Determination of the spectral dependences of the absolute quantum yields of O(1S) by the XeO* luminescence method. I. Photolysis of CO2and N2O

1979 ◽  
Vol 9 (7) ◽  
pp. 838-844 ◽  
Author(s):  
N K Bibinov ◽  
F I Vilesov ◽  
I P Vinogradov ◽  
L D Mikheev ◽  
A M Pravilov
Keyword(s):  
Quantum Yields ◽  
Luminescence Method ◽  
The Absolute ◽  
Absolute Quantum

Determination of the spectral dependences of the absolute quantum yields of XeF(B,C,D) excimers in photolysis of XeF2

1981 ◽  
Vol 11 (9) ◽  
pp. 1178-1181 ◽  
Author(s):  
N K Bibinov ◽  
I P Vinogradov ◽  
L D Mikheev ◽  
D B Stavrovskiĭ
Keyword(s):  
Quantum Yields ◽  
The Absolute ◽  
Absolute Quantum

Photooxidation effect of cupric complexes on aliphatic alcohols in nonaqueous solutions

1982 ◽  
Vol 47 (8) ◽  
pp. 2061-2068 ◽  
Author(s):  
Jan Sýkora ◽  
Mária Jakubcová ◽  
Zuzana Cvengrošová
Keyword(s):  
Coordination Sphere ◽  
Alcohol Oxidation ◽  
Aliphatic Alcohols ◽  
Oxidation Products ◽  
Molar Ratio ◽  
Quantum Yields ◽  
Nonaqueous Solutions ◽  
The Absolute ◽  
Absolute Quantum

In the photolysis of copper(II)-chloride-alcohol-acetonitrile systems (cCu = 1 mmol l-1, copper(II)-to-chloride molar ratio 1 : 2 to 1 : 8, 10% (v/v) alcohol), Cu(II) is reduced to Cu(I), and methanol, ethanol, 1-propanol, or 1-butanol is oxidized to the corresponding aldehyde, 2-propanol to acetone. In the case of 1-propanol and 1-butanol, chlorinated aldehydes are formed in addition too. The measured quantum yields of the photoreduction of Cu(II) to Cu(I) lay in the range of ΦCu(I) = 4.5 to 40 mmol einstein-1, the absolute quantum yields of the alcohol oxidation products were 2.3 to 47 mmol einstein-1. The photoactive components are chlorocupric complexes [CuClx](2-x)+ (x = 1-4). The presence of complexes with a higher number of chloroligands in the coordination sphere (x = 3, 4) brings about a decrease in the Cu(II) photoreduction rate. The decrease in the photoreduction rate observed in the presence of dioxygen is explained in terms of re-oxidation of copper(I) by the latter, resulting in an increase in the concentration of the photochemically active cupric complexes. The catalytic aspects of the systems in question are discussed with respect to this effect.

Absolute Quantum Yields for Exciplex Fluorescence

1990 ◽  
Vol 44 (1) ◽  
pp. 101-105 ◽  
Author(s):  
S. J. Hale ◽  
L. A. Melton
Keyword(s):  
Quantum Yield ◽  
Temperature Dependence ◽  
Room Temperature ◽  
Quantum Yields ◽  
Absolute Quantum Yield ◽  
The Absolute ◽  
Visualization Systems ◽  
Methyl Naphthalene ◽  
Absolute Quantum ◽  
Exciplex Fluorescence

The absolute quantum yields for exciplex fluorescence in four solutions which have potential as exciplex-based vapor/liquid visualization systems have been measured. The room-temperature absolute quantum yields for 10% dibutyl-aniline/0.4%, 1-cyanonaphthalene, 12.5% 1-methyl-naphthalene/0.5% N,N,N′,N′-tetramethyl- p-phenylenediamine (TMPD), 10% trihexylamine/1.0% 1-cyanonaphthalene, and 10% naphthalene/1.0% TMPD in hexadecane or cyclohexane are 0.03 ± 0.005, 0.05 ± 0.002 (308 nm), 0.02 ± 0.001, and 0.16 ± 0.021, respectively. The temperature dependence of the absolute quantum yield for the 10% naphthalene/1% TMPD in the hexadecane system was measured over the range of 23 to 260°C and was found to decrease by 20–30% at 260°C.

Novel Experimental Technique for the Absolute Determination of Quantum Yields

1998 ◽  
Vol 52 (8) ◽  
pp. 1103-1110
Author(s):  
G. Kaindl ◽  
R. Weger ◽  
P. Bajons
Keyword(s):  
Quantum Yield ◽  
Light Emission ◽  
Practical Method ◽  
New Method ◽  
Quantum Yields ◽  
Absolute Determination ◽  
Exciting Wavelength ◽  
Fluorescence Light ◽  
The Absolute

A new method for the absolute determination of the quantum yield based on the trapping of fluorescence light within a cylinder is discussed. First the trapping probability of photons—which are emitted in transparent rods or fluid-filled tubes—is investigated theoretically. The studies are based on the extension of light governed by the laws of reflection and refraction. The effect of nonhomogeneous distribution of the centers of fluorescence light emission on the calculation procedures is taken into account. Then the adaptation of the theoretical results to a new practical method is shown. The quantum yield as a function of the exciting wavelength is determined in one experimental cycle. The discussion of the method is performed by measurements on fluorescein in aqueous solution. The results are compared to literature data. The conformity demonstrates the applicability of the new method.

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