] [Indexed: 12/23/2022]
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42
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Stevenson SM, Higgins RF, Shores MP, Ferreira EM. Chromium photocatalysis: accessing structural complements to Diels-Alder adducts with electron-deficient dienophiles. Chem Sci 2017; 8:654-660. [PMID: 28451213 PMCID: PMC5297334 DOI: 10.1039/c6sc03303b] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2016] [Accepted: 09/11/2016] [Indexed: 12/29/2022] Open
Abstract
A chromium-catalyzed, visible light-activated net [4 + 2] cycloaddition between dienes and electron-deficient alkenes is described. Gathered evidence, via control experiments, isolated intermediates, and measured redox potentials, points to several converging reaction pathways that afford the cyclohexene adducts, including a photochemical [2 + 2] cycloaddition/vinylcyclobutane rearrangement cascade and a substrate excitation/oxidation sequence to a radical cation intermediate. Notably, the accompanying mechanistic stipulations result in a process that yields regioisomeric compounds from those generated by traditional Diels-Alder cycloadditions.
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Affiliation(s)
- Susan M Stevenson
- Department of Chemistry , University of Georgia , Athens , GA 30602 , USA .
| | - Robert F Higgins
- Department of Chemistry , Colorado State University , Fort Collins , CO 80523 , USA
| | - Matthew P Shores
- Department of Chemistry , Colorado State University , Fort Collins , CO 80523 , USA
| | - Eric M Ferreira
- Department of Chemistry , University of Georgia , Athens , GA 30602 , USA .
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43
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Shelby ML, Lestrange PJ, Jackson NE, Haldrup K, Mara MW, Stickrath AB, Zhu D, Lemke H, Chollet M, Hoffman BM, Li X, Chen LX. Ultrafast Excited State Relaxation of a Metalloporphyrin Revealed by Femtosecond X-ray Absorption Spectroscopy. J Am Chem Soc 2016; 138:8752-64. [PMID: 27286410 PMCID: PMC5074555 DOI: 10.1021/jacs.6b02176] [Citation(s) in RCA: 70] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Photoexcited Nickel(II) tetramesitylporphyrin (NiTMP), like many open-shell metalloporphyrins, relaxes rapidly through multiple electronic states following an initial porphyrin-based excitation, some involving metal centered electronic configuration changes that could be harnessed catalytically before excited state relaxation. While a NiTMP excited state present at 100 ps was previously identified by X-ray transient absorption (XTA) spectroscopy at a synchrotron source as a relaxed (d,d) state, the lowest energy excited state (J. Am. Chem. Soc., 2007, 129, 9616 and Chem. Sci., 2010, 1, 642), structural dynamics before thermalization were not resolved due to the ∼100 ps duration of the available X-ray probe pulse. Using the femtosecond (fs) X-ray pulses of the Linac Coherent Light Source (LCLS), the Ni center electronic configuration from the initial excited state to the relaxed (d,d) state has been obtained via ultrafast Ni K-edge XANES (X-ray absorption near edge structure) on a time scale from hundreds of femtoseconds to 100 ps. This enabled the identification of a short-lived Ni(I) species aided by time-dependent density functional theory (TDDFT) methods. Computed electronic and nuclear structure for critical excited electronic states in the relaxation pathway characterize the dependence of the complex's geometry on the electron occupation of the 3d orbitals. Calculated XANES transitions for these excited states assign a short-lived transient signal to the spectroscopic signature of the Ni(I) species, resulting from intramolecular charge transfer on a time scale that has eluded previous synchrotron studies. These combined results enable us to examine the excited state structural dynamics of NiTMP prior to thermal relaxation and to capture intermediates of potential photocatalytic significance.
