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Phenylene-linked tetrapyrrole arrays containing free base and diverse metal chelate forms – Versatile synthetic architectures for catalysis and artificial photosynthesis. Coord Chem Rev 2022. [DOI: 10.1016/j.ccr.2021.214278] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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2
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Poddutoori PK, Kandrashkin YE, Karr P, van der Est A. Electron spin polarization in an Al(III) porphyrin complex with an axially bound nitroxide radical. J Chem Phys 2019; 151:204303. [DOI: 10.1063/1.5127760] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Prashanth K. Poddutoori
- Department of Chemistry and Biochemistry, University of Minnesota Duluth, Duluth, Minnesota 55812, USA
| | - Yuri E. Kandrashkin
- Zavoisky Physical-Technical Institute, FRC Kazan Scientific Center of RAS, Sibirsky Tract 10/7, Kazan 420029, Russia
| | - Paul Karr
- Department of Physical Sciences and Mathematics, Wayne State College, Wayne, Nebraska 68787, USA
| | - Art van der Est
- Department of Chemistry Brock University, St. Catharines Ontario L2S 3A1, Canada
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3
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Fushimi Y, Koinuma M, Yasuda Y, Nomura K, Asano MS. Effects of End-Groups on Photophysical Properties of Poly(9,9-di-n-octylfluorene-2,7-vinylene)s Linked with Metalloporphyrins: Synthesis and Time-Resolved Fluorescence Spectroscopy. Macromolecules 2017. [DOI: 10.1021/acs.macromol.7b00047] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Affiliation(s)
- Yasutaka Fushimi
- Department
of Chemistry, Faculty of Science and Engineering, Tokyo Metropolitan University, 1-1 minami
Osawa, Hachioji, Tokyo 192-0397, Japan
| | - Misaki Koinuma
- Division
of Molecular Science, Faculty of Science and Engineering, Gunma University, 1-5-1
Tenjin-cho, Kiryu, Gunma 376-8515, Japan
| | - Yoshifumi Yasuda
- Division
of Molecular Science, Faculty of Science and Engineering, Gunma University, 1-5-1
Tenjin-cho, Kiryu, Gunma 376-8515, Japan
| | - Kotohiro Nomura
- Department
of Chemistry, Faculty of Science and Engineering, Tokyo Metropolitan University, 1-1 minami
Osawa, Hachioji, Tokyo 192-0397, Japan
| | - Motoko S. Asano
- Division
of Molecular Science, Faculty of Science and Engineering, Gunma University, 1-5-1
Tenjin-cho, Kiryu, Gunma 376-8515, Japan
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4
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Asano MS, Okamura K, Fujii T, Otsuka T, Kaizu Y. Enhanced Intersystem Crossing Due to Long-range Exchange Interaction in Porphyrin Heterodimers: Dependence of Paramagnetic Species. CHEM LETT 2014. [DOI: 10.1246/cl.131096] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
| | | | - Takeshi Fujii
- Department of Chemistry, Tokyo Institute of Technology
| | | | - Youkoh Kaizu
- Department of Chemistry, Tokyo Institute of Technology
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5
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Asano MS, Okamura K, Jin-mon A, Takahashi S, Kaizu Y. Enhanced intersystem crossing due to long-range exchange interaction in copper(II) porphyrin-free base porphyrin dimers: HOMO and spacer dependence. Chem Phys 2013. [DOI: 10.1016/j.chemphys.2013.03.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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6
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Poddutoori PK, Dion A, Yang S, Pilkington M, Wallis JD, van der Est A. Light-induced hole transfer in a hypervalent phosphorus(V) octaethylporphyrin bearing an axially linked bis(ethylenedithio)tetrathiafulvalene. J PORPHYR PHTHALOCYA 2012. [DOI: 10.1142/s108842461000191x] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
A phosphorus(V) porphyrin bearing an axially linked bis(ethylenedithio)tetrathiafulvalene, dyad 1, and its radical cation phosphorus(V) porphyrin- O-CH2 -(bis(ethylenedithio)tetrathiafulvalene)+•, dyad 2, have been synthesized and studied as an electron hole donor-acceptor system. The absorption spectrum of dyad 1 does not show evidence for electronic coupling between the porphyrin and the bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) moieties. However, the steady-state fluorescence of the porphyrin chromophore is quantitatively quenched and its transient fluorescence lifetime is shortened compared to a reference compound in which the BEDT-TTF moiety is replaced by a methoxy group. Chemical oxidation of the BEDT-TTF moiety in dyad 1 to give dyad 2 results in recovery of the fluorescence intensity. This behavior suggests that the fluorescence quenching in dyad 1 is the result of intramolecular hole transfer from the the excited porphyrin to the BEDT-TTF moiety. The occurence of hole transfer in dyad 1 is confirmed by freeze-trapping and time-resolved electron paramagnetic resonance (EPR) measurements. The freeze-trapping EPR experiments show that steady-state irradiation of the complex leads to accumulation of its radical cation (dyad 2) while the transient EPR measurements at 5 °C show that flash irradiation of dyad 1 results in formation of a radical-ion pair with a lifetime of at least 300 ns. The triplet state of the porphyrin, which is formed by intersystem crossing and gives a strong transient EPR spectrum in the reference compound, is not observed for dyad 1. Together, the fluorescence quenching and the polarization pattern of the radical pair suggest that the hole transfer occurs from the excited singlet state of the porphyrin with high efficiency.
