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Glotz G, Püschmann S, Haas M, Gescheidt G. Direct detection of photo-induced reactions by IR: from Brook rearrangement to photo-catalysis. Photochem Photobiol Sci 2023:10.1007/s43630-023-00406-4. [PMID: 36933157 DOI: 10.1007/s43630-023-00406-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 02/28/2023] [Indexed: 03/19/2023]
Abstract
In situ IR detection of photoreactions induced by the light of LEDs at appropriate wavelengths provides a simple, cost-effective, and versatile method to get insight into mechanistic details. In particular, conversions of functional groups can be selectively followed. Overlapping UV-Vis bands or fluorescence from the reactants and products and the incident light do not obstruct IR detection. Compared with in situ photo-NMR, our setup does not require tedious sample preparation (optical fibers) and offers a selective detection of reactions, even at positions where 1H-NMR lines overlap or 1H resonances are not clear-cut. We illustrate the applicability of our setup following the photo-Brook rearrangement of (adamant-1-yl-carbonyl)-tris(trimethylsilyl)silane, address photo-induced α-bond cleavage (1-hydroxycyclohexyl phenyl ketone), study photoreduction using tris(bipyridine)ruthenium(II), investigate photo-oxygenation of double bonds with molecular oxygen and the fluorescent 2,4,6-triphenylpyrylium photocatalyst, and address photo-polymerization. With the LED/FT-IR combination, reactions can be qualitatively followed in fluid solution, (highly) viscous environments, and in the solid state. Viscosity changes during the reaction (e.g., during a polymerization) do not obstruct the method.
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Affiliation(s)
- Gabriel Glotz
- Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremayrgasse 9/II, 8010, Graz, Austria.
| | - Sabrina Püschmann
- Institute of Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9/IV, 8010, Graz, Austria
| | - Michael Haas
- Institute of Inorganic Chemistry, Graz University of Technology, Stremayrgasse 9/IV, 8010, Graz, Austria
| | - Georg Gescheidt
- Institute of Physical and Theoretical Chemistry, Graz University of Technology, Stremayrgasse 9/II, 8010, Graz, Austria
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2
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Photoinduced Electron Transfer Reactions of Water Soluble Porphyrins in Zeolite Environment. J Fluoresc 2021; 31:1575-1585. [PMID: 34338967 DOI: 10.1007/s10895-021-02747-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2021] [Accepted: 05/04/2021] [Indexed: 10/20/2022]
Abstract
Excited state interactions of zeolite adsorbed porphyrins have been investigated by steady state luminescence quenching technique with certain antioxidants such as reduced glutathione, ascorbic acid and L-cysteine. The zeolite supported porphyrins, meso-tetra (N-methyl-4-pyridyl) porphyrin (H2TMPyP4+) and zinc tetra(N-methyl-4-pyridyl) porphyrin (ZnTMPyP4+) were prepared and characterized by various techniques such as Diffuse Reflectance Spectra (DRS), Scanning Electron Microscope (SEM), powder X-Ray Diffraction (XRD) and BET surface area. The interaction of zeolites with porphyrins are shown to increase the lifetime of the singlet excited state of porphyrins and decays are biphasic in nature. The splitting of the emission band of porphyrins occurs in 1:1 glycerol: water solution due to the changes in the dielectric of the solvation sphere associated with porphyrin. The Stern-Volmer plots of I0/I vs quencher concentration [Q] were linear in the whole range of [Q] used. These studies revealed the effective quenching for zinc porphyrin compared to free base porphyrin. The effect of quenchers and zeolite acidity has also been studied and the quenching rate constant (kq) is found in the order of 109 M-1 s-1. The quenching reaction obeys Rehm-Weller Equation and is shown to be due to thermodynamically favoured electron transfer from quenchers to the excited singlet state of porphyrins (reductive quenching).
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Awwad N, Bui AT, Danilov EO, Castellano FN. Visible-Light-Initiated Free-Radical Polymerization by Homomolecular Triplet-Triplet Annihilation. Chem 2020. [DOI: 10.1016/j.chempr.2020.08.019] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
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Valarmathy G, Subbalakshmi R, Sumathi R, Renganathan R. Synthesis of Schiff base ligand from N-substituted benzenesulfonamide and its complexes: Spectral, thermal, electrochemical behavior, fluorescence quenching, in vitro-biological and in-vitro cytotoxic studies. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2019.127029] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Abdelbar MF, Fayed TA, Meaz TM, Subramani T, Fukata N, Ebeid EZM. Hybrid organic and inorganic solar cell based on a cyanine dye and quantum dots. J Photochem Photobiol A Chem 2019. [DOI: 10.1016/j.jphotochem.2019.01.023] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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6
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Vellaiswamy G, Ramaswamy S. Co(II) Complexes of4-((3-ethoxy-2-hydroxybenzylidene)amino)-N-(thiazol-2-yl)benzenesulphonamide and 4-((pyridin-2-ylmethylene)amino)-N-(thiazol-2-tl)benzenesulfonamide: Synthesis, Fluorescence Properties and Anticancer Activity. J Fluoresc 2017; 27:1559-1565. [PMID: 28447182 DOI: 10.1007/s10895-017-2096-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 04/04/2017] [Indexed: 11/24/2022]
Abstract
Two new Co(II) complexes of 4-((3-ethoxy-2-hydroxybenzylidene)amino)-N-(thiazol-2-yl)benzenesulphonamide and 4-((pyridin-2-ylmethylene)amino)-N-(thiazol-2-yl)benzene sulfonamide were synthesised. The structure of the complexes was identified by elemental analysis, FT-IR, electronic, EI mass, Powder XRD spectra and magnetic moment. The TG and DTA patterns of the complexes were supported the structures. The fluorescence quenching of these complexes with alizarin dye were premeditated and the free energy change (∆Get) for electron transfer process was designed by Rehm-Weller equation. The [Co(L1-H)2(H2O)2] and [Co(L2)2(H2O)2].2H2O were submitted for in vitro cytotoxicity studies in human breast cancer cell line (MCF 7).
