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Posada Urrutia M, Dyrager C. Tuning the Emission Properties of 2,1,3-Benzothiadiazoles via Regioselective Substitution. Chemistry 2024; 30:e202400644. [PMID: 38619336 DOI: 10.1002/chem.202400644] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 04/13/2024] [Accepted: 04/15/2024] [Indexed: 04/16/2024]
Abstract
The 2,1,3-benzothiadiazole (BTD) unit is a prominent building block commonly used in various research areas such as optoelectronics and bioimaging. Despite its great versatility, the development of strategies to elaborate BTD has been largely neglected, including exploring its reactivity and understanding how regioselective functionalization can be used to tune the fluorescence emission. Previous focus has primarily been on C4- or C4,C7-substitutions. Here, a series of unsymmetrical mono - and disubstituted BTDs was synthesized and characterized for their photophysical properties. The reaction scope includes all six possible substituent patterns on the BTD benzoid ring (C4-, C5-, C4,C5-, C4,C6-, C4,C7- and C5,C6-substitution), which comprise arrangements that previously been synthetically challenging to access. By introducing a methoxy and/or a phenyl group we demonstrate that the emissive behavior of BTD derivatives strongly depends on the position of the substituent (s). We show that regioselective substitution on BTD can engender long-lived fluorescence and circumvent strong fluorescence quenching in polar protic solvents, which is a limitation of many previously described BTD derivatives.
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Affiliation(s)
| | - Christine Dyrager
- Department of Chemistry-BMC, Uppsala University, Box 576, 751 23, Uppsala, Sweden
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2
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Wang PY, Hsu YC, Chen PH, Chen GY, Liao YK, Cheng PY. Solvent-polarity dependence of ultrafast excited-state dynamics of trans-4-nitrostilbene. Phys Chem Chem Phys 2024; 26:788-807. [PMID: 38088777 DOI: 10.1039/d3cp05245a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2023]
Abstract
Ultrafast excited-state dynamics of the simplest nitrostilbenes, namely trans-4-nitrostilbene (t-NSB), was studied in solvents of various polarities with ultrafast broadband time-resolved fluorescence and transient absorption spectroscopies, and by quantum-chemical computations. The results revealed that the initially excited S1(ππ*) state deactivation dynamics is strongly influenced by the solvent polarity. Specifically, the t-NSB S1-state lifetime decreases by three orders of magnitude from ∼60 ps in high-polarity solvents to ∼60 fs in nonpolar solvents. The strong solvent-polarity dependence arises from the differences in dipole moments among the S1 and relevant states, including the major intersystem crossing (ISC) receiver triplet states, and therefore, the solvent polarity can modulate their relative energies and ISC rates. In nonpolar solvents, the sub-100 fs lifetime is due to a combination of efficient ISC and internal conversion. In medium-polarity solvents, the S1-state population decays via a competing ISC relaxation mechanism in a biphasic manner, and the ISC rates are found to obey the inverse energy gap law of the strong coupling case. In high-polarity solvents, the S1 state is stabilized to a much lower energy such that ISC becomes energetically infeasible, and the S1 state decays via barrier crossing along the torsion angle of the central ethylenic bond to the nonfluorescent perpendicular configuration. Regardless of the initial S1-state deactivation pathways in various solvents, the excited-state population is ultimately trapped in the metastable T1-state perpendicular configuration, at which a slower ISC occurs to bring the system to the ground state and bifurcate into either trans or cis form of NSB.
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Affiliation(s)
- Peng-Yun Wang
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, 30043, Republic of China.
| | - Yu-Cheng Hsu
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, 30043, Republic of China.
| | - Pin-Hsun Chen
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, 30043, Republic of China.
| | - Guan-Yu Chen
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, 30043, Republic of China.
| | - Yi-Kai Liao
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, 30043, Republic of China.
| | - Po-Yuan Cheng
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan, 30043, Republic of China.
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3
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Guzmán-Méndez Ó, Reza MM, Meza B, Jara-Cortés J, Peón J. Solvent Effects on the Singlet-Triplet Couplings in Nitroaromatic Compounds. J Phys Chem B 2023. [PMID: 37327487 DOI: 10.1021/acs.jpcb.3c01143] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/18/2023]
Abstract
Nitrated polycyclic molecules can present the largest singlet-triplet crossing rates among organic molecules. This implies that most of these compounds have no detectable steady-state fluorescence. In addition, some nitroaromatics undergo a complex series of photoinduced atom rearrangements that result in nitric oxide dissociation. The overall photochemistry of these systems depends critically on the competition between the rapid intersystem crossing channel and other excited-state pathways. In this contribution, we sought to characterize the degree of stabilization of the S1 state due to solute-solvent interactions, and to quantify the effect of such stabilization on their photophysical pathways. We studied 2- and 4-nitropyrene (2-NP and 4-NP), which are atypically emissive nitroaromatics in a series of solvents. From steady-state and time-resolved measurements, the S1 state of these molecules shows significant stabilization as the solvent polarity is increased. On the other hand, specific triplet states that are iso-energetic with the emissive singlet (T3 for 2-NP and T2 for 4-NP) in nonpolar solvents become slightly de-stabilized upon increasing the solvent polarity. These combined effects result in rapid singlet-triplet population transfer in nonpolar solvents for both molecules. In contrast, for solvents with even slightly higher polarities, the first excited singlet is stabilized in relation to the specific triplet states, leading to much longer S1 lifetimes. These effects can be summarized as a highly solvent-dependent coupling/decoupling of the manifolds. Similar effects are also likely to be present in other nitroaromatics where there is a dynamic competition between nitric oxide dissociation and intersystem crossing. The drastic effects of the solvent polarity in the manifold crossing pathway should be taken into consideration in both theoretical and experimental studies of nitroaromatics.
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Affiliation(s)
- Óscar Guzmán-Méndez
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510 Ciudad de México, México
| | - Mariana M Reza
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510 Ciudad de México, México
| | - Brandon Meza
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510 Ciudad de México, México
| | - Jesús Jara-Cortés
- Unidad Académica de Ciencias Básicas e Ingenierías, Universidad Autónoma de Nayarit, Tepic 63155, México
| | - Jorge Peón
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510 Ciudad de México, México
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4
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Wu Y, Wang Y, Guan H, Du Y, Zheng X, Xue J. Effect of electron-donating substitution on the triplet state reactivities of 1-nitronaphthalene. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2023; 286:121997. [PMID: 36308824 DOI: 10.1016/j.saa.2022.121997] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 09/23/2022] [Accepted: 10/13/2022] [Indexed: 06/16/2023]
Abstract
Nitro-polycyclic aromatic hydrocarbons (nitro-PAHs), often found in polluted air, are carcinogenic and mutagenic. The nitro group increases the spin-orbit coupling and results in the lowest excited triplet (T1) on the picosecond time scale with a high yield. The electron-donating substituents have a significant influence on the photophysics and photochemistry of nitro-PAHs. We used transient absorption spectroscopy and kinetic analysis to investigate the reactivities of the T1 state 1-methoxy-4-nitronaphthalene (3MeO-NN) and 1-methyl-4-nitronaphthalene (3Me-NN). The results show that the methoxy and methyl substitutions have a minor effect on their hydrogen abstraction and electron accepting abilities. The main distinction is their reaction rates towards protons. The second order rate constant of 3MeO-NN towards protons is three orders of magnitude greater than that of 3Me-NN, indicating that 3MeO-NN has a stronger hydrogen bond accepting ability. The kinetic analysis reveals that the dimer of 2,2,2-trifluoroethanol participates in the reaction with 3MeO-NN. These results suggest that the formation of the hydrogen-bonded complex is responsible for the unusually short lifetime of 3MeO-NN in methanol solution and the lack of hydrogen abstraction radicals during the decay of 3MeO-NN in methanol.
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Affiliation(s)
- Yu Wu
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Yangxin Wang
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Huaiyu Guan
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Yong Du
- Centre for THz Research, Jiliang University, Hangzhou 310018, China
| | - Xuming Zheng
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jiadan Xue
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China; Key Laboratory of Surface & Interface Science of Polymer Materials of Zhejiang Province, Zhejiang Sci-Tech University, Hangzhou 310018, China.