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Affiliation(s)
- Megan L. Shelby
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60439, USA
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | | | - Nicholas E. Jackson
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60439, USA
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Kristoffer Haldrup
- Physics Department, Technical University of Denmark, 2800 Kgs. Lyngby, Denmark
| | - Michael W. Mara
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60439, USA
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Andrew B. Stickrath
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60439, USA
| | - Diling Zhu
- LCLS, SLAC National Laboratory, Menlo Park, California 94025, USA
| | - Henrik Lemke
- LCLS, SLAC National Laboratory, Menlo Park, California 94025, USA
| | - Matthieu Chollet
- LCLS, SLAC National Laboratory, Menlo Park, California 94025, USA
| | - Brian M. Hoffman
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
| | - Xiaosong Li
- Department of Chemistry, University of Washington, Seattle, WA 98195, USA
| | - Lin X. Chen
- Chemical Sciences and Engineering Division, Argonne National Laboratory, Lemont, IL 60439, USA
- Department of Chemistry, Northwestern University, Evanston, IL 60208, USA
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44
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Ford PC. From curiosity to applications. A personal perspective on inorganic photochemistry. Chem Sci 2016; 7:2964-2986. [PMID: 29997786 PMCID: PMC6003602 DOI: 10.1039/c6sc00188b] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2016] [Accepted: 02/12/2016] [Indexed: 02/06/2023] Open
Abstract
Over the past several decades, the photochemistry and photophysics of transition metal compounds has blossomed from a relatively niche topic to a major research theme. Applications arising from the elucidation of the fundamental principles defining this field now range from probing the rates and mechanisms of small molecules with metalloproteins to light activated molecular machines. Offered here is a personal perspective of metal complex photochemistry drawn from this author's long involvement with this field. Several examples are described. Topics include characterizing key excited states and tuning these to modify chemical reactivity and/or photoluminescence properties, as well as using photoreactions as an entry to reactive intermediates relevant to homogeneous catalysts. This is followed by discussions of applying these concepts to developing precursors and precursor-antenna conjugates for the photochemical delivery of small molecule bioregulators to physiological targets.
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Affiliation(s)
- Peter C Ford
- Department of Chemistry and Biochemistry , University of California , Santa Barbara , CA 93110-9510 , USA .
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45
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Song P, Li Y, Ma F, Pullerits T, Sun M. Photoinduced Electron Transfer in Organic Solar Cells. CHEM REC 2016; 16:734-53. [PMID: 26853631 DOI: 10.1002/tcr.201500244] [Citation(s) in RCA: 44] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2012] [Indexed: 11/07/2022]
Abstract
Electron transfer (ET) is the key process in light-driven charge separation reactions in organic solar cells. The current review summarizes the progress in theoretical modelling of ET in these materials. First we give an account of ET, with a description originating from Marcus theory. We systematically go through all the relevant parameters and show how they depend on different material properties, and discuss the consequences such dependencies have for the performance of the devices. Finally, we present a set of visualization methods which have proven to be very useful in analyzing the elementary processes in absorption and charge separation events. Such visualization tools help us to understand the properties of the photochemical and photobiological systems in solar cells.