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Affiliation(s)
- Gomathi Vellaiswamy
- PG and Research Department of Chemistry, Seethalakshmi Ramaswami College, Tiruchirappalli, Tamil Nadu, 620 002, India.
| | - Selvameena Ramaswamy
- PG and Research Department of Chemistry, Seethalakshmi Ramaswami College, Tiruchirappalli, Tamil Nadu, 620 002, India
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Abdelbar MF, Fayed TA, Meaz TM, Ebeid EZM. Photo-induced interaction of thioglycolic acid (TGA)-capped CdTe quantum dots with cyanine dyes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2016; 168:1-11. [PMID: 27267278 DOI: 10.1016/j.saa.2016.05.029] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/08/2015] [Revised: 12/19/2015] [Accepted: 05/22/2016] [Indexed: 06/06/2023]
Abstract
The photo-induced interaction of three different sizes of thioglycolic acid (TGA)-capped CdTe quantum dots (CdTe QDs) with two monomethine cyanine dyes belonging to the thiazole orange (TO) family has been studied. Positively charged cyanines interact with QDs surface which is negatively charged due to capping agent carboxylate ions. The energy transfer parameters including Stern-Volmer constant, Ksv, number of binding sites, n, quenching sphere radius, r, the critical energy transfer distance, R0, and energy transfer efficiencies, E have been calculated. The effect of structure and the number of aggregating molecules have been studied as a function of CdTe QDs particle size. Combining organic and inorganic semiconductors leads to increase of the effective absorption cross section of the QDs which can be utilized in novel nanoscale designs for light-emitting, photovoltaic and sensor applications. A synthesized triplet emission of the studied dyes was observed using CdTe QDs as donors and this is expected to play a potential role in molecular oxygen sensitization and in photodynamic therapy (PDT) applications.
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Affiliation(s)
- Mostafa F Abdelbar
- Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt
| | - Tarek A Fayed
- Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt
| | - Talaat M Meaz
- Physics Department, Faculty of Science, Tanta University, Tanta, Egypt
| | - El-Zeiny M Ebeid
- Chemistry Department, Faculty of Science, Tanta University, Tanta, Egypt; Misr University for Science and Technology (MUST), 6th of October City, Egypt
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RETRACTED ARTICLE: Site Specific Interaction Between TiO2 Nanoparticles and Phenanthrimidazole—A First Principles Quantum Mechanical Study. J Fluoresc 2015; 25:1063-83. [DOI: 10.1007/s10895-015-1593-2] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2015] [Accepted: 06/04/2015] [Indexed: 10/23/2022]
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Jayabharathi J, Karunakaran C, Ramanathan P. Binding interaction between 2-(naphthalen-1-yl)-1-p-tolyl-1H-phenanthro[9,10-d]imidazole and semiconductor nanomaterials. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2015; 136 Pt C:1428-1433. [PMID: 25459702 DOI: 10.1016/j.saa.2014.10.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/31/2014] [Revised: 07/04/2014] [Accepted: 10/13/2014] [Indexed: 06/04/2023]
Abstract
The binding interaction of bioactive phenanthrimidazole with nanoparticulate WO3, Fe2O3, Fe3O4, CuO, ZrO2 and Al2O3 has been studied by electronic and life time spectral studies. The phenanthrimidazole adsorbs strongly on the surface of nanosemiconductor, the apparent binding constants have been determined from the fluorescence quenching. In the case of nanocrystalline insulator, fluorescence quenching through electron transfer from the excited state of the phenanthrimidazole to alumina is not possible, but it is due to energy transfer process.
