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Abstract
As the laser dyes are fluorescent organic compounds which it can be tuned over a broad range of wavelengths from near infrared to ultraviolet so there is a lot of researches describe the synthesis of dyes, including our search. In this study we prepared two new laser dyes [2-(6-Hydroxy-3-oxo-3H-xanthen-9-yl)- N-(2-(6-hydroxy-3-oxo-3H-xanthen-9-yl)benzoyl)-N-(2-hydroxyphenyl)benzamide (o- OHAnF) and 2-(6-Hydroxy-3-oxo-3H-xanthen-9-yl)-N-(2-(6-hydroxy-3-oxo-3H-xanthen-9- yl)benzoyl)-N-(4-hydroxyphenyl)benzamide (p-OHAnF)] via chemical reaction in which the fluorescein dye used as a reactant material and confirmed their chemical structures by elemental analysis, 1H NMR, FTIR and mass spectroscopic techniques. As the dyes [(o-OHAnF) (p-OHAnF)] are new so it was important to study their behavior in different solvents. Different samples with different concentrations ranged from 1x10-4 mol/L to 8x10-7 mol/L of the three dyes were prepared. Optical properties such as absorption spectra, emission spectra and fluorescence lifetime of all samples were measured. Also some important photo physical parameters such as extinction coefficient (f), the absorption (va) and the emission (ve) cross-sections, fluorescence quantum yield (фf), oscillator strength( f), the dipole moment (o), radiative decay rate constant (kr), energy yield of fluorescence (Ef) and the attenuation length (n) were determined by using the absorption and emission spectra