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5
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Pérez‐Márquez LA, Perretti MD, García‐Rodríguez R, Lahoz F, Carrillo R. A Fluorescent Cage for Supramolecular Sensing of 3‐Nitrotyrosine in Human Blood Serum. Angew Chem Int Ed Engl 2022; 61:e202205403. [PMID: 35511212 PMCID: PMC9401051 DOI: 10.1002/anie.202205403] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Indexed: 12/26/2022]
Abstract
3‐Nitrotyrosine (NT) is generated by the action of peroxynitrite and other reactive nitrogen species (RNS), and as a consequence it is accumulated in inflammation‐associated conditions. This is particularly relevant in kidney disease, where NT concentration in blood is considerably high. Therefore, NT is a crucial biomarker of renal damage, although it has been underestimated in clinical diagnosis due to the lack of an appropriate sensing method. Herein we report the first fluorescent supramolecular sensor for such a relevant compound: Fluorescence by rotational restriction of tetraphenylethenes (TPE) in a covalent cage is selectively quenched in human blood serum by 3‐nitrotyrosine (NT) that binds to the cage with high affinity, allowing a limit of detection within the reported physiological concentrations of NT in chronic kidney disease.
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Affiliation(s)
- Lidia A. Pérez‐Márquez
- Instituto de Productos Naturales y Agrobiología (IPNA-CSIC) Avda. Astrofísico Fco. Sánchez 3 38206 La Laguna Spain
| | - Marcelle D. Perretti
- Instituto de Productos Naturales y Agrobiología (IPNA-CSIC) Avda. Astrofísico Fco. Sánchez 3 38206 La Laguna Spain
| | - Raúl García‐Rodríguez
- GIR MIOMeT-IU Cinquima-Química Inorgánica Facultad de Ciencias Campus Miguel Delibes Universidad de Valladolid 47011 Valladolid Spain
| | - Fernando Lahoz
- Departamento de Física, IUdEA Universidad de La Laguna 38200 San Cristóbal de La Laguna Tenerife Spain
| | - Romen Carrillo
- Instituto de Productos Naturales y Agrobiología (IPNA-CSIC) Avda. Astrofísico Fco. Sánchez 3 38206 La Laguna Spain
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6
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Pérez-Márquez LA, Perretti MD, García-Rodríguez R, Lahoz F, Carrillo R. A Fluorescent Cage for Supramolecular Sensing of 3‐Nitrotyrosine in Human Blood Serum. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202205403] [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]
Affiliation(s)
- Lidia Ana Pérez-Márquez
- Instituto de Productos Naturales y Agrobiología: Instituto de Productos Naturales y Agrobiologia Molecular Sciences SPAIN
| | - Marcelle Dayana Perretti
- Instituto de Productos Naturales y Agrobiología: Instituto de Productos Naturales y Agrobiologia Molecular Sciences SPAIN
| | | | - Fernando Lahoz
- Universidad de La Laguna Facultad de Física: Universidad de La Laguna Facultad de Fisica Departamento de Física SPAIN
| | - Romen Carrillo
- Instituto de Productos Naturales y Agrobiología: Instituto de Productos Naturales y Agrobiologia Ciencias Moleculares Avda. Astrofísico Francisco Sánchez 3 38206 La Laguna SPAIN
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7
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Rodríguez-Córdoba W, Gutiérrez-Arzaluz L, Cortés-Guzmán F, Peon J. Excited state dynamics and photochemistry of nitroaromatic compounds. Chem Commun (Camb) 2021; 57:12218-12235. [PMID: 34735557 DOI: 10.1039/d1cc04999b] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Nitrated aromatic molecules have unique photoinduced channels. Due to the presence of oxygen-centered non-bonding orbitals, they can undergo sub-picosecond intersystem crossing showing one of the strongest couplings between the singlet and triplet manifolds among organic molecules. Several nitroaromatic compounds also have a distinctive nitric oxide photodissociation channel which occurs through a complex sequence of atom rearrangements and state changes. These remarkable processes have stimulated the attention of several research groups over the last few years who have applied modern femtosecond spectroscopies and new computational methods to these topics. Nitroaromatic molecules also have demonstrated their value as case-studies, where they can serve to understand the influence of torsional motions between the nitro substituent and the aromatic system in the conversions between states. In this contribution we highlight several of the recent results in this area. Due to the importance of the atmospheric photochemistry of nitrated compounds and their accumulating applications as nitric oxide release agents, continued research about the effects of the different state orderings, substitution patterns, and solvent effects is central to the development of future applications and for a better understanding of their environmental pathways. From this analysis, several pending issues are highlighted, which include the nature of the dominant singlet state involved in intersystem crossing, the role of the formation of charge-transfer states, the yield of the internal conversion channel to the electronic ground state, and a more generalized understanding of the sequence of steps which lead to nitric oxide dissociation.
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Affiliation(s)
- William Rodríguez-Córdoba
- Facultad de ciencias, Escuela de Física, Laboratorio de Fotónica y Optoelectrónica, Universidad Nacional de Colombia - Sede Medellín, Calle 59 A No. 63-20, A.A. 3840, Medellín, Colombia.
| | - Luis Gutiérrez-Arzaluz
- Division of Physical Sciences and Engineering (PSE), King Abdullah University of Science and Technology (KAUST), Thuwal 23955-6900, Saudi Arabia.
| | - Fernando Cortés-Guzmán
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510 D.F., Mexico.
| | - Jorge Peon
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510 D.F., Mexico.
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8
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Sadowski B, Kaliszewska M, Poronik YM, Czichy M, Janasik P, Banasiewicz M, Mierzwa D, Gadomski W, Lohrey TD, Clark JA, Łapkowski M, Kozankiewicz B, Vullev VI, Sobolewski AL, Piatkowski P, Gryko DT. Potent strategy towards strongly emissive nitroaromatics through a weakly electron-deficient core. Chem Sci 2021; 12:14039-14049. [PMID: 34760187 PMCID: PMC8565362 DOI: 10.1039/d1sc03670j] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 09/05/2021] [Indexed: 01/16/2023] Open
Abstract
Nitroaromatics seldom fluoresce. The importance of electron-deficient (n-type) conjugates, however, has inspired a number of strategies for suppressing the emission-quenching effects of the strongly electron-withdrawing nitro group. Here, we demonstrate how such strategies yield fluorescent nitroaryl derivatives of dipyrrolonaphthyridinedione (DPND). Nitro groups near the DPND core quench its fluorescence. Conversely, nitro groups placed farther from the core allow some of the highest fluorescence quantum yields ever recorded for nitroaromatics. This strategy of preventing the known processes that compete with photoemission, however, leads to the emergence of unprecedented alternative mechanisms for fluorescence quenching, involving transitions to dark nπ* singlet states and aborted photochemistry. Forming nπ* triplet states from ππ* singlets is a classical pathway for fluorescence quenching. In nitro-DPNDs, however, these ππ* and nπ* excited states are both singlets, and they are common for nitroaryl conjugates. Understanding the excited-state dynamics of such nitroaromatics is crucial for designing strongly fluorescent electron-deficient conjugates.
