Fluorescence enhancement monitoring of pyrromethene laser dyes using their complexation with Ag nanoparticles (Ag NPs) was studied. The size of the prepared Ag NPs was determined by transmission electron spectroscopy and UV/Vis absorption spectroscopy. Mie theory was also used to confirm the size of NPs theoretically. The effect of different nanoparticle concentrations on the optical properties of 1 × 10(-4) M PM dyes shows that 40%of Ag NPs concentration (40%C Ag NPs) in complex is the optimum concentration. Also, the effects of different concentrations of PM dyes in a complex was measured. Emission enhancement factors were calculated for all samples. Fluorescence enhancement efficiencies depended on the input pumping energy of a Nd-YAG laser (wavelength 532 nm and 8 ns pulse duration) were reported and showed the lowest energy (28 and 32 mJ) in the case of PM567 and PM597, respectively.

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Controlling photophysical properties is critical for the continued development of electroluminescent devices and luminescent materials. The preparation and study of novel molecules suitable as luminescent for the development of optoelectrical devices have recently received a lot of attention. Even though the as-triazine unit is a good building block for organic active substances, it is rarely used in this context. We created here novel bis-triazine derivative dyes in the far UV–Vis range by alkylation of triazine-thione derivatives with appropriate dibromo compounds. At the B3LYP/6-311**G(d,p) basis set, their optimal molecular structures were obtained. DFT technique confirmed that the new triazine derivatives are in noncoplanar with one of the two phenyl rings and the triazine plane rotating out by 102.09. Also, depending on the energy gap difference between HOMO and LUMO, some important parameters including chemical potential (π), electronegativity (χ), and chemical hardness (η) were calculated. The compounds may be readily polarized and have significant NLO characteristics, as seen by the tiny HOMO–LUMO energy gap. The calculated values for the polarizability (α) of the two new triazine derivatives have the range 6.09–10.75 × 10–24 (esu). The emission peaks seemed to move to the long-wavelength (redshift), with a rise in the fluorescence band, suggesting that the singlet excited state is more polar than the ground state. The influence of solvent polarity and the intermolecular charge transfer (ICT) processes are reflected in the photophysical properties of new fused triazine derivatives. These properties such as extinction coefficient, absorption and emission cross-sections, fluorescence quantum yield, fluorescence lifetime, oscillator strength, the dipole moment, radiative decay rate constant, the energy yield of fluorescence, and the attenuation length were assessed and discussed.

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This paper deals the optical and photophysical properties of dihydrophenanthro [9,10-e] [1,2,4] triazine fluorescent derivative dyes doped in Silicate based sol-gel, homo-poly methyl methacrylate (PMMA). Solid hosts effect on the optical and photophysical parameters such as molar absorptivity, cross sections of singlet-singlet electronic absorption and emission spectra, excited state lifetime, quantum yield of fluorescence.Also the dipole moment of electronic transition, the length of attenuation and Oscillator strength of electronic transition from So →S1 have been detected. The dyes with different pumping power were pumped by 3 rd harmonic Nd:YAG pulsed laser 8ns pulse duration, with a repetition rate at (10Hz). Good Photo stability of compound 1 and 2 were obtained that was decreased to 49%, 54% and 46%, 40% of the initial ASE of dyes in sol gel and PMMA respectively, after 55000 pumping pulses at (10 mJ/pulse). The dyes in sol-gel show improved Photo stability compared with those in organic polymeric matrices.

Optical and photophysical properties of 6-substituted-1,2,4-Triazine fluorescent derivative dye doped in silicate based sol–gel, homopolymer of methyl methacrylate (PMMA), and copolymer (MMA/diethylene glycol dimethacrylate) (DEGDMA) were investigated. The pores of different hosts and caging of the dye were found to effect on the parameters such as molar absorptivity, cross sections of singlet–singlet electronic absorption and emission spectra, excited state lifetime, quantum yield of fluorescence. The dipole moment of electronic transition, the length of attenuation and oscillator strength of electronic transition from So → S1 have been calculated. The dye was pumped with different powers using 3rd harmonic Nd: YAG laser of 355 nm and pulse duration 8 ns, with repetition rate 10 Hz. Good photo stability for dye was attained. After 55,000 pumping pulses of (10 mJ/pulse), the photo-stabilities were decreased to 53%, 48%, and 45% of the initial ASE of dye in sol gel, PMMA, and Co-polymer respectively. The dye in sol–gel matrix showed improvement of photo stability compared with those in organic polymeric matrices.

This paper deals the optical and photophysical properties of dihydrophenanthro [9,10-e] [1,2,4] triazine fluorescent derivative dyes doped in Silicate based sol–gel, homo-poly methyl methacrylate (PMMA). Solid hosts effect on the optical and photophysical parameters such as molar absorptivity, cross sections of singlet–singlet electronic absorption and emission spectra, excited state lifetime, quantum yield of fluorescence. Also the dipole moment of electronic transition, the length of attenuation and Oscillator strength of electronic transition from So →S1 have been detected. The dyes with different pumping power were pumped by 3rd harmonic Nd:YAG pulsed laser 8ns pulse duration, with a repetition rate at (10Hz). Good Photo stability of compound 1 and 2 were obtained that was decreased to 49%, 54% and 46%, 40% of the initial ASE of dyes in sol gel and PMMA respectively, after 55000 pumping pulses at (10 mJ/pulse). The dyes in sol-gel show improved Photo stability compared with those in organic polymeric matrices.