الفهرس 
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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 (ε), the absorption (ζa) and the emission (ζe) cross-sections, fluorescence quantum yield (фf) , oscillator strength( f), the dipole moment (μ), radiative decay rate constant (kr), energy yield of fluorescence (Ef) and the attenuation length Λ(λ) were determined by using the absorption and emission spectra. Laser Induced Fluorescence (LIF) setup was built in using a blue diode laser (λ=450 nm) as pumping energy ranged from100 mW to 410 mW. It noticed that, the concentration of (1x10-4) M was the optimum concentration for fluorescein dye unlike to the new dyes which their optimum were 3x10-5M where all samples with different highest LIF efficiency. The photostabilities of the three laser dyes were carried out by pumping the samples transversely with blue diode laser (λ= 450 nm) with a power of 300 mw .The output energy was studied as a function of time. It was noticed from the resulting data that every dye had its own behavior which differ from the behavior of the other dyes. pH of the solution is found to have a very large effect on the absorption and emission spectra of the fluorescein and the new laser dye that was shown by curves of absorption and emission after adding drops of HCl or NaOH to the dyes in ethanol. It was noticed that the emission of the dyes and fluorescein in base medium is higher than the emission of the dye in acidic and neutral medium. The nature of the polar solvent which was polar protic or aprotic has an effect on the emission of the dye. In this work we choose six solvents; three protic (methanol, ethanol and ethylene glycol) and the other are aprotic (dimethyl formamide, tetrahydro furan and acetone) then their effect in the absorption and emission of the dyes were studied which gave high fluorescence in the protic solvent than in the aprotic solvent.