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Affiliation(s)
- J Jayabharathi
- Department of Chemistry, Annamalai University, Annamalainagar 608002, Tamil Nadu, India.
| | - C Karunakaran
- Department of Chemistry, Annamalai University, Annamalainagar 608002, Tamil Nadu, India
| | - P Ramanathan
- Department of Chemistry, Annamalai University, Annamalainagar 608002, Tamil Nadu, India
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Jayabharathi J, Sundharesan M, Prabhakaran A, Karunakaran C. Understanding the binding interaction of imidazole with ZnO nanomaterials and clusters. RSC Adv 2015. [DOI: 10.1039/c4ra15957h] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
The order of binding energy values for imidazole adsorbed ZnO clusters through the preferred azomethine nitrogen site is imidazole–Zn4O4 (R) > imidazole–Zn3O3 > imidazole–Zn4O4 (W) > imidazole–Zn2O2.
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11
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Jayabharathi J, Arunpandiyan A, Thanikachalam V, Ramanathan P. Photoinduced Electron Transfer from Phenanthrimidazole to Magnetic Nanoparticles. J Fluoresc 2015; 25:137-45. [DOI: 10.1007/s10895-014-1490-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2014] [Accepted: 12/02/2014] [Indexed: 10/24/2022]
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Jayabharathi J, Karunakaran C, Kalaiarasi V. Thermodynamically feasible photoelectron transfer from bioactive π-expanded imidazole luminophores to ZnO nanocrystals. NEW J CHEM 2015. [DOI: 10.1039/c4nj02003k] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
Abstract
The chemical affinity between the nitrogen atom of the imidazole and the zinc ion on the surface of the nano oxide may be a reason for strong interaction of the ligand on nanoparticles causing the enhancement.
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Jayabharathi J, Karunakaran C, Kalaiarasi V, Ramanathan P. Nano ZnO, Cu-doped ZnO, and Ag-doped ZnO assisted generation of light from imidazole. J Photochem Photobiol A Chem 2014. [DOI: 10.1016/j.jphotochem.2014.09.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Spectroscopic Studies on Photoelectron Transfer from 2-(furan-2-yl)-1-phenyl-1H-phenanthro[9,10-d]imidazole to ZnO, Cu—doped ZnO and Ag—doped ZnO. J Fluoresc 2014; 24:1447-55. [DOI: 10.1007/s10895-014-1428-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Accepted: 07/07/2014] [Indexed: 10/24/2022]
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Jayabharathi J, Karunakaran C, Thanikachalam V, Ramanathan P. Binding and fluorescence enhancing behaviour of phenanthrimidazole with different phases of TiO2. NEW J CHEM 2014. [DOI: 10.1039/c4nj00610k] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Karunakaran C, Jayabharathi J, Kalaiarasi V, Jayamoorthy K. Enhancing photoluminescent behavior of 2-(naphthalen-1-yl)-1,4,5-triphenyl-1H-imidazole by ZnO and Bi2O3. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 118:182-186. [PMID: 24051287 DOI: 10.1016/j.saa.2013.08.098] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2013] [Revised: 08/14/2013] [Accepted: 08/23/2013] [Indexed: 06/02/2023]
Abstract
A fluorophore 2-(naphthalen-1-yl)-1,4,5-triphenyl-1H-imidazole [NTI] has been designed, synthesized and characterized by (1)H NMR, (13)C NMR, mass and single crystal XRD. Absorption, emission, lifetime and cyclic voltammetry have been made to deduce the interaction between NTI and ZnO and Bi2O3 nanocrystals. NTI act as a new host for ZnO and Bi2O3 nanocrystals that enhance its luminescence. The apparent binding constant has been obtained. Adsorption of the NTI on ZnO and Bi2O3 nanocrystals lowers the HOMO energy level of the NTI. The strong adsorption of the NTI on the surface of ZnO and Bi2O3 nanocrystals is likely due to the chemical affinity of the nitrogen atom of the NTI to the zinc ion on the surface of nanocrystals. SEM and EDS spectra confirmed the adsorption of NTI on the surface of nanocrystals.
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Affiliation(s)
- C Karunakaran
- Department of Chemistry, Annamalai University, Annamalainagar 608 002, Tamilnadu, India
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Effect of electron withdrawing anchoring groups on the optoelectronic properties of pyrene sensitizers and their interaction with TiO2: A combined experimental and theoretical approach. J Photochem Photobiol A Chem 2013. [DOI: 10.1016/j.jphotochem.2013.07.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Karunakaran C, Jayabharathi J, Sathishkumar R, Jayamoorthy K, Vimal K. Contrasting emission behaviour of phenanthroimidazole with ZnO nanoparticles. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 115:488-492. [PMID: 23871976 DOI: 10.1016/j.saa.2013.06.073] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 05/10/2013] [Accepted: 06/20/2013] [Indexed: 06/02/2023]
Abstract
A new fluorophore 2-(4-fluorophenyl)-1-phenyl-1H-phenanthro [9,10-d]imidazole has been synthesized and characterized by spectroscopic techniques. Nanoparticulate ZnO enhances the fluorescence of the synthesised fluorophore. The absorption, fluorescence, lifetime, cyclic voltammetry and infrared studies reveal that fluorophore is attached to the surface of ZnO semiconductor. Photo-induced electron transfer (PET) explains the enhancement of fluorescence by nanoparticulate ZnO and the apparent binding constant has been obtained. Adsorption of the fluorophore on ZnO nanoparticle lowers the HOMO and LUMO energy levels of the fluorophore. The strong adsorption of the phenanthrimidazole derivative on the surface of ZnO nanocrystals is likely due to the chemical affinity of the nitrogen atom of the organic molecule to the zinc ion on the surface of nanocrystal.