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Affiliation(s)
- Prashanth K. Poddutoori
- Department of Chemistry, Brock University, 500 Glenridge Ave., St. Catharines, ON L2S 3A1, Canada
| | - Ann Dion
- Department of Chemistry, Brock University, 500 Glenridge Ave., St. Catharines, ON L2S 3A1, Canada
| | - Songjie Yang
- School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, United Kingdom
| | - Melanie Pilkington
- Department of Chemistry, Brock University, 500 Glenridge Ave., St. Catharines, ON L2S 3A1, Canada
| | - John D. Wallis
- School of Science and Technology, Nottingham Trent University, Clifton Lane, Nottingham NG11 8NS, United Kingdom
| | - Art van der Est
- Department of Chemistry, Brock University, 500 Glenridge Ave., St. Catharines, ON L2S 3A1, Canada
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TOYAMA NAMIKI, ASANO-SOMEDA MOTOKO, KAIZU YOUKOH. EPR spectra of gable-type copper(II) porphyrin dimers in fluid solution: extraction of exchange interaction in weakly coupled doublet pairs. Mol Phys 2009. [DOI: 10.1080/0026897021000054808] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Affiliation(s)
- NAMIKI TOYAMA
- a Department of Chemistry , Tokyo Institute of Technology , O-okayama, Meguro-ku , Tokyo , 152-8551 , Japan
| | - MOTOKO ASANO-SOMEDA
- a Department of Chemistry , Tokyo Institute of Technology , O-okayama, Meguro-ku , Tokyo , 152-8551 , Japan
| | - YOUKOH KAIZU
- a Department of Chemistry , Tokyo Institute of Technology , O-okayama, Meguro-ku , Tokyo , 152-8551 , Japan
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8
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Severino D, Junqueira HC, Gugliotti M, Gabrielli DS, Baptista MS. Influence of Negatively Charged Interfaces on the Ground and Excited State Properties of Methylene Blue ¶. Photochem Photobiol 2007. [DOI: 10.1562/0031-8655(2003)0770459ioncio2.0.co2] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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9
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Benniston AC, Harriman A, Li P, Rostron JP, van Ramesdonk HJ, Groeneveld MM, Zhang H, Verhoeven JW. Charge Shift and Triplet State Formation in the 9-Mesityl-10-methylacridinium Cation. J Am Chem Soc 2005; 127:16054-64. [PMID: 16287292 DOI: 10.1021/ja052967e] [Citation(s) in RCA: 131] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The target donor-acceptor compound forms an acridinium-like, locally excited (LE) singlet state on illumination with blue or near-UV light. This LE state undergoes rapid charge transfer from the acridinium ion to the orthogonally sited mesityl group in polar solution. The resultant charge-transfer (CT) state fluoresces in modest yield and decays on the nanosecond time scale. The LE and CT states reside in thermal equilibrium at ambient temperature; decay of both states is weakly activated in fluid solution, but decay of the CT state is activationless in a glassy matrix. Analysis of the fluorescence spectrum allows precise location of the relevant energy levels. Intersystem crossing competes with radiative and nonradiative decay of the CT state such that an acridinium-like, locally excited triplet state is formed in both fluid solution and a glassy matrix. Phosphorescence spectra position the triplet energy well below that of the CT state. The triplet decays via first-order kinetics with a lifetime of ca. 30 micros at room temperature in the absence of oxygen but survives for ca. 5 ms in an ethanol glass at 77 K. The quantum yield for formation of the LE triplet state is 0.38 but increases by a factor of 2.3-fold in the presence of iodomethane. The triplet reacts with molecular oxygen to produce singlet molecular oxygen in high quantum yield. In sharp contradiction to a recent literature report, there is no spectroscopic evidence to indicate the presence of an unusually long-lived CT state.
