Mechanism for triplet-state concentration quenching in xanthene dyes

1986 ◽  
Vol 44 (3) ◽  
pp. 232-235 ◽  
Author(s):  
K. T. Ermaganbetov ◽  
G. A. Ketsle ◽  
Z. M. Muldakhmetov ◽  
L. V. Chirkova
Keyword(s):  
Triplet State ◽  
Concentration Quenching ◽  
Xanthene Dyes ◽  
State Concentration

Triplet state quantum yields for some arom atic hydrocarbons and xanthene dyes in dilute solution

1967 ◽  
Vol 299 (1458) ◽  
pp. 348-353 ◽  
Keyword(s):  
Triplet State ◽  
State Formation ◽  
Heavy Atom ◽  
Quantum Yields ◽  
Triplet States ◽  
Dilute Solution ◽  
Perturbation Techniques ◽  
Excited Singlet ◽  
Xanthene Dyes ◽  
Extinction Coefficients

Quantum yields of triplet state formation and extinction coefficients of the triplet states have been determined by direct depletion methods for solutions of anthracene, phenanthrene, 1,2,5,6-dibenzanthracene, fluorescein, dibromofluorescein, eosin and erythrosin. The values obtained for the hydrocarbons are in reasonable agreement with those obtained by other workers using energy transfer and heavy atom perturbation techniques. In all cases which we have studied, the sum of the quantum yields of fluorescence and triplet state formation is equal to unity within the limits of experimental error, showing that radiationless transfer from the excited singlet to the ground state is negligible.

scholarly journals Solid state concentration quenching of organic fluorophores in PMMA

2015 ◽  
Vol 17 (2) ◽  
pp. 1435-1440 ◽  
Author(s):  
Adam P. Green ◽  
Alastair R. Buckley
Keyword(s):  
Solid State ◽  
Methyl Methacrylate ◽  
Rhodamine 6G ◽  
Concentration Quenching ◽  
Organic Fluorophores ◽  
Poly Methyl Methacrylate ◽  
Coumarin 102 ◽  
State Concentration ◽  
Quenching Phenomenon

In this study the concentration quenching phenomenon is explored for seven organic singlet emitters (Rhodamine 6G, Pyridine 2, Lumogen F Red 305, Perylene, Coumarin 102, DCM and DCJTB) in an inert host of poly(methyl methacrylate) (PMMA).

Phosphorescence and orbital nature of triplet state of xanthene dyes

1977 ◽  
Vol 26 (6) ◽  
pp. 735-739 ◽  
Author(s):  
N. I. Kunavin ◽  
R. N. Nurmukhametov ◽  
G. T. Khachaturova
Keyword(s):  
Triplet State ◽  
Xanthene Dyes ◽  
Orbital Nature

The kinetics and mechanism of the reaction of atomic oxygen with acetylene

1973 ◽  
Vol 335 (1603) ◽  
pp. 547-562 ◽  
Keyword(s):  
Triplet State ◽  
Rate Constant ◽  
Ground State ◽  
Excited Molecule ◽  
Secondary Process ◽  
Experimental Conditions ◽  
Electronically Excited ◽  
Stable Product ◽  
State Concentration ◽  
Oxygen Atoms

A photoionization mass spectrometer has been used to study the reaction of ground-state oxygen atoms with acetylene. The oxygen atoms were produced in the absence of molecular oxygen in a discharge-flow system with nitrogen as the principal carrier gas. Several of the free radicals and stable product molecules that were observed previously have been studied in more detail. Experiments with added gases have shown that the methylene radicals observed are probably in their ground, triplet state. The ratio of rate constants for the reactions of CH 2 with O 2 and O respectively was found to be approximately 1:10. The dependence of the C 3 H 3 radical concentration on the experimental conditions showed that C 3 H 3 was formed in a secondary reaction, probably involving an excited molecule or radical. The rate constant for the reaction of the HCCO radical with O 2 was measured as 2.2 ± 1.2х10 7 1 mol -1 s -1 . The product observed at mass 42 appears to be ground-state ketene formed in the primary step, perhaps via a triplet state. However, the possibility that the ketene might be formed in a secondary process cannot be dismissed. The rate constant for the reaction of ground-state oxygen atoms with ketene was measured, with a result significantly lower than a previous study. The diacetylene concentration showed a complex dependence on reaction conditions. Analysis of the approach of [C 4 H 2 ] to its steady-state concentration gave a rate constant for the reaction of oxygen atoms with diacetylene of 1.6 ± 0.5 х10 9 1 mol -1 s -1 . The relation of these results to previous studies is discussed briefly. It is suggested that a reaction of one or more of the energetic primary products, such as electronically excited CH 2 , HCCO or ketene, could be responsible for the chemiluminescence of CH, OH and CHO.

Sign in / Sign up

Export Citation Format

Share Document