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Affiliation(s)
- Bartłomiej Sadowski
- Institute of Organic Chemistry, Polish Academy of Sciences Kasprzaka 44/52 01-224 Warsaw Poland
| | - Marzena Kaliszewska
- Faculty of Chemistry, University of Warsaw Zwirki i Wigury 101 02-089 Warsaw Poland
| | - Yevgen M Poronik
- Institute of Organic Chemistry, Polish Academy of Sciences Kasprzaka 44/52 01-224 Warsaw Poland
| | - Małgorzata Czichy
- Faculty of Chemistry, Silesian University of Technology Strzody 9 44-100 Gliwice Poland
| | - Patryk Janasik
- Faculty of Chemistry, Silesian University of Technology Strzody 9 44-100 Gliwice Poland
| | - Marzena Banasiewicz
- Institute of Physics, Polish Academy of Sciences Aleja Lotnikow 32/46 02-668 Warsaw Poland
| | - Dominik Mierzwa
- Institute of Organic Chemistry, Polish Academy of Sciences Kasprzaka 44/52 01-224 Warsaw Poland
| | - Wojciech Gadomski
- Faculty of Chemistry, University of Warsaw Zwirki i Wigury 101 02-089 Warsaw Poland
| | - Trevor D Lohrey
- Department of Chemistry, University of California Berkeley, 420 Latimer Hall Berkeley CA USA
- Chemical Sciences Division, Lawrence Berkeley National Laboratory 1 Cyclotron Road Berkeley CA USA
| | - John A Clark
- Department of Bioengineering, University of California Riverside, 900 University Ave. Riverside CA 92521 USA
| | - Mieczysław Łapkowski
- Faculty of Chemistry, Silesian University of Technology Strzody 9 44-100 Gliwice Poland
| | - Bolesław Kozankiewicz
- Institute of Physics, Polish Academy of Sciences Aleja Lotnikow 32/46 02-668 Warsaw Poland
| | - Valentine I Vullev
- Department of Bioengineering, University of California Riverside, 900 University Ave. Riverside CA 92521 USA
- Department of Chemistry, University of California Riverside, 900 University Ave. Riverside CA 92521 USA
- Department of Biochemistry, University of California Riverside, 900 University Ave. Riverside CA 92521 USA
- Materials Science and Engineering Program, University of California Riverside, 900 University Ave. Riverside CA 92521 USA
| | - Andrzej L Sobolewski
- Institute of Physics, Polish Academy of Sciences Aleja Lotnikow 32/46 02-668 Warsaw Poland
| | - Piotr Piatkowski
- Faculty of Chemistry, University of Warsaw Zwirki i Wigury 101 02-089 Warsaw Poland
| | - Daniel T Gryko
- Institute of Organic Chemistry, Polish Academy of Sciences Kasprzaka 44/52 01-224 Warsaw Poland
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10
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Poronik YM, Baryshnikov GV, Deperasińska I, Espinoza EM, Clark JA, Ågren H, Gryko DT, Vullev VI. Deciphering the unusual fluorescence in weakly coupled bis-nitro-pyrrolo[3,2-b]pyrroles. Commun Chem 2020; 3:190. [PMID: 36703353 PMCID: PMC9814504 DOI: 10.1038/s42004-020-00434-6] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2020] [Accepted: 11/13/2020] [Indexed: 01/29/2023] Open
Abstract
Electron-deficient π-conjugated functional dyes lie at the heart of organic optoelectronics. Adding nitro groups to aromatic compounds usually quenches their fluorescence via inter-system crossing (ISC) or internal conversion (IC). While strong electronic coupling of the nitro groups with the dyes ensures the benefits from these electron-withdrawing substituents, it also leads to fluorescence quenching. Here, we demonstrate how such electronic coupling affects the photophysics of acceptor-donor-acceptor fluorescent dyes, with nitrophenyl acceptors and a pyrrolo[3,2-b]pyrrole donor. The position of the nitro groups and the donor-acceptor distance strongly affect the fluorescence properties of the bis-nitrotetraphenylpyrrolopyrroles. Concurrently, increasing solvent polarity quenches the emission that recovers upon solidifying the media. Intramolecular charge transfer (CT) and molecular dynamics, therefore, govern the fluorescence of these nitro-aromatics. While balanced donor-acceptor coupling ensures fast radiative deactivation and slow ISC essential for large fluorescence quantum yields, vibronic borrowing accounts for medium dependent IC via back CT. These mechanistic paradigms set important design principles for molecular photonics and electronics.
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Affiliation(s)
- Yevgen M. Poronik
- grid.413454.30000 0001 1958 0162Institute of Organic Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Glib V. Baryshnikov
- grid.8993.b0000 0004 1936 9457Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden
| | - Irena Deperasińska
- grid.413454.30000 0001 1958 0162Institute of Physics, Polish Academy of Sciences, Warsaw, Poland
| | - Eli M. Espinoza
- grid.266097.c0000 0001 2222 1582Department of Chemistry, University of California, Riverside, CA USA ,grid.47840.3f0000 0001 2181 7878Present Address: College of Bioengineering, University of California, Berkeley, CA 94720 USA
| | - John A. Clark
- grid.266097.c0000 0001 2222 1582Department of Bioengineering, University of California, Riverside, CA USA
| | - Hans Ågren
- grid.8993.b0000 0004 1936 9457Department of Physics and Astronomy, Uppsala University, Uppsala, Sweden ,grid.77602.340000 0001 1088 3909Department of Physics, Tomsk State University, 36 Lenin Avenue, Tomsk, 634050 Russian Federation
| | - Daniel T. Gryko
- grid.413454.30000 0001 1958 0162Institute of Organic Chemistry, Polish Academy of Sciences, Warsaw, Poland
| | - Valentine I. Vullev
- grid.266097.c0000 0001 2222 1582Department of Chemistry, University of California, Riverside, CA USA ,grid.266097.c0000 0001 2222 1582Department of Bioengineering, University of California, Riverside, CA USA ,grid.266097.c0000 0001 2222 1582Department of Biochemistry, University of California, Riverside, CA USA ,grid.266097.c0000 0001 2222 1582Materials Science and Engineering Program, University of California, Riverside, CA USA
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11
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Wilson J, Octaviani M, Bandowe BAM, Wietzoreck M, Zetzsch C, Pöschl U, Berkemeier T, Lammel G. Modeling the Formation, Degradation, and Spatiotemporal Distribution of 2-Nitrofluoranthene and 2-Nitropyrene in the Global Atmosphere. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2020; 54:14224-14234. [PMID: 33112146 PMCID: PMC7676291 DOI: 10.1021/acs.est.0c04319] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Revised: 10/07/2020] [Accepted: 10/16/2020] [Indexed: 05/19/2023]
Abstract
Polycyclic aromatic hydrocarbons (PAHs) are common atmospheric pollutants and known to cause adverse health effects. Nitrated PAHs (NPAHs) are formed in combustion activities and by nitration of PAHs in the atmosphere and may be equally or more toxic, but their spatial and temporal distribution in the atmosphere is not well characterized. Using the global EMAC model with atmospheric chemistry and surface compartments coupled, we investigate the formation, abundance, and fate of two secondarily formed NPAHs, 2-nitrofluoranthene (2-NFLT) and 2-nitropyrene (2-NPYR). The default reactivity scenario, the model with the simplest interpretation of parameters from the literature, tends to overestimate both absolute concentrations and NPAH/PAH ratios at observational sites. Sensitivity scenarios indicate that NO2-dependent NPAH formation leads to better agreement between measured and predicted NPAH concentrations and that photodegradation is the most important loss process of 2-NFLT and 2-NPYR. The highest concentrations of 2-NFLT and 2-NPYR are found in regions with strong PAH emissions, but because of continued secondary formation from the PAH precursors, these two NPAHs are predicted to be spread across the globe.
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Affiliation(s)
- Jake Wilson
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, 55128 Mainz, Germany
| | - Mega Octaviani
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, 55128 Mainz, Germany
| | | | - Marco Wietzoreck
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, 55128 Mainz, Germany
| | - Cornelius Zetzsch
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, 55128 Mainz, Germany
- Bayreuth
Centre for Ecology and Environmental Research, University of Bayreuth, 95448 Bayreuth, Germany
| | - Ulrich Pöschl
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, 55128 Mainz, Germany
| | - Thomas Berkemeier
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, 55128 Mainz, Germany
| | - Gerhard Lammel
- Multiphase
Chemistry Department, Max Planck Institute
for Chemistry, 55128 Mainz, Germany
- Research
Centre for Toxic Compounds in the Environment, Masaryk University, Kamenice 5, 62500 Brno, Czech Republic
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12
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Long J, Ye Z, Du Y, Zheng XM, Xue JD. Direct observation of transient species generated from protonation and deprotonation of the lowest triplet of p-nitrophenylphenol. CHINESE J CHEM PHYS 2020. [DOI: 10.1063/1674-0068/cjcp2006107] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
- Jing Long
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Zhao Ye
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Yong Du
- Centre for THz Research, China Jiliang University, Hangzhou 310018, China
| | - Xu-ming Zheng
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
| | - Jia-dan Xue
- Department of Chemistry, Zhejiang Sci-Tech University, Hangzhou 310018, China
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13
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Zobel JP, González L. Nonadiabatic Dynamics Simulation Predict Intersystem Crossing in Nitroaromatic Molecules on a Picosecond Time Scale. CHEMPHOTOCHEM 2019; 3:833-845. [PMID: 31681833 PMCID: PMC6813632 DOI: 10.1002/cptc.201900108] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2019] [Revised: 05/06/2019] [Indexed: 12/19/2022]
Abstract
Previous time-resolved spectroscopic experiments and static quantum-chemical calculations attributed nitronaphthalene derivatives one of the fastest time scales for intersystem crossing within organic molecules, reaching the 100 fs mark. Nonadiabatic dynamics simulations on three nitronaphthalene derivatives challenge this view, showing that the experimentally observed ∼100 fs process corresponds to internal conversion in the singlet manifolds. Intersystem crossing, instead, takes place on a longer time scale of ∼1 ps. The dynamics simulations further reveal that the spin transitions occur via two distinct pathways with different contribution for the three systems, which are determined by electronic factors and the torsion of the nitro group. This study, therefore, indicates that the existence of sub-picosecond intersystem crossing in other nitroaromatic molecules should be questioned.