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Affiliation(s)
- C Karunakaran
- Department of Chemistry, Annamalai University, Annamalainagar 608 002, Tamil Nadu, India
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Karunakaran C, Jayabharathi J, Jayamoorthy K. Benzimidazole derivative vs. different phases of TiO2-physico-chemical approach. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 114:303-308. [PMID: 23778170 DOI: 10.1016/j.saa.2013.05.082] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 05/17/2013] [Accepted: 05/23/2013] [Indexed: 06/02/2023]
Abstract
1-Benzyl-2-phenyl-1H-benzo[d]imidazole (BPBI) has been synthesized by simple steps and characterized by spectral studies. Absorption and fluorescence spectral studies have been employed to investigate the interaction of BPBI with the anatase, hombikat, P25 and rutile phases of TiO2. The emission of the BPBI is efficiently quenched by anatase, hombikat and P25 TiO2 nanoparticles owing to charge injection from the excited singlet state of BPBI to the conduction band of the TiO2 nanoparticles. Surprisingly, rutile phase enhances the fluorescence which is likely due to lowering of LUMO and HOMO levels of the ligand on ducking of the benzimidazole moiety of the BPBI molecule into the void space of rutile TiO2. Electron injection from photoexcited BPBI to the TiO2 conduction band (S*→S(+)+e(-)(CB)) is likely to enhance the fluorescence.
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Affiliation(s)
- C Karunakaran
- Department of Chemistry, Annamalai University, Annamalainagar 608 002, Tamilnadu, India
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Karunakaran C, Jayabharathi J, Sathishkumar R, Jayamoorthy K. Interaction of fluorescent sensor with superparamagnetic iron oxide nanoparticles. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 110:151-156. [PMID: 23562745 DOI: 10.1016/j.saa.2013.03.042] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/02/2013] [Accepted: 03/04/2013] [Indexed: 06/02/2023]
Abstract
To sense superparamagnetic iron oxides (Fe2O3 and Fe3O4) nanocrystals a sensitive bioactive phenanthroimidazole based fluorescent molecule, 2-(4-fluorophenyl)-1-phenyl-1H-phenanthro [9,10-d] imidazole has been designed and synthesized. Electronic spectral studies show that phenanthroimidazole is bound to the surface of iron oxide semiconductors. Fluorescent enhancement has been explained on the basis of photo-induced electron transfer (PET) mechanism and apparent binding constants have been deduced. Binding of phenanthroimidazole with iron oxide nanoparticles lowers the HOMO and LUMO energy levels of phenanthroimidazole molecule. Chemical affinity between the nitrogen atom of the phenanthroimidazole and Fe(2+) and Fe(3+) ions on the surface of the nano-oxide may result in strong binding of the phenanthroimidazole derivative with the nanoparticles. The electron injection from the photoexcited phenanthroimidazole to the iron oxides conduction band explains the enhanced fluorescence.
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Karunakaran C, Jayabharathi J, Venkatesh Perumal M, Thanikachalam V, Kumar Thakur P. Electronic properties of phenanthrimidazoles as hole transport materials in organic light emitting devices and in photoelectron transfer to ZnO nanoparticles. J PHYS ORG CHEM 2013. [DOI: 10.1002/poc.3100] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | | | | | | | - Prasoon Kumar Thakur
- Division of Nematology; Indian Agricultural Research Institute; New Delhi-12; India
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Abstract
The photochemical behavior of xanthene dyes (fluorescein, erythrosine, and eosin) with colloidal SnO2nanoparticles was probed by UV-visible, steady state, and time resolved fluorescence measurements. The prepared SnO2nanoparticles were characterized by using UV-visible and powder XRD measurements. The xanthene dyes were adsorbed on the surface of colloidal SnO2nanoparticles through electrostatic interaction. Apparent association constant (Kapp) was calculated from the relevant fluorescence data. The larger value of apparent association constant indicates a strong association between xanthene dyes and SnO2nanoparticles. The fluorescence quenching is mainly attributed to electron transfer from the excited state xanthenes to the conduction band of colloidal SnO2. The electron transfer mechanism was explained based on the Rehm-Weller equation as well as the energy level diagram.
