Oxygen lifetime

Pace, A. and Clennan, E.L. (2002). A new experimental protocol for intrazeolite photooxidations. The first product-based estimate of an upper limit for the intrazeolite singlet oxygen lifetime. J. Am. Chem. Soc. 124, 11236-11237... 

Jockusch, S., Sivaguru, J., Turro, N.J. and Ramamurthy, V. (2005). Direct measurement of the singlet oxygen lifetime in zeolites by near-IR phosphorescence. Photochem. Pho-tobiol. Sci. 4, 403-405... 

Lower Limit of Singlet Oxygen Lifetimes in Various Solvents (after ref. 124)... 

II. SINGLET-OXYGEN LIFETIMES IN THE ABSENCE OF ADDED QUENCHERS... 

Table 9 Singlet oxygen lifetimes in various solvents 887...

Merkel, P.B., Nilsson, R. and Kearns, D.R., 1972. Deuterium effects on singlet oxygen lifetimes in solutions. A new test of singlet oxygen reactions. J. Am. Chem. Soc., 94 1030—1031. 

III. INFLUENCE OF MODEL MEMBRANES ON SINGLET OXYGEN LIFETIMES... 

Solutions without Pc gave very weak luminescence at 7(X) nm, detected only when high fullerene concentrations and laser intensities were used. Addition of as little as 10 M Pc increased the intensity by an order of magnitude. Increasing the Pc concentration caused a further increase in intensity. The lifetime of the 700 nm luminescence was shorter than that at 1270 nm by a factor of 2 Fig. 1 shows the relationship in similar lifetime relationships occur in solvents with a wide range of singlet oxygen lifetimes and in the presence and absence of quenchers (Fig. 2). In all cases, the intensity at 700 nm was... 

The dissociation of ( 2)2 to 2 must be very fast, since the singlet oxygen lifetime is not affected by laser power (at least at the relatively low powers used in these experiments). If a significant amount of singlet oxygen were tied up as dimol, this should lead to saturation kinetics of the Pc luminescence as power increases at high Pc concentrations, which is not observed. 

Singlet oxygen lifetime in bulk polymer matrices of poly(4-methyl-l-pentene) is 18 2 ps [103]. 

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