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Affiliation(s)
- J. Patrick Zobel
- Division of Theoretical Chemistry, KemicentrumLund UniversityP.O. Box 124SE-221 00LundSweden
| | - Leticia González
- Institute of Theoretical ChemistryUniversity of ViennaWähringer Straße 17A-1090ViennaAustria
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14
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Zobel JP, Nogueira JJ, González L. Mechanism of Ultrafast Intersystem Crossing in 2-Nitronaphthalene. Chemistry 2018; 24:5379-5387. [PMID: 29377370 PMCID: PMC5947663 DOI: 10.1002/chem.201705854] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2017] [Indexed: 01/10/2023]
Abstract
Nitronaphthalene derivatives efficiently populate their electronically excited triplet states upon photoexcitation through ultrafast intersystem crossing (ISC). Despite having been studied extensively by time-resolved spectroscopy, the reasons behind their ultrafast ISC remain unknown. Herein, we present the first ab initio nonadiabatic molecular dynamics study of a nitronaphthalene derivative, 2-nitronaphthalene, including singlet and triplet states. We find that there are two distinct ISC reaction pathways involving different electronic states at distinct nuclear configurations. The high ISC efficiency is explained by the very small electronic and nuclear alterations that the chromophore needs to undergo during the singlet-triplet transition in the dominating ISC pathway after initial dynamics in the singlet manifold. The insights gained in this work are expected to shed new light on the photochemistry of other nitro polycyclic aromatic hydrocarbons that exhibit ultrafast intersystem crossing.
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Affiliation(s)
- J. Patrick Zobel
- Institute of Theoretical Chemistry, Faculty of ChemistryUniversity of ViennaWähringer Straße 171090ViennaAustria
| | - Juan J. Nogueira
- Institute of Theoretical Chemistry, Faculty of ChemistryUniversity of ViennaWähringer Straße 171090ViennaAustria
| | - Leticia González
- Institute of Theoretical Chemistry, Faculty of ChemistryUniversity of ViennaWähringer Straße 171090ViennaAustria
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15
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Matsumoto H, Azuma K, Nishimura Y, Arai T. A Drastic Red-shift of Tautomer Fluorescence Depending on the Substitution Pattern of Pyrene–Urea Compounds Generated by Excited State Intermolecular Proton Transfer. CHEM LETT 2018. [DOI: 10.1246/cl.171187] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Hisato Matsumoto
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Kyoko Azuma
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Yoshinobu Nishimura
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
| | - Tatsuo Arai
- Graduate School of Pure and Applied Sciences, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, Ibaraki 305-8571, Japan
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16
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Larsen MAB, Stephansen AB, Alarousu E, Pittelkow M, Mohammed OF, Sølling TI. Solvent-dependent dual fluorescence of the push-pull system 2-diethylamino-7-nitrofluorene. Phys Chem Chem Phys 2018; 20:5942-5951. [PMID: 29423491 DOI: 10.1039/c8cp00235e] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The solvent-dependent excited state behavior of the molecular push-pull system 2-diethylamino-7-nitrofluorene has been explored using femtosecond transient absorption spectroscopy in combination with density functional theory calculations. Several excited state minima have been identified computationally, all possessing significant intramolecular charge transfer character. The experimentally observed dual fluorescence is suggested to arise from a planar excited state minimum and another minimum reached by twisting of the aryl-nitrogen bond of the amino group. The majority of the excited state population, however, undergo non-radiative transitions and potential excited state deactivation pathways are assessed in the computational investigation. A third excited state conformer, characterized by twisting around the aryl-nitrogen bond of the nitro group, is reasoned to be responsible for the majority of the non-radiative decays and a crossing between the excited state and ground state is localized. Additionally, ultrafast intersystem crossing is observed in the apolar solvent cyclohexane and rationalized to occur via an El-Sayed assisted transition from one of the identified excited state minima. The solvent thus determines more than just the fluorescence lifetime and shapes the potential energy landscape, thereby dictating the available excited state pathways.
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Affiliation(s)
- M A B Larsen
- Department of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark.
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17
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Xu C, Gu FL, Zhu C. Ultrafast intersystem crossing for nitrophenols: ab initio nonadiabatic molecular dynamics simulation. Phys Chem Chem Phys 2018; 20:5606-5616. [DOI: 10.1039/c7cp08601f] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Ultrafast intersystem crossing mechanisms for two p- and m-nitrophenol groups (PNP and MNP) have been investigated using ab initio nonadiabatic molecular dynamics simulations at the 6SA-CASSCF level of theory.
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Affiliation(s)
- Chao Xu
- Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education; School of Chemistry & Environment of South China Normal University
- Guangzhou 51006
- P. R. China
| | - Feng Long Gu
- Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education; School of Chemistry & Environment of South China Normal University
- Guangzhou 51006
- P. R. China
| | - Chaoyuan Zhu
- Key Laboratory of Theoretical Chemistry of Environment, Ministry of Education; School of Chemistry & Environment of South China Normal University
- Guangzhou 51006
- P. R. China
- Department of Applied Chemistry, Institute of Molecular Science and Center for Interdisciplinary Molecular Science, National Chiao-Tung University
- Hsinchu 30010
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18
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Brister MM, Piñero-Santiago LE, Morel M, Arce R, Crespo-Hernández CE. Photochemical Relaxation Pathways in Dinitropyrene Isomer Pollutants. J Phys Chem A 2017; 121:8197-8206. [PMID: 28984454 DOI: 10.1021/acs.jpca.7b04769] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
Dinitropyrenes are polycyclic aromatic pollutants prevalent in the environment. While their transformations by sunlight in the environment have been documented, the effect that the nitro-group substitution pattern has on the relaxation pathways has not been extensively studied. In this contribution, the steady-state and femtosecond-to-microsecond excited-state dynamics of 1,3-dinitropyrene and 1,8-dinitropyrene isomers are investigated upon visible light excitation at 425 nm and compared with those recently reported for the 1,6-dinitropyrene isomer. The experimental results are complemented with ground- and excited-state density functional calculations. It is shown that excitation at 425 nm results in the ultrafast branching of the excited-state population in the S1 state to populate the triplet state in ca. 90% yield and to form a nitropyrenoxy radical in less than 10% yield. In addition, the position of the NO2 group does not affect significantly the excited-state relaxation mechanism, while it does influence the absorption and fluorescence spectra, the fluorescence, triplet, singlet oxygen, and photodegradation yields, as well as the relative yield of radical formation. Radical formation is implicated in the photodegradation of these pollutants, while in the presence of hydrogen donors, direct reactions from the triplet state are also observed.
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Affiliation(s)
- Matthew M Brister
- Department of Chemistry, Case Western Reserve University , 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Luis E Piñero-Santiago
- Department of Chemistry, University of Puerto Rico , Río Piedras Campus, San Juan, Puerto Rico 00931, United States
| | - María Morel
- Department of Chemistry, University of Puerto Rico , Río Piedras Campus, San Juan, Puerto Rico 00931, United States
| | - Rafael Arce
- Department of Chemistry, University of Puerto Rico , Río Piedras Campus, San Juan, Puerto Rico 00931, United States
| | - Carlos E Crespo-Hernández
- Department of Chemistry, Case Western Reserve University , 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
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19
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Gutiérrez-Arzaluz L, López-Arteaga R, Cortés-Guzmán F, Peon J. Nitrated Fluorophore Formation upon Two-Photon Excitation of an Azide with Extended Conjugation. J Phys Chem B 2017; 121:9910-9919. [PMID: 28981286 DOI: 10.1021/acs.jpcb.7b09446] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
The transformation of an aromatic azide into a highly fluorescent species through a nonlinear optical process was studied. The azide system was designed to undergo N2 release and nitrene to nitro conversion upon two-photon electronic excitation. The formation of the nitro form of the compound through reactions with O2 and its high radiative quantum yield implies that the azide can be used as a biphotonic activatable fluorogen. The electronic state in which the azide to nitrene transformation takes place can be accessed nonlinearly with near-infrared light which allows for photoactivation with commonly available lasers. Furthermore, the system was built with a sulfonate functionality which allows for the molecule to be adsorbed at surfaces like that of cadmium sulfide nanocrystals which further improves the nonlinear optical absorption properties in the composite, through an energy transfer mechanism. The yield of the process as a function of the excitation photon energy together with computational studies indicate that the N2 release in this azide is due to a reactive channel in the second singlet excited state of the molecule. This feature implies that the system is intrinsically photostable for excitation below and above a certain wavelength and that the system can be phototriggered selectively by the nonlinear optical process.