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Karunakaran C, Jayabharathi J, Jayamoorthy K, Vinayagamoorthy P. Photoinduced electron-transfer from benzimidazole to nanocrystals. J Mol Liq 2013. [DOI: 10.1016/j.molliq.2012.10.032] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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25
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Inhibition of fluorescence enhancement of benzimidazole derivative on doping ZnO with Cu and Ag. J Photochem Photobiol A Chem 2012. [DOI: 10.1016/j.jphotochem.2012.08.006] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Karunakaran C, Jayabharathi J, Jayamoorthy K, Devi KB. Photoinduced electron-transfer from imidazole derivative to nano-semiconductors. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2012; 89:187-193. [PMID: 22261106 DOI: 10.1016/j.saa.2011.12.065] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2011] [Revised: 11/24/2011] [Accepted: 12/21/2011] [Indexed: 05/31/2023]
Abstract
Bioactive imidazole derivative absorbs in the UV region at 305 nm. The interaction of imidazole derivative with nanoparticulate WO3, Fe2O3, Fe3O4, CuO, ZrO2 and Al2O3 has been studied by UV-visible absorption, FT-IR and fluorescence spectroscopies. The imidazole derivative adsorbs strongly on the surfaces of nanosemiconductor, the apparent binding constants for the association between nanomaterials and imidazole derivative have been determined from the fluorescence quenching. In the case of nanocrystalline insulator, fluorescence quenching through electron transfer from the excited state of the imidazole derivative to alumina is not possible. However, a possible mechanism for the quenching of fluorescence by the insulator is energy transfer, that is, energy transferred from the organic molecule to the alumina lattice. Based on Forster's non-radiation energy transfer theory, the distance between the imidazole derivative and nanoparticles (r0∼2.00 nm) as well as the critical energy transfer distance (R0∼1.70 nm) has been calculated. The interaction between the imidazole derivative and nanosurfaces occurs through static quenching mechanism. The free energy change (ΔGet) for electron transfer process has been calculated by applying Rehm-Weller equation.
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Affiliation(s)
- C Karunakaran
- Department of Chemistry, Annamalai University, Annamalainagar 608002, Tamilnadu, India
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Photosensitization of Imidazole Derivative by ZnO Nanoparticle. J Fluoresc 2012; 22:1047-53. [DOI: 10.1007/s10895-012-1042-4] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2011] [Accepted: 03/07/2012] [Indexed: 11/27/2022]
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Asha Jhonsi M, Kathiravan A, Paramaguru G, Manivannan C, Renganathan R. Fluorescence Quenching of Tris(2,2′-bipyridine)Ruthenium(II) Dichloride by Certain Organic Dyes. J SOLUTION CHEM 2010. [DOI: 10.1007/s10953-010-9594-x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Kathiravan A, Renganathan R. Fluorescence Quenching of Phycoerythrin by Anthraquinone Dyes. Z PHYS CHEM 2010. [DOI: 10.1524/zpch.2010.5518] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
Fluorescence quenching of phycoerythrin (PE) by a series of anthraquinone dyes has been investigated using steady state fluorescence technique in water medium. The dyes used were Uniblue, Acid blue 129, Alizarin and Alizarin red S. The quenching of PE was found to obey the Stern-Volmer equation and the corresponding Stern-Volmer plots were linear indicating the dynamic quenching. The quenching rate constants (k
q) were calculated by using fluorescence data. The mechanism of quenching is discussed on the basis of quenching rate constants as well as the reduction potential of dyes. The electron transfer mechanism has been proved by the calculation of free energy change (ΔGet) by applying Rehm-Weller equation.
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Jhonsi MA, Renganathan R. Investigations on the photoinduced interaction of water soluble thioglycolic acid (TGA) capped CdTe quantum dots with certain porphyrins. J Colloid Interface Sci 2010; 344:596-602. [PMID: 20132944 DOI: 10.1016/j.jcis.2010.01.022] [Citation(s) in RCA: 64] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2009] [Revised: 12/29/2009] [Accepted: 01/08/2010] [Indexed: 10/20/2022]
Abstract
The photoinduced interaction of TGA capped CdTe quantum dots (QDs) with porphyrins such as meso-tetrakis(4-sulfonatophenyl)porphyrin [TSPP], meso-tetrakis(4-carboxyphenyl)porphyrin [TCPP], meso-tetrakis (4-N-methylpyridyl)porphyrin [TMPyP] and meso-tetraphenylporphyrin [TPP] has been studied by using absorption, steady state and time resolved fluorescence spectroscopy. The QD surface was negatively charged due to thiol capping agent containing carboxylic group. Positively charged TMPyP interacts with QDs through charge transfer mechanism, negatively charged porphyrins (TCPP and TSPP) interacted through energy transfer mechanism and the neutral one (TPP) does not have any interaction. The Stern-Volmer constant, quenching rate constant, association constants, rate of electron transfer and energy transfer parameters were calculated from the fluorescence data. Effect of molecular structure has also been studied.
