الفهرس 
The concept of p????Only 14 pages are availabe for public view
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Abstract
Photophysical properties of some 1-naphthol and 2-naphthol sulfonate derivatives and their efficiency as singlet oxygen photosensitizers in aqueous media are reported. The fluorescence emission is mainly from the deproto-nated form (conjugate base) and their maxima cover the range of 433-529 nm. The fluorescence decay of these derivatives was found to be fitted with bi-exponential function with χ2 of about )1.0±0.1( in all cases. Rate constants for oxygen quenching of the excited singlet states of these compounds in H2O are found to be (1.2±0.2) × 1010 M-1s-1 for the neutral form and much lower for the quenching of their conjugate bases. p𝐾a values were found to be in the range )7.4 – 9.5 ( while p𝐾a∗ are close to zero and about 3.3 for 2-naphthol and 2-naphthol-6-sulfonate using Förster equation and in the range of )1.4-3.0( us-ing the fluorescence titration method obtained from the relative integrated flu-orescence intensity. Singlet oxygen quantum yields photosensitized by these photoacids were reported in D2O and found to be in the range )0.13 – 0.35( for the sulfonated derivatives.