الفهرس 
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Abstract
Abstract In this thesis, I studied the interaction between some diolefinic laser dyes such as (E, E)-2, 5-bis [2-(4-(dimethylamino)phenyl) ethenyl]pyrazine (BDPEP), (E, E)-2, 5-bis [2-(1-methyl-1H-pyrrole-2-yl]pyrazine (BMPP) and (E, E)-2, 5-bis (3, 4-dimethoxystyryl) pyrazine (BDP) and some quinoline derivatives laser dyes. The applied quinoline derivatives laser dyes were 15, 15-difluoro-[1, 3, 2]diaazaborininodiquinoline (DDP), 15, 15-difluoro-[1, 3, 2] diaazaborininodiquinoline acetonitrile (DDPA) and 15, 15-difluoro-[1, 3, 2] diaazaborininodiquinoxaline acetonitrile (DDPOA). The study was performed in restricted media such as sol-gel and copolymer matrices. The photophysical properties such as singlet absorption, molar absorptivity, fluorescence spectra, dipole moment, fluorescence quantum yield, fluorescence lifetime and laser activity of some laser dyes have been measured in different restricted hosts and different free solvents. The absorption / fluorescence properties of these laser dyes in sol-gel glass matrices are compared with its respective properties in copolymer host and free solvents. Lasing range, photostability and gain coefficient of these laser dyes containing sol-gel glass and copolymer of methyl methacrylate (MMA) and hydroxyl ethylmethacrylate (HEMA samples are measured using diode laser pumping (450 nm). The E1/2 values as the energy necessary to reduce the dye laser intensity to 50% of the original value were measured. The gel laser materials show improved photostability with respect to comparable polymeric host materials. Upon using time dependent density function theory (TDDFT) method, the absorption and emission spectra of these laser molecules in sol-gel matrices are illustrated and compared to experimental results. Also, the effect of cadmium sulfide (CdS) quantum dots (QDs) on fluorescence intensities of the (E, E)-2, 5-bis [2-(4-(dimethylamino)phenyl) ethenyl]pyrazine (BDPEP), ), (E, E)-2, 5-bis [2-(1-methyl-1H-pyrrole-2-yl]pyrazine (BMPP) and (E, E)-2, 5-bis (3, 4-dimethoxystyryl) pyrazine (BDP) in sol-gel host was investigated. The effect of sol-gel matrix on HOMO-LUMO energy gap (Eg) and dipole moment (μ) of the BDPEP molecule are also investigated using M06-2X density function. A synthesis of a series of bis(5,6-diphenyl-1,2,4-triazines) via alkylation of 5,6-diphenyl-1,2,4-triazine-3(4H)-thione with the appropriate bis(halo) compounds in ethanolic KOH was reported. The chemical structures of these compounds were confirmed by spectroscopic techniques. The absorption and excited states emission spectra of a series of bis(5,6-diphenyl-1,2,4-triazines) were monitored experimentally in ethanol solvent. The molecular structures of these triazines were optimized using B3LYP/6-31G(d) level of theory. The electronic absorption and emission spectra of these compounds, in gas and ethanol solvent, were calculated using time dependent density functional theory (TDDFT) at mPW1PW91/ 6-31G (d) level.