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Affiliation(s)
- M Asha Jhonsi
- School of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India
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31
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Kathiravan A, Jhonsi MA, Thiruvengadam J, Renganathan R. Photoinduced Electron Transfer between Triphenylpyrylium Ion (TPP+) and Certain Phenols. Z PHYS CHEM 2009. [DOI: 10.1524/zpch.2008.5418] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The photoinduced interaction between triphenylpyrylium ion (TPP+) and certain phenols were studied in acetonitrile medium by using absorption, steady state and time resolved fluorescence spectroscopic methods. The quenchers used were phenol, o-aminophenol, o-cresol, o-hydroxyphenol, o-chlorophenol, salicylic acid and salicylaldehyde. Linear Stern-Volmer plots were obtained from both steady state and time resolved measurements and also the calculated values of bimolecular quenching rate constants (k
q) were matched well. The free energy change (ΔG
et) has been evaluated by using Rehm-Weller equation for the confirmation of electron transfer from phenols to TPP+ ion.
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Kathiravan A, Anbazhagan V, Asha Jhonsi M, Renganathan R. A Study on the Fluorescence Quenching of Eosin by certain Organic Dyes. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.2008.5267] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The fluorescence quenching of Eosin by certain dyes has been investigated using steady state technique. The dyes used are Uniblue-A, Acid blue 129, Alizarin, Alizarin red S, Erichrome Black T, Tartrazine, Methyl orange, Methyl red, Acid orange 63, Congo red. The quenching was found to obey the Stern-Volmer equation and the corresponding Stern-Volmer plots were linear in the range of quencher concentration used [0−5×10−
5] M. The quenching rate constant (k
q
) is in the range of 0.85–26.65×1012 M−
1s−
1. The quenching mechanism is discussed on the basis of the quenching rate constants as well as the reduction potential of the dyes. Rehm-Weller equation is applied for the calculation of free energy change (ΔGet).
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Kathiravan A, Anbazhagan V, Jhonsi MA, Renganathan R. Fluorescence Quenching of Xanthene Dyes by TiO2. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.2007.221.7.941] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The fluorescence quenching of xanthene dyes by TiO2 has been investigated using steady state technique. The dyes used are eosin, rhodamine B, rhodamine 6G. The quenching was found to obey Stern-Volmer equation and the corresponding Stern-Volmer plots were linear in the range of quencher concentration used [0–5 × 10--5] M. The quenching rate constant (k
q) is in the range of 0.77–8.30 × 1012 M-1 s-1. This study reveals effective quenching of xanthene dyes with TiO2. The quenching of xanthene dyes followed electron transfer mechanism.
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Kathiravan A, Renganathan R. Fluorescence Quenching of Meso-Tetrakis(p-Sulfonatophenyl)Porphyrin (TSPP) by certain Organic Dyes. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.2008.5215] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
The fluorescence quenching of meso-tetrakis (p-sulfonatophenyl) porphyrin (TSPP) by certain anthraquinone and azo dyes has been investigated using steady state fluorescence technique. The dyes used were Uniblue-A, Acid blue 129, Alizarin, Alizarin red S, Erichrome Black T, Tartrazine, Methyl orange, Methyl red, Acid orange 63 and Congo red. The quenching was found to obey Stern-Volmer equation and the corresponding Stern-Volmer plots were linear. The quenching rate constant (k
q
) is in the order of 0.19–6.08×1012 M−
1s−
1. This study reveals effective quenching of TSPP by organic dyes.
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Jhonsi MA, Renganathan R. Photoinduced Electron Transfer from Meso-Tetrakis (N-methylpyridyl)porphyrin (TMPyP) to Colloidal CdS. ACTA ACUST UNITED AC 2009. [DOI: 10.1524/zpch.2008.5436] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Abstract
A stable colloidal CdS nanoparticles were prepared. The dynamics of photoinduced interaction between meso-tetrakis(N-methylpyridyl)porphyrin (TMPyP) and colloidal CdS were studied using absorption, steady state, time resolved fluorescence and FT-IR spectral measurements. The apparent association constant (K
app) of TMPyP-CdS obtained from absorption spectral changes is 1.07×103 M−1. The K
app value of TMPyP-CdS as determined from fluorescence spectra is 1.34×103 M−1, which matches well with that determined from the absorption spectra changes. These data indicate that there is an interaction between TMPyP and colloidal CdS nanoparticle surface. The dynamics of photoinduced electron transfer from TMPyP to the conduction band of colloidal CdS nanoparticle has been observed and the mechanism of electron transfer has been confirmed by the calculation of free energy change (ΔG
et) by applying Rehm-Weller equation as well as energy level diagram. Lifetime measurements gave the rate constant (k
et) for electron injection from the excited state TMPyP into the conduction band of CdS is 3.21×108 s–1.