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Affiliation(s)
- Peng Song
- Department of Physics, Liaoning University, Shenyang, 110036, P. R. China.,Beijing National Laboratory for Condensed Matter Physics, Institute of Physics Chinese Academy of Science, Beijing, 100190, P. R. China.,State Key laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics Chinese Academy of Science, Dalian, 116023, P. R. China
| | - Yuanzuo Li
- Beijing National Laboratory for Condensed Matter Physics, Institute of Physics Chinese Academy of Science, Beijing, 100190, P. R. China.,College of Science, Northeast Forestry University, Harbin, 150040, P. R. China
| | - Fengcai Ma
- Department of Physics, Liaoning University, Shenyang, 110036, P. R. China
| | - Tõnu Pullerits
- Department of Chemical Physics, Lund University, Box 124, Lund, 22100, Sweden.,State Key laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics Chinese Academy of Science, Dalian, 116023, P. R. China
| | - Mengtao Sun
- Department of Physics, Liaoning University, Shenyang, 110036, P. R. China.,Beijing National Laboratory for Condensed Matter Physics, Institute of Physics Chinese Academy of Science, Beijing, 100190, P. R. China
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46
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Spectroscopy and Chemical Bonding in Transition Metal Complexes. STRUCTURE AND BONDING 2016. [DOI: 10.1007/430_2015_195] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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47
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Glebov EM, Pozdnyakov IP, Plyusnin VF, Khmelinskii I. Primary reactions in the photochemistry of hexahalide complexes of platinum group metals: A minireview. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2015. [DOI: 10.1016/j.jphotochemrev.2015.05.003] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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48
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Knoll JD, Albani BA, Turro C. New Ru(II) complexes for dual photoreactivity: ligand exchange and (1)O2 generation. Acc Chem Res 2015; 48:2280-7. [PMID: 26186416 DOI: 10.1021/acs.accounts.5b00227] [Citation(s) in RCA: 132] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Uncovering the factors that govern the electronic structure of Ru(II)-polypyridyl complexes is critical in designing new compounds for desired photochemical reactions, and strategies to tune excited states for ligand dissociation and (1)O2 production are discussed herein. The generally accepted mechanism for photoinduced ligand dissociation proposes that population of the dissociative triplet ligand field ((3)LF) state proceeds through thermal population from the vibrationally cooled triplet metal-to-ligand charge transfer ((3)MLCT) state; however, temperature-dependent emission spectroscopy provides varied activation energies using the emission and ligand exchange quantum yields for [Ru(bpy)2(L)2](2+) (bpy = 2,2'-bipyridine; L = CH3CN or py). This suggests that population of the (3)LF state proceeds from the vibrationally excited (3)MLCT state. Because the quantum yield of ligand dissociation for nitriles is much more efficient than that for py, steric bulk was introduced into the ligand set to distort the pseudo-octahedral geometry and lower the energy of the (3)LF state. The py dissociation quantum yield with 500 nm irradiation in a series of [Ru(tpy)(NN)(py)](2+) complexes (tpy = 2,2':6',2″-terpyridine; NN = bpy, 6,6'-dimethyl-2,2'-bipyridine (Me2bpy), 2,2'-biquinoline (biq)) increases by 2-3 orders of magnitude with the sterically bulky Me2bpy and biq ligands relative to bpy. Ultrafast transient absorption spectroscopy reveals population of the (3)LF state within 3-7 ps when NN is bulky, and density functional theory calculations support stabilized (3)LF states. Dual activity via ligand dissociation and (1)O2 production can be achieved by careful selection of the ligand set to tune the excited-state dynamics. Incorporation of an extended π system in Ru(II) complexes such as [Ru(bpy)(dppn)(CH3CN)2](2+) (dppn = benzo[i]dipyrido[3,2-a:2',3'-c]phenazine) and [Ru(tpy)(Me2dppn)(py)](2+) (Me2dppn = 3,6-dimethylbenzo[i]dipyrido[3,2-a:2',3'-c]phenazine) introduces low-lying, long-lived dppn/Me2dppn (3)ππ* excited states that generate (1)O2. Similar to [Ru(bpy)2(CH3CN)2](2+), photodissociation of CH3CN occurs upon irradiation of [Ru(bpy)(dppn)(CH3CN)2](2+), although with lower efficiency because of the presence of the (3)ππ* state. The steric bulk in [Ru(tpy)(Me2dppn)(py)](2+) is critical in facilitating the photoinduced py dissociation, as the analogous complex [Ru(tpy)(dppn)(py)](2+) produces (1)O2 with near-unit efficiency. The ability to tune the relative energies of the excited states provides a means to design potentially more active drugs for photochemotherapy because the photorelease of drugs can be coupled to the therapeutic action of reactive oxygen species, effecting cell death via two different mechanisms. The lessons learned about tuning of the excited-state properties can be applied to the use of Ru(II)-polypyridyl compounds in a variety of applications, such as solar energy conversion, sensors and switches, and molecular machines.
