Singlet and Triplet State Properties and Singlet Oxygen Yield of an Amino-Acyl-Quinoxalinone Yellow Dye

2021 ◽  
Author(s):  
Souad A. Mousa ◽  
Peter Douglas ◽  
Hugh D. Burrows ◽  
Bice S. Martincigh
Keyword(s):  
Triplet State ◽  
Singlet Oxygen ◽  
Oxygen Yield

scholarly journals Charge-transfer heptamethine dyes for NIR singlet oxygen generation

2019 ◽  
Vol 55 (38) ◽  
pp. 5511-5514 ◽  
Author(s):  
John B. Jarman ◽  
Dennis A. Dougherty
Keyword(s):  
Charge Transfer ◽  
Triplet State ◽  
Singlet Oxygen ◽  
State Formation ◽  
Charge Transfer State ◽  
Previous Evidence ◽  
Oxygen Generation ◽  
Singlet Oxygen Generation ◽  
A Charge ◽  
Transfer State

A heptamethine-based charge-transfer dye was designed based on previous evidence of triplet state formation in orthogonal charge-transfer partners and calculations suggesting the formation of a charge-transfer state in heptamethine dye derivatives.

Dye-triplet-state and singlet-oxygen quenching effects in solid state dye lasers

2000 ◽  
Author(s):  
Terence A. King ◽  
Mohammad Ahmad ◽  
Anthony Gorman ◽  
I. Hamblett ◽  
Mark D. Rahn
Keyword(s):  
Solid State ◽  
Triplet State ◽  
Singlet Oxygen ◽  
Dye Lasers ◽  
Oxygen Quenching ◽  
Singlet Oxygen Quenching

scholarly journals Photoacoustic Measurements of Porphyrin Triplet-State Quantum Yields and Singlet-Oxygen Efficiencies

1998 ◽  
Vol 4 (11) ◽  
pp. 2299-2307 ◽  
Author(s):  
Marta Pineiro ◽  
Ana L. Carvalho ◽  
Mariette M. Pereira ◽  
A. M. d'A. Rocha Gonsalves ◽  
Luís G. Arnaut ◽  
...  
Keyword(s):  
Triplet State ◽  
Singlet Oxygen ◽  
Quantum Yields

Molecular Basis of the Vulnerability of Photosystem II to Damage by Light

1995 ◽  
Vol 22 (2) ◽  
pp. 201 ◽  
Author(s):  
J Barber
Keyword(s):  
Triplet State ◽  
Singlet Oxygen ◽  
D1 Protein ◽  
Primary Electron ◽  
In Vivo Studies ◽  
Cytochrome B559 ◽  
Acceptor Side ◽  
Donor And Acceptor ◽  
Primary Cleavage

Using isolated reaction centres and cores of photosystem I1 (PSII) it has been possible to elucidate the details of two separate pathways which lead to photoinhibition. The acceptor side pathway involves charge recombination resulting in the formation of the triplet state of the primary electron donor, P680. This triplet state is harmless in the absence of oxygen but in its presence gives rise to highly reactive singlet oxygen. We have shown that this singlet oxygen specifically attacks the chlorophyll of P680 itself. This process, plus other possibilities, gives rise to degradation of Dl protein involving a primary cleavage in the stromal loop joining putative transmembrane regions four and five, to yield 23 kDa N-terminal and 10 kDa C-terminal fragments. In contrast a donor side pathway is oxygen independent and is due to detrimental secondary oxidations brought about by P680+. Oxidation of accessory chlorophyll (C670) and β-carotene are observed and D1 protein is degraded by a primary cleavage in the lumenal loop between the putative transmembrane segments one and two to yield 24 kDa C-terminal and 9 kDa N-terminal fragments. In vivo studies indicate that the acceptor pathway is more common. The reason for the inherent vulnerability of PSII to photoinduced damage is discussed in terms of the special nature of P68O and the implications of the role of cytochrome b559 as a versatile protectant against donor and acceptor side photoinactivation is also considered. The likely dimeric organisation of PSII in vivo adds an additional factor to the general discussion of the molecular processes which underlie the vulnerability of PSII to photoinduced damage.

Effects of NaCl upon TPPS4 triplet state characteristics and singlet oxygen formation

2007 ◽  
Vol 186 (2-3) ◽  
pp. 187-193 ◽  
Author(s):  
Lucimara P.F. Aggarwal ◽  
Mauricio S. Baptista ◽  
Iouri E. Borissevitch
Keyword(s):  
Triplet State ◽  
Singlet Oxygen ◽  
Oxygen Formation ◽  
Singlet Oxygen Formation

Synthesis, photophysicochemical properties and TD-DFT calculations of tetrakis(2-benzoyl-4-chlorophenoxy) phthalocyanines

2014 ◽  
Vol 18 (04) ◽  
pp. 326-335 ◽  
Author(s):  
Yusuf Yılmaz ◽  
John Mack ◽  
M. Kasım Şener ◽  
Mehmet Sönmez ◽  
Tebello Nyokong
Keyword(s):  
Quantum Yield ◽  
Dft Calculations ◽  
Triplet State ◽  
Singlet Oxygen ◽  
Quantum Yields ◽  
Visible Absorption ◽  
H Nmr ◽  
Wide Range ◽  
Td Dft ◽  
The Impact

The synthesis of metal free, magnesium and zinc tetrakis(2-benzoyl-4-chlorophenoxy) phthalocyanine derivatives (2–4) is described along with their characterization by elemental analysis, IR, UV-visible absorption, and 1 H NMR spectroscopy and mass spectrometry. Trends observed in the fluorescence, triplet state, singlet oxygen and photodegradation quantum yields and the triplet state lifetimes are also analyzed. The compounds exhibit high solubility in a wide range of organic solvents and no evidence of aggregation was observed over a wide concentration range. The Zn ( II ) complex (4) was found to have a very high singlet oxygen quantum yield (ΦΔ = 0.78) in dimethylsulfoxide (DMSO) and a reasonably large triplet state quantum yield (ΦT = 0.82). The photophysical and photochemical properties clearly demonstrate that these compounds could prove useful in singlet oxygen applications such as photodynamic therapy (PDT). DFT and TD-DFT calculations were used to assess the impact of the positional isomerism of the 2-benzoyl-4-chlorophenoxy substituents on the electronic structures and optical spectroscopy.

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