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Kathiravan A, Renganathan R. Photosensitization of colloidal TiO2 nanoparticles with phycocyanin pigment. J Colloid Interface Sci 2009; 335:196-202. [DOI: 10.1016/j.jcis.2009.03.076] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2008] [Revised: 02/20/2009] [Accepted: 03/07/2009] [Indexed: 10/20/2022]
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37
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Kathiravan A, Chandramohan M, Renganathan R, Sekar S. Photoinduced electron transfer from phycoerythrin to colloidal metal semiconductor nanoparticles. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2009; 72:496-501. [PMID: 19083264 DOI: 10.1016/j.saa.2008.10.021] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2008] [Revised: 10/12/2008] [Accepted: 10/17/2008] [Indexed: 05/27/2023]
Abstract
Phycoerythrin is a water soluble pigment which absorbs in the visible region at 563 nm. The interaction of phycoerythrin with colloidal metal semiconductors was studied by absorption, FT-IR and fluorescence spectroscopy. Phycoerythrin adsorbed strongly on the surface of TiO(2) nanoparticles, the apparent association constant for the association between colloidal metal-TiO(2) nanoparticles and phycoerythrin was determined from fluorescence quenching data. The free energy change (DeltaG(et)) for electron transfer process has been calculated by applying Rehm-Weller equation.
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Affiliation(s)
- A Kathiravan
- School of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India
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Kathiravan A, Anbazhagan V, Asha Jhonsi M, Renganathan R. Interaction of meso-tetrakis (p-sulfonatophenyl) porphyrin (TSPP) with pyrimidines: A steady state and time-resolved fluorescence quenching study. J Mol Struct 2009. [DOI: 10.1016/j.molstruc.2008.08.013] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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39
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Photoinduced electron transfer reactions between meso-tetrakis(4-sulfonatophenyl)porphyrin and colloidal metal-semiconductor nanoparticles. Colloids Surf A Physicochem Eng Asp 2009. [DOI: 10.1016/j.colsurfa.2008.09.042] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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40
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Kathiravan A, Chandramohan M, Renganathan R, Sekar S. Cyanobacterial chlorophyll as a sensitizer for colloidal TiO2. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2009; 71:1783-1787. [PMID: 18678524 DOI: 10.1016/j.saa.2008.06.031] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2008] [Revised: 06/17/2008] [Accepted: 06/25/2008] [Indexed: 05/26/2023]
Abstract
Chlorophyll has been extracted from cyanobacteria. The adsorption of chlorophyll on the surface of colloidal TiO(2) through electrostatic interaction was observed. The apparent association constant (K(app)) of chlorophyll-TiO(2) obtained from absorption spectra is 3.78x10(4)M(-1). The K(app) value of chlorophyll-TiO(2) as determined from fluorescence spectra is 1.81x10(4)M(-1), which matches well with that determined from the absorption spectra changes. These data indicate that there is an interaction between chlorophyll and colloidal TiO(2) nanoparticle surface. The dynamics of photoinduced electron transfer from chlorophyll to the conduction band of colloidal TiO(2) nanoparticle has been observed and the mechanism of electron transfer has been confirmed by the calculation of free energy change (DeltaG(et)) by applying Rehm-Weller equation as well as energy level diagram. Lifetime measurements gave the rate constant (k(et)) for electron injection from the excited state chlorophyll into the conduction band of TiO(2) is 4.2x10(8)s(-1).
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Affiliation(s)
- A Kathiravan
- School of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India
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41
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Photoinduced electron transfer reactions of pyrylium derivatives with organic sulfides in acetonitrile. J Photochem Photobiol A Chem 2009. [DOI: 10.1016/j.jphotochem.2008.10.019] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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42
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Kathiravan A, Renganathan R. Effect of anchoring group on the photosensitization of colloidal TiO2 nanoparticles with porphyrins. J Colloid Interface Sci 2008; 331:401-7. [PMID: 19100559 DOI: 10.1016/j.jcis.2008.12.001] [Citation(s) in RCA: 99] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2008] [Revised: 11/07/2008] [Accepted: 12/01/2008] [Indexed: 10/21/2022]
Abstract
The interaction of porphyrins (TCPP, TSPP, TMeOPP and TPP) with colloidal TiO(2) nanoparticles was studied by infra-red, UV-visible absorption, steady state and time resolved fluorescence spectroscopy. The porphyrins (TCPP, TSPP and TMeOPP) adsorbed on the surface of colloidal TiO(2) nanoparticles through electrostatic interaction. According to absorption and fluorescence changes the apparent association constants (K(app)) were calculated. However, TPP did not interact with surface of colloidal TiO(2) nanoparticles due to the absence of anchoring group. The fluorescence quenching is attributable mainly to electron transfer from the excited state porphyrins to the conduction band of colloidal TiO(2). The rate of electron transfer process (k(et)) was calculated using lifetime measurement. The electron transfer mechanism has been proved by the calculation of free energy change (DeltaG(et)) by applying Rehm-Weller equation. Using all the spectroscopic measurements we confirmed that the presence of anchoring group plays major role in the adsorption as well as the electron transfer processes.