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Affiliation(s)
- Luis Gutiérrez-Arzaluz
- Instituto de Química, Universidad Nacional Autónoma de México , Circuito Exterior, Ciudad Universitaria, México, 04510, México
| | - Rafael López-Arteaga
- Instituto de Química, Universidad Nacional Autónoma de México , Circuito Exterior, Ciudad Universitaria, México, 04510, México
| | - Fernando Cortés-Guzmán
- Instituto de Química, Universidad Nacional Autónoma de México , Circuito Exterior, Ciudad Universitaria, México, 04510, México
| | - Jorge Peon
- Instituto de Química, Universidad Nacional Autónoma de México , Circuito Exterior, Ciudad Universitaria, México, 04510, México
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20
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Merz J, Fink J, Friedrich A, Krummenacher I, Al Mamari HH, Lorenzen S, Haehnel M, Eichhorn A, Moos M, Holzapfel M, Braunschweig H, Lambert C, Steffen A, Ji L, Marder TB. Pyrene Molecular Orbital Shuffle-Controlling Excited State and Redox Properties by Changing the Nature of the Frontier Orbitals. Chemistry 2017; 23:13164-13180. [PMID: 28718975 DOI: 10.1002/chem.201702594] [Citation(s) in RCA: 82] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2017] [Indexed: 01/01/2023]
Abstract
We show that by judicious choice of substituents at the 2- and 7-positions of pyrene, the frontier orbital order of pyrene can be modified, giving enhanced control over the nature and properties of the photoexcited states and the redox potentials. Specifically, we introduced a julolidine-like moiety and Bmes2 (mes=2,4,6-Me3 C6 H2 ) as very strong donor (D) and acceptor (A), respectively, giving 2,7-D-π-D- and unsymmetric 2,7-D-π-A-pyrene derivatives, in which the donor destabilizes the HOMO-1 and the acceptor stabilizes the LUMO+1 of the pyrene core. Consequently, for 2,7-substituted pyrene derivatives, unusual properties are obtained. For example, very large bathochromic shifts were observed for all of our compounds, and unprecedented green light emission occurs for the D/D system. In addition, very high radiative rate constants in solution and in the solid state were recorded for the D-π-D- and D-π-A-substituted compounds. All compounds show reversible one-electron oxidations, and Jul2 Pyr exhibits a second oxidation, with the largest potential splitting (ΔE=440 mV) thus far reported for 2,7-substituted pyrenes. Spectroelectrochemical measurements confirm an unexpectedly strong coupling between the 2,7-substituents in our pyrene derivatives.
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Affiliation(s)
- Julia Merz
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Julian Fink
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Alexandra Friedrich
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Ivo Krummenacher
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Hamad H Al Mamari
- Department of Chemistry, College of Science, Sultan Qaboos University, PO Box 36, Al Khoud, 123, Muscat, Sultanate of Oman
| | - Sabine Lorenzen
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Martin Haehnel
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Antonius Eichhorn
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Michael Moos
- Institut für Organische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Marco Holzapfel
- Institut für Organische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Holger Braunschweig
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Christoph Lambert
- Institut für Organische Chemie, Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Andreas Steffen
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Lei Ji
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
| | - Todd B Marder
- Institut für Anorganische Chemie and Institute for Sustainable Chemistry, & Catalysis with Boron (ICB), Julius-Maximilians-Universität Würzburg, Am Hubland, 97074, Würzburg, Germany
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21
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Stephansen AB, Sølling TI. Distortion dependent intersystem crossing: A femtosecond time-resolved photoelectron spectroscopy study of benzene, toluene, and p-xylene. STRUCTURAL DYNAMICS (MELVILLE, N.Y.) 2017; 4:044008. [PMID: 28345010 PMCID: PMC5336472 DOI: 10.1063/1.4977735] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Accepted: 02/16/2017] [Indexed: 05/05/2023]
Abstract
The competition between ultrafast intersystem crossing and internal conversion in benzene, toluene, and p-xylene is investigated with time-resolved photoelectron spectroscopy and quantum chemical calculations. By exciting to S2 out-of-plane symmetry breaking, distortions are activated at early times whereupon spin-forbidden intersystem crossing becomes (partly) allowed. Natural bond orbital analysis suggests that the pinnacle carbon atoms distorting from the aromatic plane change hybridization between the planar Franck-Condon geometry and the deformed (boat-shaped) S2 equilibrium geometry. The effect is observed to increase in the presence of methyl-groups on the pinnacle carbon-atoms, where largest extents of σ and π orbital-mixing are observed. This is fully consistent with the time-resolved spectroscopy data: Toluene and p-xylene show evidence for ultrafast triplet formation competing with internal conversion, while benzene appears to only decay via internal conversion within the singlet manifold. For toluene and p-xylene, internal conversion to S1 and intersystem crossing to T3 occur within the time-resolution of our instrument. The receiver triplet state (T3) is found to undergo internal conversion in the triplet manifold within ≈100-150 fs (toluene) or ≈180-200 fs (p-xylene) as demonstrated by matching rise and decay components of upper and lower triplet states. Overall, the effect of methylation is found to both increase the intersystem crossing probability and direct the molecular axis of the excited state dynamics.
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Affiliation(s)
- Anne B Stephansen
- Department of Chemistry, University of Copenhagen , Universitetsparken 5, DK-2100 København Ø, Denmark
| | - Theis I Sølling
- Department of Chemistry, University of Copenhagen , Universitetsparken 5, DK-2100 København Ø, Denmark
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22
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García-Berríos ZI, Arce R, Burgos-Martínez M, Burgos-Polanco ND. Phototransformations of environmental contaminants in models of the aerosol: 2 and 4-Nitropyrene. J Photochem Photobiol A Chem 2017. [DOI: 10.1016/j.jphotochem.2016.08.018] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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23
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Rajagopal SK, Mallia AR, Hariharan M. Enhanced intersystem crossing in carbonylpyrenes. Phys Chem Chem Phys 2017; 19:28225-28231. [DOI: 10.1039/c7cp04834c] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Photoexcited state relaxation of carbonylpyrenes displays ultrafast intersystem crossing to generate near-unity triplet formation.
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Affiliation(s)
- Shinaj K. Rajagopal
- School of Chemistry
- Indian Institute of Science Education and Research Thiruvananthapuram
- Thiruvananthapuram 695551
- India
| | - Ajith R. Mallia
- School of Chemistry
- Indian Institute of Science Education and Research Thiruvananthapuram
- Thiruvananthapuram 695551
- India
| | - Mahesh Hariharan
- School of Chemistry
- Indian Institute of Science Education and Research Thiruvananthapuram
- Thiruvananthapuram 695551
- India
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Brister MM, Piñero-Santiago LE, Morel M, Arce R, Crespo-Hernández CE. The Photochemical Branching Ratio in 1,6-Dinitropyrene Depends on the Excitation Energy. J Phys Chem Lett 2016; 7:5086-5092. [PMID: 27973879 DOI: 10.1021/acs.jpclett.6b02549] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
Nitropolycyclic aromatic hydrocarbons constitute one of the most disconcerting classes of pollutants. Photochemical degradation is thought to be a primary mode of their natural removal from the environment, but the microscopic mechanism leading to product formation as a function of excitation wavelength is poorly understood. In this Letter, it is revealed that excitation of 1,6-dinitropyrene with 425, 415, or 340 nm radiation leads to an increasing amount of radical production through photodissociation at the expense of triplet-state population-the two primary reaction pathways in this class of pollutants. Radical formation requires overcoming an energy barrier in the excited singlet manifold. This activation energy explains the large fraction of the initial singlet-state population that intersystem crosses to a doorway triplet state, instead of leading overwhelmingly to photodissociation. The unforeseen excitation wavelength dependence of this branching process is expected to regulate the photochemistry of 1,6-dinitropyrene and possibly of other nitroaromatic pollutants in the environment.
