A theoretical study of thionine: spin–orbit coupling and intersystem crossing

dc.creatorRodriguez-Serrano, Angela
dc.creatorRai-Constapel, Vidisha
dc.creatorDaza, Martha C.
dc.creatorDoer, Markus
dc.creatorMarian, Christel M.
dc.date.accessioned2020-02-18T14:34:50Z
dc.date.accessioned2022-09-28T15:09:06Z
dc.date.available2020-02-18T14:34:50Z
dc.date.available2022-09-28T15:09:06Z
dc.date.created2020-02-18T14:34:50Z
dc.date.issued2012-12-01
dc.identifierhttp://hdl.handle.net/11634/21757
dc.identifierhttps://doi.org/10.1039/c2pp25224d
dc.identifier.urihttp://repositorioslatinoamericanos.uchile.cl/handle/2250/3670109
dc.description.abstractA study of the possible intersystem crossing (ISC) mechanisms (S ⇝ T) in thionine (3,7-diamino-phenothiazin-5-ium), which is conducive to the efficient population of the triplet manifold, is presented. The radiationless deactivation channels {S1,S2(π → π*) ⇝ T1,T2(π → π*)} have been examined. Since the direct ISC does not explain the high triplet quantum yield in this system, attention has been centered on the vibronic spin–orbit coupling between the low-lying singlet and triplet (π → π*) states of interest. An efficient population transfer from the S1(πH → πL*) state to the T2(πH−1 → πL*) state via this channel is confirmed. The calculated ISC rate constant for this channel is kISC ≈ 3.35 × 108 s−1, which can compete with the radiative depopulation of the S1(πH → πL*) state via fluorescence (kF ≈ 1.66 × 108 s−1) in a vacuum. The S1(πH → πL*) ⇝ T1(πH → πL*) and {S2(πH−1 → πL*) ⇝ T1,T2(π → π*)} ISC channels have been estimated to be less efficient (kISC ≈ 105–106 s−1). Based on the computed ISC rate constants and excited-state solvent shifts, it is suggested that the efficient triplet quantum yield of thionine in water is primarily due to the S1(πH → πL*) ⇝ T2(πH−1 → πL*) channel with a computed rate constant of the order of 108–109 s−1 which is in accord with the experimental finding (kISC = 2.8 × 109 s−1).
dc.relationK. M. Gangotri and R. C. Meena, Use of reductant and photosensitizer in photogalvanic cells for solar energy conversion and storage: oxalic acid– methylene blue system, J. Photochem. Photobiol., 2001, 141–175.
dc.relationC. Lal, Use of mixed dyes in a photogalvanic cell for solar energy conversion and storage: EDTA–thionine–azur-B system, J. Power Sources, 2004, 164, 926.
dc.relationF. Harris, Z. Sayed, S. Hussain and D. A. Phoenix, An investigation into potential of phenothiazinium-based photo-sensitisers to act as PDT agents, Photodiagn. Photodyn. Ther., 2004, 1, 231.
dc.relationJ. P. Tardivo, A. Del Giglio, C. Santos de Oliveira, D. Santesso Gabrielli, H. Couto Junqueira, D. Batista Tadab, D. Severino, R. de Fatima Turchiello and M. S. Baptista, Methylene blue in photodynamic therapy: from basic mechanisms to clinical applications, Photodiagn. Photodyn. Ther., 2005, 2, 175.
dc.relationE. M. Tuite and J. M. Kelly, Photochemical reactions of methylene blue and analogues with DNA and other biological substrates, J. Photochem. Photobiol., B, 1993, 21, 103.
dc.relationH. E. A. Kramer and A. Maute, Sensitized photooxygenation according to type I mechanism (radical mechanism) – part I. Flash photolysis experiments, Photochem. Photobiol., 1972, 15, 7.
dc.relationD. R. Kearns, Physical and chemical properties of singlet molecular oxygen, Chem. Rev., 1971, 71, 395.
dc.relationA. Rodriguez-Serrano, M. C. Daza, M. Doerr and C. M. Marian, A quantum chemical investigation of the electronic structure of thionine, Photochem. Photobiol. Sci., 2012, 11, 397.
dc.relationF. Furche and R. Ahlrichs, Adiabatic time-dependent density functional methods for excited state properties, J. Chem. Phys., 2002, 117, 7433.
dc.relationS. Grimme and M. Waletzke, A combination of Kohn–Sham density functional theory and multi-reference configuration interaction methods, J. Chem. Phys., 1999, 111, 5645.
dc.relationL. F. Epstein, F. Karush and E. Rabinowitch, A spectrophotometric study of thionine, J. Opt. Soc. Am., 1941, 31, 77.
dc.relationM. Nemoto, H. Kokubun and M. Koizumi, Determination of S*–T transition probabilities of some xantene and thiazine dyes on the basis of T-energy transfer. II. Results in the aqueous solution, Bull. Chem. Soc. Jpn, 1969, 42(1223), 2464.
dc.relationM. G. Neumann and M. J. Tiera, The use of basic dyes as photochemical probes, Química Nova, 1993, 16(4), 280.
dc.relationS. Das and P. V. Kamat, Can H-aggregates serve as light-harvesting antennae? Triplet–triplet energy transfer between excited aggregates and monomer thionine in aersol-OT solutions, J. Phys. Chem. B, 1999, 103, 209.
dc.relationE. Rabinowitch and L. F. Epstein, Polymerization of dyestuffs in solution. Thionine and methylene blue, J. Am. Chem. Soc., 1941, 63, 69.
dc.relationG. R. Haugen and E. R. Hardwick, Ionic association in aqueous solutions of thionine, J. Phys. Chem., 1963, 67, 725.
dc.relationG. R. Haugen and E. R. Hardwick, Ionic association in solutions of thionine. II. Fluorescence and solvent effects, J. Phys. Chem., 1965, 69, 2988.
dc.relationM. D. Archer, M. I. C. Ferreira, G. Porter and C. J. Tredwell, Picosecond study of Stern–Volmer quenching of thionine by ferrous ions, Nouv. J. Chim., 1977, 1, 9.
dc.relationU. Steiner, G. Winter and H. E. A. Kramer, Investigation of physical triplet quenching by electron donors, J. Phys. Chem., 1977, 81, 1104.
dc.relationS. K. Lower and M. A. El-Sayed, The triplet state and molecular electronic processes in organic molecules, Chem. Rev., 1966, 66, 199.
dc.rightshttp://creativecommons.org/licenses/by-nc-sa/2.5/co/
dc.rightsAtribución-NoComercial-CompartirIgual 2.5 Colombia
dc.titleA theoretical study of thionine: spin–orbit coupling and intersystem crossing
dc.typeGeneración de Nuevo Conocimiento: Artículos publicados en revistas especializadas - Electrónicos


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