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Affiliation(s)
- A Kathiravan
- School of Chemistry, Bharathidasan University, Tiruchirappalli-620 024, Tamil Nadu, India
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43
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Kathiravan A, Renganathan R. An investigation on electron transfer quenching of zinc(II) meso-tetraphenylporphyrin (ZnTPP) by colloidal TiO(2). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 71:1106-1109. [PMID: 18424228 DOI: 10.1016/j.saa.2008.03.006] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/03/2007] [Revised: 03/03/2008] [Accepted: 03/03/2008] [Indexed: 05/26/2023]
Abstract
The interaction of zinc(II) meso-tetraphenylporphyrin (ZnTPP) with colloidal TiO(2) was studied by absorption, steady state and time-resolved fluorescence spectroscopy. The quenching was found to obey the Stern-Volmer equation and the corresponding Stern-Volmer plots were linear in the range of quencher concentration used 0-5 x 10(-4)M. The bimolecular quenching rate constants (k(q)) were 20.5 x 10(10)M(-1)s(-1) (steady-state) and 2.85 x 10(10)M(-1)s(-1) (time resolved). The quenching process is suggested to involve electron transfer from the ZnTPP to TiO(2) considering the experimental evidences obtained.
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Affiliation(s)
- A Kathiravan
- School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India
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44
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Kathiravan A, Renganathan R. Photoinduced interaction between riboflavin and TiO(2) colloid. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 71:1080-1083. [PMID: 18420452 DOI: 10.1016/j.saa.2008.03.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Accepted: 03/03/2008] [Indexed: 05/26/2023]
Abstract
The adsorption of riboflavin on the surface of TiO(2) colloidal particles and the electron transfer process from its singlet excited state to the conduction band of TiO(2) were examined by absorption and fluorescence quenching measurements. The apparent association constants (K(app)) were determined. The quenching mechanism is discussed involving electron transfer from riboflavin to TiO(2).
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Affiliation(s)
- A Kathiravan
- School of Chemistry, Bharathidasan University, Tiruchirappalli 620024, Tamil Nadu, India
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45
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Kathiravan A, Anbazhagan V, Asha Jhonsi M, Renganathan R. Fluorescence quenching of meso-tetrakis (4-sulfonatophenyl) porphyrin by colloidal TiO(2). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008; 70:615-8. [PMID: 17888718 DOI: 10.1016/j.saa.2007.08.007] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2007] [Revised: 08/07/2007] [Accepted: 08/13/2007] [Indexed: 05/17/2023]
Abstract
A stable colloidal TiO(2) has been prepared. The interaction of meso-tetrakis (4-sulfonatophenyl) porphyrin (TSPP) with colloidal TiO(2) was studied by absorption and fluorescence spectroscopy. Upon excitation of its absorption band, the fluorescence emission of TSPP was quenched by colloidal TiO(2). The bimolecular quenching rate constant (k(q)) is 1.78 x 10(11)M(-1)s(-1). The porphyrin can participate in the quenching process by injecting electrons from its excited states into the conduction band of TiO(2). The quenching mechanism is discussed on the basis of the quenching rate constant as well as the reduction potential of the colloidal TiO(2). Rehm-Weller equation was applied for the calculation of free energy change (DeltaG(et)).
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Affiliation(s)
- A Kathiravan
- School of Chemistry, Bharathidasan University, Tiruchirappalli 620 024, Tamil Nadu, India
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46
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Iijima Y, Obara S, Ohba Y, Kubo K, Sakurai T. 2,4,6-Triphenylpyrylium ion-mediated photooxidation of N,N-dibenzylhydroxylamine and its derivatives. J Photochem Photobiol A Chem 2001. [DOI: 10.1016/s1010-6030(01)00469-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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47
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Manoj N, Gopidas K. Photophysical and electron-transfer properties of a few 2,6-dimethyl-4-arylpyrylium derivatives. J Photochem Photobiol A Chem 1999. [DOI: 10.1016/s1010-6030(99)00135-5] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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48
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Jayanthi SS, Ramamurthy P. Excited Singlet State Reactions of Thiopyrylium with Electron Donors: Electron Transfer, Induction of Triplet by Internal and External Heavy Atom Effect, and Comparison of Pyrylium and Thiopyrylium Reactions. J Phys Chem A 1998. [DOI: 10.1021/jp9701101] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- S. S. Jayanthi
- Department of Inorganic Chemistry, School of Chemistry, University of Madras, Guindy Campus, Madras-600 025, India
| | - P. Ramamurthy
- Department of Inorganic Chemistry, School of Chemistry, University of Madras, Guindy Campus, Madras-600 025, India
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49
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Jayanthi SS, Ramamurthy P. Excited Singlet State Reactions of Triphenylpyrylium Ion with Electron Donors: Evidence for Electron Transfer and the Observation of Marcus Inverted Region for the Charge Shift in the Radical Pair. J Phys Chem A 1997. [DOI: 10.1021/jp9639408] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- S. S. Jayanthi
- Department of Inorganic Chemistry, School of Chemistry, University of Madras, Guindy Campus, Madras 600 025, India
| | - P. Ramamurthy
- Department of Inorganic Chemistry, School of Chemistry, University of Madras, Guindy Campus, Madras 600 025, India
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