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Affiliation(s)
- Matthew M Brister
- Department of Chemistry, Case Western Reserve University , 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Luis E Piñero-Santiago
- Department of Chemistry, University of Puerto Rico at Humacao , Humacao Campus, Humacao, Puerto Rico 00792
| | - María Morel
- Department of Chemistry, University of Puerto Rico , Río Piedras Campus, San Juan, Puerto Rico 00931
| | - Rafael Arce
- Department of Chemistry, University of Puerto Rico , Río Piedras Campus, San Juan, Puerto Rico 00931
| | - Carlos E Crespo-Hernández
- Department of Chemistry, Case Western Reserve University , 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
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25
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Xu C, Yu L, Zhu C, Yu J, Cao Z. Intersystem crossing-branched excited-state intramolecular proton transfer for o-nitrophenol: An ab initio on-the-fly nonadiabatic molecular dynamic simulation. Sci Rep 2016; 6:26768. [PMID: 27221650 PMCID: PMC4879701 DOI: 10.1038/srep26768] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2016] [Accepted: 05/09/2016] [Indexed: 12/26/2022] Open
Abstract
The 6SA-CASSCF(10, 10)/6-31G (d, p) quantum chemistry method has been applied to perform on-the-fly trajectory surface hopping simulation with global switching algorithm and to explore excited-state intramolecular proton transfer reactions for the o-nitrophenol molecule within low-lying electronic singlet states (S0 and S1) and triplet states (T1 and T2). The decisive photoisomerization mechanisms of o-nitrophenol upon S1 excitation are found by three intersystem crossings and one conical intersection between two triplet states, in which T1 state plays an essential role. The present simulation shows branch ratios and timescales of three key processes via T1 state, non-hydrogen transfer with ratio 48% and timescale 300 fs, the tunneling hydrogen transfer with ratios 36% and timescale 10 ps, and the direct hydrogen transfer with ratios 13% and timescale 40 fs. The present simulated timescales might be close to low limit of the recent experiment results.
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Affiliation(s)
- Chao Xu
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Le Yu
- Institute of Molecular Science, Department of Applied Chemistry and Center for Interdisciplinary Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan
- Key Laboratory of Synthetic and Natural Functional Molecule Chemistry of Ministry of Education, The College of Chemistry & Materials Science, Shaanxi key Laboratory of Physico-Inorganic Chemistry, Northwest University, Xi’an 710069, P. R. China
| | - Chaoyuan Zhu
- Institute of Molecular Science, Department of Applied Chemistry and Center for Interdisciplinary Molecular Science, National Chiao Tung University, Hsinchu 30010, Taiwan
- State Key Laboratory for Physical Chemistry of Solid Surfaces and Fujian Provincial Key Lab of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Jianguo Yu
- College of Chemistry, Beijing Normal University, Beijing 100875, P. R. China
| | - Zexing Cao
- State Key Laboratory for Physical Chemistry of Solid Surfaces and Fujian Provincial Key Lab of Theoretical and Computational Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
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26
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Nandi A, Ghosh R, Palit DK. Excited state relaxation pathways of 4-dimethylamino-β-nitrostyrene: Effect of solvent polarity and donor–acceptor conjugation. J Photochem Photobiol A Chem 2016. [DOI: 10.1016/j.jphotochem.2016.02.005] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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27
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Yi J, Xiong Y, Cheng K, Li M, Chu G, Pu X, Xu T. A Combination of Chemometrics and Quantum Mechanics Methods Applied to Analysis of Femtosecond Transient Absorption Spectrum of Ortho-Nitroaniline. Sci Rep 2016; 6:19364. [PMID: 26781083 PMCID: PMC4726040 DOI: 10.1038/srep19364] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 12/11/2015] [Indexed: 12/19/2022] Open
Abstract
A combination of the advanced chemometrics method with quantum mechanics calculation was for the first time applied to explore a facile yet efficient analysis strategy to thoroughly resolve femtosecond transient absorption spectroscopy of ortho-nitroaniline (ONA), served as a model compound of important nitroaromatics and explosives. The result revealed that the ONA molecule is primarily excited to S3 excited state from the ground state and then ultrafast relaxes to S2 state. The internal conversion from S2 to S1 occurs within 0.9 ps. One intermediate state S* was identified in the intersystem crossing (ISC) process, which is different from the specific upper triplet receiver state proposed in some other nitroaromatics systems. The S1 state decays to the S* one within 6.4 ps and then intersystem crossing to the lowest triplet state within 19.6 ps. T1 was estimated to have a lifetime up to 2 ns. The relatively long S* state and very long-lived T1 one should play a vital role as precursors to various nitroaromatic and explosive photoproducts.
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Affiliation(s)
- Jing Yi
- College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Ying Xiong
- Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China
| | - Kemei Cheng
- Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China
| | - Menglong Li
- College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Genbai Chu
- Science and Technology on Plasma Physics Laboratory, Research Center of Laser Fusion, CAEP, Mianyang 621900, People's Republic of China
| | - Xuemei Pu
- College of Chemistry, Sichuan University, Chengdu 610064, People's Republic of China
| | - Tao Xu
- Institute of Chemical Material, China Academy of Engineering Physics (CAEP), Mianyang 621900, People's Republic of China
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28
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Stephansen AB, Larsen MAB, Sølling TI. The involvement of triplet receiver states in the ultrafast excited state processes of small esters. Phys Chem Chem Phys 2016; 18:24484-97. [DOI: 10.1039/c6cp04046b] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
The photoinduced processes of methyl formate and methyl acetate have been probed by femtosecond time-resolved mass spectrometry and photoelectron spectroscopy experiments supported by quantum chemical calculations.
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Affiliation(s)
- A. B. Stephansen
- Department of Chemistry
- Københavns Universitet Det Natur- og Biovidenskabelige Fakultet
- København Ø
- Denmark
| | - M. A. B. Larsen
- Department of Chemistry
- Københavns Universitet Det Natur- og Biovidenskabelige Fakultet
- København Ø
- Denmark
| | - T. I. Sølling
- Department of Chemistry
- Københavns Universitet Det Natur- og Biovidenskabelige Fakultet
- København Ø
- Denmark
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29
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Larsen MAB, Thøgersen J, Stephansen AB, Peon J, Sølling TI, Keiding SR. Transient IR Spectroscopic Observation of Singlet and Triplet States of 2-Nitrofluorene: Revisiting the Photophysics of Nitroaromatics. J Phys Chem A 2015; 120:28-35. [DOI: 10.1021/acs.jpca.5b09125] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Martin A. B. Larsen
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Jan Thøgersen
- Department
of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
| | - Anne B. Stephansen
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Jorge Peon
- Instituto
de Química, Universidad Nacional Autónoma de México, Circuito
Exterior, Ciudad Universitaria 04510, D.F. México
| | - Theis I. Sølling
- Department
of Chemistry, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen Ø, Denmark
| | - Søren R. Keiding
- Department
of Chemistry, Aarhus University, Langelandsgade 140, DK-8000 Aarhus C, Denmark
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30
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Ernst HA, Wolf TJA, Schalk O, González-García N, Boguslavskiy AE, Stolow A, Olzmann M, Unterreiner AN. Ultrafast Dynamics of o-Nitrophenol: An Experimental and Theoretical Study. J Phys Chem A 2015; 119:9225-35. [PMID: 26266823 DOI: 10.1021/acs.jpca.5b04900] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The photolysis of o-nitrophenol (o-NP), a typical push-pull molecule, is of current interest in atmospheric chemistry as a possible source of nitrous acid (HONO). To characterize the largely unknown photolysis mechanism, the dynamics of the lowest lying excited singlet state (S1) of o-NP was investigated by means of femtosecond transient absorption spectroscopy in solution, time-resolved photoelectron spectroscopy (TRPES) in the gas phase and quantum chemical calculations. Evidence of the unstable aci-nitro isomer is provided both in the liquid and in the gas phase. Our results indicate that the S1 state displays strong charge transfer character, which triggers excited state proton transfer from the OH to the NO2 group as evidenced by a temporal shift of 20 fs of the onset of the photoelectron spectrum. The proton transfer itself is found to be coupled to an out-of-plane rotation of the newly formed HONO group, finally leading to a conical intersection between S1 and the ground state S0. In solution, return to S0 within 0.2-0.3 ps was monitored by stimulated emission. As a competitive relaxation channel, ultrafast intersystem crossing to the upper triplet manifold on a subpicosecond time scale occurs both in solution and in the gas phase. Due to the ultrafast singlet dynamics, we conclude that the much discussed HONO split-off is likely to take place in the triplet manifold.