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Affiliation(s)
- Andrew C Benniston
- Molecular Photonics Laboratory, School of Natural Science, University of Newcastle, Newcastle upon Tyne, NE1 7RU, United Kingdom
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Faure S, Stern C, Espinosa E, Douville J, Guilard R, Harvey PD. Triplet-Triplet Energy Transfer Controlled by the Donor-Acceptor Distance in Rigidly Held Palladium-Containing Cofacial Bisporphyrins. Chemistry 2005; 11:3469-81. [PMID: 15812878 DOI: 10.1002/chem.200400990] [Citation(s) in RCA: 54] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Eleven new complexes, including mono-, heterobi-, and homobimetallic cofacial bisporphyrins, (Pd)H2DPS, (M)H2DPX, (M)H2DPB, (PdZn)DPS, (PdZn)DPX, (Pt)2DPX, (M)2DPB (M = Pd, Pt), and (Pt)P (DPS4- = 4,6-bis[5-(2,8,13,17-tetraethyl-3,7,12,18-tetramethylporphyrinyl)]dibenzothiophene tetraanion, DPX(4-) = 4,5-bis[5-(2,8,13,17-tetraethyl-3,7,12,18-tetramethylporphyrinyl)]-9,9-dimethylxanthene tetraanion, DPB4- = 1,8-bis[5-(2,8,13,17-tetraethyl-3,7,12,18-tetramethylporphyrinyl)]biphenylene tetraanion, P2- = 5-phenyl-2,8,13,17-tetraethyl-3,7,12,18-tetramethylporphyrin dianion) have been synthesized and characterized. The photophysical properties of the donor (M)P (M=Pd or Pt, P=porphyrin chromophore) and the acceptor (free base H(2)P or (Zn)P) depend on the C(meso)-C(meso) distance and the presence of a heavy atom such as Pd(II) or Pt(II). The data were compared with those for the known compounds (Pd)2DPS, (Pd)2DPX, H4DPS, H4DPX, H4DPB, (Pd)P, (Zn)P, and H(2)P. The rate constants for triplet-triplet energy transfer (k(ET)) were measured for the heterobimetallic (PdZn) and monometallic [(M)H2] derivatives (M=Pd, Pt). The fluorescence lifetimes (Deltatau(F)) of the acceptors decrease as a result of the heavy-atom effect, and vary as follows: (Pd)H2DPS<<(Pd)H2DPX approximately (Pd)H2DPB. The k(ET) values calculated according to the equation k(ET)=(1/tau(emi)-1/tau(emi) (0)), where tau(emi) (0) is the emission lifetime of the homobimetallic bisporphyrins (no ET occurs), are equal to 0, 247+/-57 and 133+/-52 s(-1) for DPS, DPX, and DPB, respectively, in the (Pd)H(2) series. These measurements allowed the range of distance over which the Dexter mechanism for T(1)-T(1) energy transfer ceases to operate to be determined. This distance is somewhere between 4.3 and 6.3 A, in agreement with our recent findings on singlet-singlet energy transfer. During the course of this study, the X-ray crystal structure for (Pd)H2DPX was obtained; triclinic (P1), a = 11.1016(1), b = 14.9868(2), c = 20.6786(3) A, alpha = 102.091(1), beta = 100.587(1), gamma = 101.817(1) degrees , V = 3199.19(7) A(3), Z = 2.
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Affiliation(s)
- Sébastien Faure
- LIMSAG UMR 5633, Université de Bourgogne, 6 bd Gabriel, 21100 Dijon, France
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11
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Pettersson K, Kilså K, Mårtensson J, Albinsson B. Intersystem Crossing versus Electron Transfer in Porphyrin-Based Donor−Bridge−Acceptor Systems: Influence of a Paramagnetic Species. J Am Chem Soc 2004; 126:6710-9. [PMID: 15161299 DOI: 10.1021/ja0370488] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have investigated how the spin state of an acceptor influences the photophysical processes in a donor-bridge-acceptor (D-B-A) system. The system of choice has zinc porphyrin as the electron donor and high- or low-spin iron(III) porphyrin as the acceptor. The spin state of the acceptor porphyrin is switched simply by coordinating imidazole ligands to the metal center. The D-A center-center distance is 26 A, and the bridging chromophore varies from pi-conjugated to a sigma-bonded system. The presence of a high-spin iron(III) porphyrin in such systems has previously been shown to significantly enhance intersystem crossing in the remote zinc porphyrin donor, whereas no significant electron transfer to the iron porphyrin acceptor was observed, even though the thermodynamics would allow for photoinduced electron transfer. Here, we demonstrate that by switching the acceptor to a low-spin state, the dominating photophysical process is drastically changed; the low-spin system shows long-range electron transfer on the picosecond time-scale, and intersystem crossing occurs at its "normal" rate.