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Affiliation(s)
- Jessica D. Knoll
- Department
of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Bryan A. Albani
- Department
of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
| | - Claudia Turro
- Department
of Chemistry and
Biochemistry, The Ohio State University, Columbus, Ohio 43210, United States
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49
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On the mechanism of vibrational control of light-induced charge transfer in donor–bridge–acceptor assemblies. Nat Chem 2015; 7:689-95. [DOI: 10.1038/nchem.2327] [Citation(s) in RCA: 93] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2015] [Accepted: 07/15/2015] [Indexed: 11/08/2022]
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50
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Delor M, Sazanovich IV, Towrie M, Weinstein JA. Probing and Exploiting the Interplay between Nuclear and Electronic Motion in Charge Transfer Processes. Acc Chem Res 2015; 48:1131-9. [PMID: 25789559 DOI: 10.1021/ar500420c] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The Born-Oppenheimer approximation refers to the assumption that the nuclear and electronic wave functions describing a molecular system evolve and can be determined independently. It is now well-known that this approximation often breaks down and that nuclear-electronic (vibronic) coupling contributes greatly to the ultrafast photophysics and photochemistry observed in many systems ranging from simple molecules to biological organisms. In order to probe vibronic coupling in a time-dependent manner, one must use spectroscopic tools capable of correlating the motions of electrons and nuclei on an ultrafast time scale. Recent developments in nonlinear multidimensional electronic and vibrational spectroscopies allow monitoring both electronic and structural factors with unprecedented time and spatial resolution. In this Account, we present recent studies from our group that make use of different variants of frequency-domain transient two-dimensional infrared (T-2DIR) spectroscopy, a pulse sequence combining electronic and vibrational excitations in the form of a UV-visible pump, a narrowband (12 cm(-1)) IR pump, and a broadband (400 cm(-1)) IR probe. In the first example, T-2DIR is used to directly compare vibrational dynamics in the ground and relaxed electronic excited states of Re(Cl)(CO)3(4,4'-diethylester-2,2'-bipyridine) and Ru(4,4'-diethylester-2,2'-bipyridine)2(NCS)2, prototypical charge transfer complexes used in photocatalytic CO2 reduction and electron injection in dye-sensitized solar cells. The experiments show that intramolecular vibrational redistribution (IVR) and vibrational energy transfer (VET) are up to an order of magnitude faster in the triplet charge transfer excited state than in the ground state. These results show the influence of electronic arrangement on vibrational coupling patterns, with direct implications for vibronic coupling mechanisms in charge transfer excited states. In the second example, we show unambiguously that electronic and vibrational movement are coupled in a donor-bridge-acceptor complex based on a Pt(II) trans-acetylide design motif. Time-resolved IR (TRIR) spectroscopy reveals that the rate of electron transfer (ET) is highly dependent on the amount of excess energy localized on the bridge following electronic excitation. Using an adaptation of T-2DIR, we are able to selectively perturb bridge-localized vibrational modes during charge separation, resulting in the donor-acceptor charge separation pathway being completely switched off, with all excess energy redirected toward the formation of a long-lived intraligand triplet state. A series of control experiments reveal that this effect is mode specific: it is only when the high-frequency bridging C≡C stretching mode is pumped that radical changes in photoproduct yields are observed. These experiments therefore suggest that one may perturb electronic movement by stimulating structural motion along the reaction coordinate using IR light. These studies add to a growing body of evidence suggesting that controlling the pathways and efficiency of charge transfer may be achieved through synthetic and perturbative approaches aiming to modulate vibronic coupling. Achieving such control would represent a breakthrough for charge transfer-based applications such as solar energy conversion and molecular electronics.
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Affiliation(s)
- Milan Delor
- Department
of Chemistry, University of Sheffield, Sheffield S3 7HF, U.K
| | - Igor V. Sazanovich
- Central
Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, STFC, Chilton, Oxfordshire OX11 0QX, U.K
| | - Michael Towrie
- Central
Laser Facility, Research Complex at Harwell, Rutherford Appleton Laboratory, Harwell Science and Innovation Campus, STFC, Chilton, Oxfordshire OX11 0QX, U.K
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