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Affiliation(s)
- Hanna A Ernst
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany
| | - Thomas J A Wolf
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany.,Stanford PULSE Institute, SLAC National Accelerator Laboratory , Menlo Park, California 94025, United States
| | - Oliver Schalk
- AlbaNova University Centre, Stockholm University , Roslagstullsbacken 21, 10691 Stockholm, Sweden.,National Research Council of Canada , 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Núria González-García
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany
| | - Andrey E Boguslavskiy
- National Research Council of Canada , 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada
| | - Albert Stolow
- National Research Council of Canada , 100 Sussex Drive, Ottawa, Ontario K1A 0R6, Canada.,Departments of Chemistry & Physics, University of Ottawa , 10 Marie Curie, Ottawa, Ontario K1N 6N5 Canada
| | - Matthias Olzmann
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany
| | - Andreas-Neil Unterreiner
- Institut für Physikalische Chemie, Karlsruher Institut für Technologie (KIT) , Kaiserstraße 12, 76131 Karlsruhe, Germany
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31
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Richter M, Mai S, Marquetand P, González L. Ultrafast intersystem crossing dynamics in uracil unravelled by ab initio molecular dynamics. Phys Chem Chem Phys 2014; 16:24423-36. [PMID: 25301389 PMCID: PMC4391640 DOI: 10.1039/c4cp04158e] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2014] [Accepted: 10/03/2014] [Indexed: 11/21/2022]
Abstract
Ab initio molecular dynamics simulations have been performed in order to investigate the relaxation dynamics of uracil after UV excitation in gas phase. Intersystem crossing (ISC) has been included for the first time into time-dependent simulations of uracil, allowing the system to relax in the singlet as well as in the triplet states. The results show a qualitatively different picture than similar simulations that include singlet states only. The inclusion of ISC effectively quenches the relaxation to the singlet ground state and instead privileges transitions from the low-lying nπ* state (S1) to a ππ* triplet state (T2) followed by rapid internal conversion to the lowest triplet state.
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Affiliation(s)
- Martin Richter
- Institute of Theoretical Chemistry , Währinger Str. 17 , 1090 Vienna , Austria .
| | - Sebastian Mai
- Institute of Theoretical Chemistry , Währinger Str. 17 , 1090 Vienna , Austria .
| | - Philipp Marquetand
- Institute of Theoretical Chemistry , Währinger Str. 17 , 1090 Vienna , Austria .
| | - Leticia González
- Institute of Theoretical Chemistry , Währinger Str. 17 , 1090 Vienna , Austria .
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32
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Sánchez-Flores EI, Chávez-Calvillo R, Keith TA, Cuevas G, Rocha-Rinza T, Cortés-Guzmán F. Properties of atoms in electronically excited molecules within the formalism of TDDFT. J Comput Chem 2014; 35:820-8. [PMID: 26249171 DOI: 10.1002/jcc.23559] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2013] [Revised: 12/31/2013] [Accepted: 01/19/2014] [Indexed: 11/07/2022]
Abstract
The topological analysis of the electron density for electronic excited states under the formalism of the quantum theory of atoms in molecules using time-dependent density functional theory (TDDFT) is presented. Relaxed electron densities for electronic excited states are computed by solving a Z-vector equation which is obtained by means of the Sternheimer interchange method. This is in contrast to previous work in which the electron density for excited states is obtained using DFT instead of TDDFT, that is, through the imposition of molecular occupancies in accordance with the electron configuration of the excited state under consideration. Once the electron density of the excited state is computed, its topological characterization and the properties of the atoms in molecules are obtained in the same manner that for the ground state. The analysis of the low-lying π→π* singlet and triplet vertical excitations of CO and C6H6 are used as representative examples of the application of this methodology. Altogether, it is shown how this procedure provides insights on the changes of the electron density following photoexcitation and it is our hope that it will be useful in the study of different photophysical and photochemical processes.
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Affiliation(s)
- Eric Iván Sánchez-Flores
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510, D. F. México
| | - Rodrigo Chávez-Calvillo
- Departamento de Física y Química Teórica, Facultad de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510, D. F. México
| | - Todd A Keith
- Semichem, Inc., 12456 West 62nd Terrace, Suite D Shawnee, Kansas, 66216
| | - Gabriel Cuevas
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510, D. F. México
| | - Tomás Rocha-Rinza
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510, D. F. México
| | - Fernando Cortés-Guzmán
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria, México, 04510, D. F. México.,Departamento de Química Teórica, Centro Conjunto de Investigación en Química Sustentable UAEMex-UNAM, Carretera Toluca-Atlacomulco km 14.5, C.P. 50200, Toluca, Mexico
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33
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Haverkate LA, Zbiri M, Johnson MR, Carter E, Kotlewski A, Picken S, Mulder FM, Kearley GJ. Electronic and vibronic properties of a discotic liquid-crystal and its charge transfer complex. J Chem Phys 2014; 140:014903. [DOI: 10.1063/1.4856815] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
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34
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Casas-Solvas JM, Howgego JD, Davis AP. Synthesis of substituted pyrenes by indirect methods. Org Biomol Chem 2014; 12:212-32. [DOI: 10.1039/c3ob41993b] [Citation(s) in RCA: 93] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
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35
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Sølling TI, Kuhlman TS, Stephansen AB, Klein LB, Møller KB. The Non-Ergodic Nature of Internal Conversion. Chemphyschem 2013; 15:249-59. [DOI: 10.1002/cphc.201300926] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2013] [Revised: 11/22/2013] [Indexed: 11/08/2022]
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36
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Mora AK, Murudkar S, Singh PK, Gowthaman N, Mukherjee T, Nath S. Ultrafast excited state dynamics of 1-nitropyrene: Effect of H-bonding. J Photochem Photobiol A Chem 2013. [DOI: 10.1016/j.jphotochem.2013.08.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
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37
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Gutiérrez-Arzaluz L, Guarin CA, Rodríguez-Córdoba W, Peon J. Dynamics of the Formation of a Charge Transfer State in 1,2-Bis(9-anthryl)acetylene in Polar Solvents: Symmetry Reduction with the Participation of an Intramolecular Torsional Coordinate. J Phys Chem B 2013; 117:12175-83. [DOI: 10.1021/jp4038705] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Luis Gutiérrez-Arzaluz
- Instituto
de Química, Universidad Nacional Autónoma de México,
Circuito Exterior, Ciudad Universitaria, México, 04510, D.F., México
| | - Cesar A. Guarin
- Instituto
de Química, Universidad Nacional Autónoma de México,
Circuito Exterior, Ciudad Universitaria, México, 04510, D.F., México
| | - William Rodríguez-Córdoba
- Instituto
de Química, Universidad Nacional Autónoma de México,
Circuito Exterior, Ciudad Universitaria, México, 04510, D.F., México
- Escuela
de Física, Universidad Nacional de Colombia, Sede Medellín, A.A. 3840, Medellín, Colombia
| | - Jorge Peon
- Instituto
de Química, Universidad Nacional Autónoma de México,
Circuito Exterior, Ciudad Universitaria, México, 04510, D.F., México
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38
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López-Arteaga R, Stephansen AB, Guarin CA, Sølling TI, Peon J. The Influence of Push–Pull States on the Ultrafast Intersystem Crossing in Nitroaromatics. J Phys Chem B 2013; 117:9947-55. [DOI: 10.1021/jp403602v] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Affiliation(s)
- Rafael López-Arteaga
- Instituto
de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria,
México, 04510,
D.F., México
| | - Anne B. Stephansen
- Department
of Chemistry, University of Copenhagen,
Universitetsparken 5, DK-2100
Copenhagen Ø, Denmark
| | - Cesar A. Guarin
- Instituto
de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria,
México, 04510,
D.F., México
| | - Theis I. Sølling
- Department
of Chemistry, University of Copenhagen,
Universitetsparken 5, DK-2100
Copenhagen Ø, Denmark
| | - Jorge Peon
- Instituto
de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria,
México, 04510,
D.F., México
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39
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Dias FB, Bourdakos KN, Jankus V, Moss KC, Kamtekar KT, Bhalla V, Santos J, Bryce MR, Monkman AP. Triplet harvesting with 100% efficiency by way of thermally activated delayed fluorescence in charge transfer OLED emitters. ADVANCED MATERIALS (DEERFIELD BEACH, FLA.) 2013; 25:3707-3714. [PMID: 23703877 DOI: 10.1002/adma.201300753] [Citation(s) in RCA: 408] [Impact Index Per Article: 37.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/15/2013] [Revised: 04/19/2013] [Indexed: 06/02/2023]
Abstract
Organic light-emitting diodes (OLEDs) have their performance limited by the number of emissive singlet states created upon charge recombination (25%). Recently, a novel strategy has been proposed, based on thermally activated up-conversion of triplet to singlet states, yielding delayed fluorescence (TADF), which greatly enhances electroluminescence. The energy barrier for this reverse intersystem crossing mechanism is proportional to the exchange energy (ΔEST ) between the singlet and triplet states; therefore, materials with intramolecular charge transfer (ICT) states, where it is known that the exchange energy is small, are perfect candidates. However, here it is shown that triplet states can be harvested with 100% efficiency via TADF, even in materials with ΔEST of more than 20 kT (where k is the Boltzmann constant and T is the temperature) at room temperature. The key role played by lone pair electrons in achieving this high efficiency in a series of ICT molecules is elucidated. The results show the complex photophysics of efficient TADF materials and give clear guidelines for designing new emitters.