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Affiliation(s)
- Karin Pettersson
- Department of Chemistry and Bioscience, Chalmers University of Technology, SE-412 96 Göteborg, Sweden
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Kandrashkin Y, Van Der Est A. Electron spin polarization of the excited quartet state of strongly coupled triplet–doublet spin systems. J Chem Phys 2004; 120:4790-9. [PMID: 15267339 DOI: 10.1063/1.1645773] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The electron spin polarization associated with electronic relaxation in molecules with trip-quartet and trip-doublet excited states is calculated. Such molecules typically relax to the lowest trip-quartet state via intersystem crossing from the trip doublet, and it is shown that when spin-orbit coupling provides the main mechanism for this relaxation pathway it leads to spin polarization of the trip quartet. Analytical expressions for this polarization are derived using first- and second-order perturbation theory and are used to calculate powder spectra for typical sets of magnetic parameters. It is shown that both net and multiplet contributions to the polarization occur and that these can be separated in the spectrum as a result of the different orientation dependences of the +/-1/2<-->+/-3/2 and +1/2<-->-1/2 transitions. The net polarization is found to be localized primarily in the center of the spectrum, while the multiplet contribution dominates in the outer wings. Despite the fact that the multiplet polarization is much stronger than the net polarization for individual orientations of the spin system, the difference in orientation dependence of the transitions leads to comparable amplitudes for the two contributions in the powder spectrum. The influence of this difference on the line shape is investigated in simulations of partially ordered samples. Because the initial nonpolarized state of the spin system is not conserved for the proposed mechanism, the net polarization can survive in the doublet ground state following electronic relaxation of the triplet part of the system.
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Affiliation(s)
- Yuri Kandrashkin
- Department of Chemistry, Brock University, 500 Glenridge Avenue, St. Catharines, Ontario, Canada
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Severino D, Junqueira HC, Gugliotti M, Gabrielli DS, Baptista MS. Influence of negatively charged interfaces on the ground and excited state properties of methylene blue. Photochem Photobiol 2003; 77:459-68. [PMID: 12812286 DOI: 10.1562/0031-8655(2003)077<0459:ioncio>2.0.co;2] [Citation(s) in RCA: 123] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Properties of the ground and excited states of methylene blue (MB) were studied in negatively charged vesicles, normal and reverse micelles and sodium chloride solutions. All these systems induce dimer formation as attested by the appearance of the dimer band in the absorption spectra (lamdaD approximately 600 nm). In reverse micelles the dimerization constant (KD) corrected for the aqueous pseudophase volume fraction is two-three orders of magnitude smaller than KD of MB in water, and it does not change when W0 is increased from 0.5 to 10. Differences in the fluorescence intensity as a function of dimer-monomer ratio as well as in the resonance light scattering spectra indicate that distinct types of dimers are induced in sodium dodecyl sulfate (SDS) micelles and aerosol-OT (sodium dioctyl sulfoxinate, AOT) reversed micelles. The properties of the photoinduced transient species of MB in these systems were studied by time-resolved near infrared (NIR) emission (efficiency of singlet oxygen generation), by laser flash photolysis (transient spectra, yield and decay rate of triplets) and by thermal lensing (amount of heat deposited in the medium). The competition between electron transfer (dye*-dye) and energy transfer (dye*-O2) reactions was accessed as a function of the dimer-monomer ratio. The lower yield of electron transfer observed for dimers in AOT reverse micelles and intact vesicles compared with SDS micelles and frozen vesicles at similar dimer-monomer ratios is related with the different types of aggregates induced by each interface.
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Affiliation(s)
- Divinomar Severino
- Departamento de Bioquímica, Instituto de Química, Universidade de São Paulo, São Paulo, Brazil
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