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Affiliation(s)
- Fernando B Dias
- Durham University, Physics Department, Rochester Building, South Road, DH1 3LE, UK.
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40
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Vogt RA, Reichardt C, Crespo-Hernández CE. Excited-State Dynamics in Nitro-Naphthalene Derivatives: Intersystem Crossing to the Triplet Manifold in Hundreds of Femtoseconds. J Phys Chem A 2013; 117:6580-8. [DOI: 10.1021/jp405656n] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
Affiliation(s)
- R. Aaron Vogt
- Department of Chemistry, Center
for Chemical Dynamics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Christian Reichardt
- Department of Chemistry, Center
for Chemical Dynamics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
| | - Carlos E. Crespo-Hernández
- Department of Chemistry, Center
for Chemical Dynamics, Case Western Reserve University, 10900 Euclid Avenue, Cleveland, Ohio 44106, United States
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41
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Gutiérrez-Meza E, Noria R, Granados G, Gómez-Vidales V, Ramírez JZ, Beltrán HI, Peon J. Photophysics of a cis axially disubstituted macrocycle: rapid intersystem crossing in a tin(IV) phthalocyanine with a half-domed geometry. J Phys Chem B 2012; 116:14107-14. [PMID: 23106168 DOI: 10.1021/jp3078453] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
We have studied the photophysical properties of a tin(IV) phthalocyanine which coordinates two myristate groups through their carboxylate functionalities in a cis disposition at the tin center. Such a coordination mode, anisobidentate through the same side of the macrocycle, makes this phthalocyanine acquire a capped or half-domed shape. This bis myristate tin(IV) molecule shows an intersystem crossing channel which populates the triplet manifold with high efficiency and with a time constant of 300 ps, about an order of magnitude faster than planar phthalocyanines, including some previously reported tin(IV) phthalocyanines. For comparison purposes, we also include the description of a planar silicon(IV) phthalocyanine that keeps the more common stereochemistry, of trans type, with the same axial myristate groups. The characterization of these systems included steady state and time-resolved spectroscopy through femtosecond fluorescence up-conversion and transient absorption. We also studied the initial S(n) → S(1) internal conversion dynamics when these compounds are excited to upper states with 387.5 nm light. In addition, we include measurements of the rate for singlet oxygen production through the formation of an ESR-active adduct in aerated solutions. Such measurements indicate that, associated to its photophysics, the tin(IV) phthalocyanine produces (1)O(2) with an efficiency significantly larger than the silicon(IV) counterpart, making it an interesting option for sensitization applications. Finally, we performed excited state calculations at the TD-DFT level which describe the effects of the reduced symmetry together with the state ordering and indicate the presence of near dark intermediate states between the Q and B transitions for both of these macrocycles.
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Affiliation(s)
- Elizabeth Gutiérrez-Meza
- Universidad Nacional Autónoma de México , Instituto de Química, Ciudad Universitaria, México, DF, México
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42
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Villabona-Monsalve JP, Noria R, Matsika S, Peón J. On the Accessibility to Conical Intersections in Purines: Hypoxanthine and its Singly Protonated and Deprotonated Forms. J Am Chem Soc 2012; 134:7820-9. [DOI: 10.1021/ja300546x] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Juan. P. Villabona-Monsalve
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria,
México, 04510,
D.F., México
| | - Raquel Noria
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria,
México, 04510,
D.F., México
| | - Spiridoula Matsika
- Department
of Chemistry, Temple University, 13th and
Norris Streets, Philadelphia
Pennsylvania 19122, United States
| | - Jorge Peón
- Instituto de Química, Universidad Nacional Autónoma de México, Circuito Exterior, Ciudad Universitaria,
México, 04510,
D.F., México
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43
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García-Berríos ZI, Arce R. Photodegradation mechanisms of 1-nitropyrene, an environmental pollutant: the effect of organic solvents, water, oxygen, phenols, and polycyclic aromatics on the destruction and product yields. J Phys Chem A 2012; 116:3652-64. [PMID: 22458822 PMCID: PMC3334876 DOI: 10.1021/jp2126416] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
This work describes studies of the photodegradation mechanism of 1-nitropyrene (1-NO(2)Py) in a chemical model system consisting of an organic solvent and known constituents of an aerosol particle. Photoproducts such as 1-hydroxypyrene (1-OHPy), 1-hydroxy-x-nitropyrenes (1-OH-x-NO(2)Py), 1-nitrosopyrene, and 1,6- and 1,8-pyrenediones were identified by high-performance liquid chromatography (HPLC) and HPLC/mass spectrometry (HPLC/MS) techniques, and their quantum yields show a significant dependence on the type of solvent. The photodegradation quantum yield of 1-NO(2)Py, φ((-1-NO2Py)), was larger in toluene, benzene, and polar protic solvents (10(-3)) in comparison with nonpolar and polar aprotic solvents, where the yield is on the order of 10(-4). In solvents with an abstractable hydrogen atom, the products formed in higher yields were 1-OHPy and 1-OH-x-NO(2)Py. These represent 60-80% of the photodestruction yield and result from abstraction and recombination reactions of the pyrenoxy radical, an intermediate postulated to be formed as a result of a nitro-nitrite rearrangement in nitroaromatics. The small O(2) effect in the photodegradation yield and the quenching experiments with azulene demonstrate the small contribution of the (3)(π,π*) state in the 1-NO(2)Py photoreaction. The nitrosopyrene product was not observed under these conditions, demonstrating the participation of the (3)(π,π*) state in its formation. In the presence various phenol aerosol constituents, the photodegradation yield increased by 10-fold in all solvents. This effect is partly ascribed to the reaction of the (3)(π,π*) state with the phenol. The effect of water resulted in the reduction of the 1-NO(2)Py photodegradation yield and of its photoproducts. The phototodegradation of 1-NO(2)Py was also studied in a viscous solvent, hexadecane, and it was determined that this medium does not inhibit its photodecay.
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Affiliation(s)
- Zulma I. García-Berríos
- Department of Chemistry, University of Puerto Rico, Río Piedras Campus, San Juan, Puerto Rico, 00931-3346
| | - Rafael Arce
- Department of Chemistry, University of Puerto Rico, Río Piedras Campus, San Juan, Puerto Rico, 00931-3346
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44
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Schmierer T, Ryseck G, Villnow T, Regner N, Gilch P. Kasha or state selective behavior in the photochemistry of ortho-nitrobenzaldehyde? Photochem Photobiol Sci 2012; 11:1313-21. [DOI: 10.1039/c2pp25057h] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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45
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Murudkar S, Mora AK, Singh PK, Nath S. Origin of ultrafast excited state dynamics of 1-nitropyrene. J Phys Chem A 2011; 115:10762-6. [PMID: 21861515 DOI: 10.1021/jp205946c] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Time-resolved emission measurements in subpicosecond time domain have been carried out for 1-nitropyrene in different solvents to understand the mechanism for the observed ultrafast decay of its first excited singlet state. Excited-state dynamics of 1-nitropyrene is found to be independent of the solvent viscosity. This result contradicts the proposition in the literature (J. Phys. Chem. A 2007, 111, 552) that the ultrafast decay in 1-nitropyrene is due to the large amplitude torsional motion of the nitro group around the pyrene moiety. Excited-state dynamics of 1-nitropyrene in solvents with different dielectric constants shows that excited-state lifetime suddenly increases after a certain value of the dielectric constant. Detailed quantum chemical calculations have been carried out to understand the process that is responsible for the observed effect of the dielectric constant on the excited-state dynamics of 1-nitropyrene. It is seen that the excited-state lifetime and the singlet-triplet energy gap follow similar variation with the dielectric constant of the medium. Such a correlation between the excited-state lifetime and the singlet-triplet energy gap supports the fact that the observed ultrafast decay for 1-nitropyrene is due to an efficient intersystem crossing rather than to the torsional motion of the nitro group as proposed in the literature.
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Affiliation(s)
- Sushant Murudkar
- Radiation & Photochemistry Division, Bhabha Atomic Research Centre, Trombay, Mumbai 400 085, India
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